bluuebunny/crossref_metadata_2025 huggingface dataset:
Primary malignant gonadal mesotheliomas and asbestos
Authors: Attanoos R L , Gibbs A R
Published: March 2003

Aims: 

The clinicopathological, immunohistochemical and aetiological aspects, with respect to asbestos, of seven primary gonadal mesotheliomas (three intratesticular, four ovarian) are described and compared. These tumours are extremely rare, poorly described and the knowledge of their natural history is very limited.

Methods and results: 

The cases were collated from the UK Health and Safety Executive Mesothelioma Register over a 24‐year period (1968–91). Primary mesotheliomas of the tunica vaginalis and ovary comprised 0.09% (10 cases) and 0.03% (three cases) of mesothelioma deaths, respectively. No primary intratesticular (non‐tunica vaginalis) malignant mesotheliomas have been described. In this study, we present seven (three intratesticular, four ovarian) primary malignant gonadal mesotheliomas. In both genders the tumours show a similar age distribution (with median onset in the sixth decade), a similar association with asbestos (in approximately 50% cases), a diverse histological spectrum (with predominantly tubulopapillary epithelial subtype tumours) and an immunophenotype that is comparable with malignant pleural and peritoneal mesothelioma. The clinical course appears variable (mean, 26 months; range, 9–50 months). All tumours in the study presented as localized masses and their prognosis appeared more favourable than that of diffuse pleural and peritoneal cases.

Conclusions: 

An awareness of the existence of these rare forms of malignant mesothelioma is important to prevent misdiagnosis. Immunohistochemistry has an important role in confirmation of the diagnosis. The accurate diagnosis of primary gonadal mesothelioma has potentially important medicolegal compensation considerations as a significant proportion of these cases are associated with asbestos.
Intercalated duct hyperplasia: possible relationship to epithelial‐myoepithelial carcinoma and hybrid tumours of salivary gland
Authors: Chetty R
Published: March 2003

Aims

: The aims of this study were to ascertain the incidence of intercalated duct hyperplasia in association with cases of epithelial‐myoepithelial carcinoma (EMC), and to explore a possible relationship between them and hybrid carcinomas of salivary glands.

Methods and results

: Seven cases of EMC with sufficient surrounding non‐tumour parotid were examined. Three cases contained foci of intercalated duct hyperplasia adjacent to the tumour. One of the cases was a hybrid tumour composed of EMC and mucoepidermoid carcinoma. The hyperplastic intercalated ducts formed multiple foci within the salivary parenchyma and were composed of bland, uniform ducts. Cytological atypia was not identified.

Conclusions

: Intercalated duct hyperplasia may be a precursor lesion to EMC. Furthermore, it may also explain why EMC is frequently associated with other salivary gland carcinomas, so‐called hybrid tumours, as well as sharing histological features with adenoid cystic carcinoma. Recognition of the latter is of particular importance because adenoid cystic carcinoma carries a poor prognosis.
Polymerase chain reaction in the diagnosis of T‐cell lymphoma in paraffin‐embedded bone marrow biopsies: a comparative study
Authors: Gebhard S , Benhattar J , Bricod C , Meugé‐Moraw C , Delacrétaz F
Published: March 2003

In routine histological analysis of bone marrow biopsies, the distinction between reactive T‐cell infiltrates and T‐cell lymphoma can be difficult, even with the use of extensive immunohistochemistry. The aim of this study was to evaluate the diagnostic contribution of TCR‐γ gene rearrangement analysed by PCR.

The samples studied consisted of 46 paraffin‐embedded bone marrow biopsies (diagnosis, staging and follow‐up) from 26 patients with T‐cell lymphoma. The bone marrow biopsies were categorized into three groups according to the morphological and immunohistochemical results. Group 1, positive for T‐cell lymphoma (24 bone marrow biopsies), group 2, suspicion of T‐cell lymphoma (15 bone marrow biopsies) and group 3, negative for T‐cell lymphoma (seven bone marrow biopsies). DNA could be amplified in 45/46 bone marrow biopsies (98%). Clonal rearrangement was detected in 30/45 bone marrow biopsies tested (67%) including 15/24 bone marrow biopsies (62.5%) of group 1, 11/14 (78.5%) of group 2 and 4/7 (57%) of group 3. In total, PCR analysis supported a diagnosis of T‐cell lymphoma in 15/45 bone marrow biopsies (33%), in which histological and/or immunohistochemical examination provided inconclusive evidence of malignancy.

TCR‐γ PCR is a complementary tool for the assessment of T‐cell lymphoma in bone marrow biopsies. Optimal evaluation of bone marrow biopsies requires an integrative approach of all available results from morphology, immunohistochemistry, molecular biology and clinical data.
Apoptotic activity in gestational trophoblastic disease correlates with clinical outcome: assessment by the caspase‐related M30 CytoDeath antibody
Authors: Chiu P M , Ngan Y S , Khoo U S , Cheung A N Y
Published: March 2003

The objective of this study was to assess apoptotic activity in gestational trophoblastic disease (GTD) and its prognostic value in hydatidiform mole (HM).

Expression of the specific caspase cleavage site within cytokeratin 18 was assessed immunohistochemically using the monoclonal antibody M30 CytoDeath in 12 spontaneous abortions, 22 partial and 57 complete HM, eight choriocarcinoma (CCA) and 28 normal placentas. The M30 immunoreactivity occurred predominantly in the syncytiotrophoblasts. A significantly higher M30 index in HM and CCA was found when compared with normal placentas and spontaneous abortions (P < 0.001). The M30 index of those HM which spontaneously regressed was significantly higher than those HM which developed persistent disease requiring chemotherapy (P < 0.001). The M30 index correlated with another apoptotic index previously detected by TdT‐mediated dUTP nick‐end labelling (TUNEL) (P = 0.007) and the proliferation index assessed by the Ki67 antigen (P = 0.034).

We conclude that apoptosis is important in the pathogenesis of GTD. Assessment of apoptotic activity in HM by the M30 index may be considered as an alternative prognostic indicator for predicting the clinical behaviour.
Monoclonal antibody SM047 as an immunohistochemical marker of ovarian adenocarcinoma
Authors: McCluggage W G , Maxwell P , Veenstra H , Fick C E , Laeng R H , Tiltman A J
Published: March 2003

Monoclonal antibody SM047 as an immunohistochemical marker of ovarian adenocarcinoma

Aims: This study describes the generation of a monoclonal antibody designated SM047 which binds to an epitope that is displayed by a multivalent antigen associated with the glycocalyx of ovarian adenocarcinoma cells. The study also investigates SM047 staining in adenocarcinomas of diverse sites in order to determine whether the antibody is specific for ovarian adenocarcinoma and of value in the confirmation of an ovarian origin when the site of primary tumour is unknown.

Methods and results: SM047, an IgM monoclonal antibody, was the product of hybridoma cells derived from fusion of SP2 myeloma cells with splenocytes of a mouse that had been immunized with a membrane preparation of tumour (ovarian serous cystadenocarcinoma) and boosted with cells from a cell line established from a similar tumour in a different patient. Sixty‐two primary ovarian adenocarcinomas (28 serous, 23 mucinous, five endometrioid and six clear cell), 69 adenocarcinomas arising primary at other sites and 10 mesotheliomas were stained with SM047. There was positive membrane staining, which was usually strong and widespread, in 27 of 28 ovarian serous carcinomas and in all ovarian endometrioid and clear cell carcinomas. Most ovarian mucinous tumours were negative or exhibited weak cytoplasmic staining. Staining was variable in the other tumours but there was positive staining of most endometrial, endocervical and pancreatic adenocarcinomas. Most colonic adenocarcinomas were negative or exhibited weak cytoplasmic staining.

Conclusions: SM047 is strongly expressed in most ovarian serous adenocarcinomas and in other female genital tract adenocarcinomas, with the exception of ovarian mucinous tumours. The antibody may be useful in confirming the ovarian origin of an adenocarcinoma when used as part of a larger panel. This is especially so in the distinction between a non‐mucinous ovarian adenocarcinoma, which usually exhibits strong membranous staining, and a colonic adenocarcinoma which is usually negative or exhibits weak cytoplasmic staining. These findings need to be confirmed by further study of larger numbers of cases.
Tryptase‐positive mast cells accompany lymphocytic as well as lymphoplasmacytic lymphoma infiltrates in bone marrow trephine biopsies
Authors: Wilkins B S , Buchan S L , Webster J , Jones D B
Published: March 2003

Tryptase‐positive mast cells accompany lymphocytic as well as lymphoplasmacytic lymphoma infiltrates in bone marrow trephine biopsies

Aims: To investigate the specificity of increased bone marrow mast cell numbers in lymphoplasmacytic lymphoma (LPL) and to evaluate the relationship between mast cell number and the immunoglobulin phenotype of neoplastic lymphoid cells.

Methods and results: Retrospective study of bone marrow trephine biopsy specimens from patients with LPL, compared with selected cases representing chronic lymphocytic leukaemia (CLL) and multiple myeloma (MM) of known immunoglobulin light and heavy chain phenotype. Bone marrow mast cells were counted following immunohistochemical staining of sections for mast cell tryptase. We have confirmed previous observations that mast cell numbers are increased in bone marrow infiltrates of LPL. However, we found similarly high mast cell numbers in CLL. High mast cell numbers were associated with neoplastic lymphoid cells expressing an IgM κ phenotype. Mast cell numbers were low in all cases of MM studied and in controls with no lymphoma present. We observed an apparent bias towards κ light chain expression in our cases of LPL.

Conclusions: Mast cell number should not be considered a reliable factor in the differential diagnosis of LPL and CLL when assessing bone marrow histology. Possible bias towards κ light chain expression in LPL requires further study, as do the mechanism and functions of mast cell recruitment by neoplastic lymphoid cells.
Immunohistochemical localization of gross cystic disease fluid protein‐15, ‐24 and ‐44 in ductal carcinoma in situ of the breast: relationship to the degree of differentiation
Authors: Selim A A , El‐Ayat G , Wells C A
Published: March 2003

Immunohistochemical localization of gross cystic disease fluid protein‐15, ‐24 and ‐44 in ductal carcinoma in situ of the breast: relationship to the degree of differentiation

Aims: Three major proteins present in breast gross cystic disease fluid and expressed by the cyst lining apocrine epithelium are gross cystic disease fluid protein‐15 (GCDFP‐15), apolipoprotein‐D (APO‐D; GCDFP‐24) and zinc α2‐glycoprotein (ZnGP; GCDFP‐44). The aim of this study was to investigate the expression of these proteins in ductal carcinoma in situ (DCIS) of the breast and to relate their expression with the degree of differentiation of DCIS.

Methods and results: An immunohistochemical study of these proteins was performed in 57 cases of DCIS and nine cases of morphologically apocrine DCIS. Positivity was seen in 24/57 (42.1%) cases with anti‐GCDFP‐15, 20/57 (35.1%) cases with anti‐GCDFP‐24 and 22/57 (38.6%) cases with anti‐GCDFP‐44. GCDFP‐15 positivity was noted in 5/13 (38.5%) of the well‐differentiated, 11/19 (57.9%) intermediately differentiated and 8/25 (32.0%) of the poorly differentiated cases (P=0.217). GCDFP‐24 positivity was seen in 3/13 (23.0%) well‐differentiated, 9/19 (47.4%) intermediately differentiated and 8/25 (32.0%) poorly differentiated cases (P=0.336). GCDFP‐44 was detected in 5/13 (38.5%) of well‐differentiated cases, 11/19 (57.9%) intermediately differentiated and 6/25 (24.0%) poorly differentiated cases (P=0.074). In the nine cases of apocrine DCIS, GCDFP‐15 positivity was detected in seven (77.8%), while five (55.6%) and six (66.7%) cases were positive for GCDFP‐24 and GCDFP‐44, respectively.

Conclusions: The results indicate that there is no significant association between the expression of the studied proteins and the degree of differentiation of DCIS of the breast. Moreover, some morphologically apocrine DCIS cases appear to lose expression of these proteins.
Cellular myxoma of soft tissue: a clinicopathological study of 38 cases confirming indolent clinical behaviour
Authors: Van Roggen J F G , McMenamin M E , Fletcher C D M
Published: March 2003

Cellular myxoma of soft tissue: a clinicopathological study of 38 cases confirming indolent clinical behaviour

Aims: To characterize the clinicopathological features and biological potential of a group of soft tissue lesions with morphology intermediate between intramuscular myxoma and low‐grade myxofibrosarcoma.

Methods and results: Thirty‐eight lesions in 37 patients were retrieved from the authors’ consultation files. Clinical and follow‐up data were obtained and the lesions were also studied immunohistochemically. Tumours occurred in adults aged 25–83 years (mean 51.9 years) with a slight predominance in females. All cases, except two, were solitary. The extremities were preferentially involved (18 lower limb; nine upper limb), with seven lesions arising around the upper (2/7) and lower limb (5/7) girdles and four lesions occurring at other locations. Twenty‐nine of 31 of the tumours, for which the depth was known, were situated deep to the superficial fascia, although only 19 were strictly intramuscular. Histologically these lesions were both more cellular and more vascular than intramuscular myxoma, while lacking the cytological pleomorphism, nuclear atypia and curvilinear vascular pattern characteristic of low‐grade myxofibrosarcoma. CD34 positivity in lesional cells was identified in 17/30 (57%) cases, probably reflecting their fibroblastic nature. Staining for α‐smooth muscle actin was focally positive in 3/30 (10%) cases, while desmin and S100 protein staining were consistently negative. Clinical follow‐up data (available in 22 cases; median duration 30 months) demonstrate that these lesions behave in a benign fashion with only a small risk of local recurrence if not excised completely; in this study only two tumours recurred, both of which originally had been incompletely excised. None metastasized.

Conclusions: The risk of recurrence in this group of lesions which we have designated ‘cellular myxoma’ appears to be low. Consequently simple complete local excision is most often adequate treatment. Longer follow‐up (5–10 years or more) in a larger number of cases will be important in more definitively confirming the natural history of these lesions.
Recent advances in the pathology of smooth muscle tumours of the uterus
Authors: Wilkinson N , Rollason T P
Published: March 2003

Recent advances in the pathology of smooth muscle tumours of the uterus

Smooth muscle tumours of the uterus are common and the majority are benign leiomyomas. However, there are some tumours which exhibit unusual morphological features or growth patterns that cause difficulty in their distinction from malignant neoplasms and those with endometrial stromal differentiation. Such lesions are reviewed in this article with detailed descriptions of their morphology, differential diagnosis and correlation with biological behaviour.
Extranodal mantle cell lymphoma mimicking marginal zone cell lymphoma
Authors: Anagnostopoulos I , Foss H‐D , Hummel M , Trenn G , Stein H
Published: March 2003

Extranodal mantle cell lymphoma mimicking marginal zone cell lymphoma

Aim: We report a case of mantle cell lymphoma masquerading as a marginal zone cell lymphoma.

Methods and results: In the initial manifestation in the palatine tonsils, the neoplastic cells were found to grow exclusively within the marginal zones of secondary follicles which showed a preserved mantle zone. The few immunostains performed showed a B‐cell phenotype including an immunoglobulin light chain restriction. The extranodal manifestation, the growth pattern, and the immunophenotype led to the diagnosis of an extranodal marginal zone B‐cell non‐Hodgkin’s lymphoma (NHL). The specimen from the relapse occurring 8 months later exhibited diffuse monomorphous cells co‐expressing B‐cell antigens and CD5, CD43 and cyclin D1, leading to the diagnosis of mantle cell lymphoma. Re‐investigation of the initial biopsy revealed that the neoplastic cells within the marginal zones had a mantle cell lymphoma immunophenotype expressing cyclin D1, the immunoglobulin heavy chains IgD and IgM and partly CD5. Both lesions harboured identical clonal immunoglobulin gene rearrangements proving that they represented different manifestations of the same lymphoma.

Conclusion: This case emphasizes the importance of broad immunohistological investigation of B‐cell NHLs involving the marginal zone.
Neuroendocrine differentiation and prognosis in breast adenocarcinoma
Authors: Miremadi A , Pinder S E , Lee A H S , Bell J A , Paish E C , Wencyk P , Elston C W , Nicholson R I , Blamey R W , Robertson J F , Ellis I O
Published: March 2003

Neuroendocrine differentiation and prognosis in breast adenocarcinoma

Aims: Neuroendocrine differentiation has been detected, and its prognostic value studied, in a number of common human carcinomas. To date there are few detailed studies examining its relevance in breast carcinoma. In this study we evaluate the frequency and prognostic importance of neuroendocrine differentiation in breast adenocarcinoma.

Methods and results: The presence of neuroendocrine differentiation, defined as positive reactivity for three markers, neuron‐specific enolase (NSE), chromogranin A and/or synaptophysin, has been evaluated in 99 patients with primary operable breast cancer using standard immunocytochemical techniques. A consecutive cohort of patients were selected from the Nottingham/Tenovus series. Comprehensive patient and tumour records have been maintained, and patients were followed up according to a defined protocol. Eighteen cases were positive for NSE, 10 for chromogranin A and 13 for synaptophysin. Eleven percent were positive with more than one neuroendocrine marker. No significant association was found between neuroendocrine differentiation and tumour size, grade, stage or the prevalence of vascular invasion. There was no significant difference in either overall or disease‐free survival between patients with or without neuroendocrine differentiation.

Conclusions: In this study we confirm that neuroendocrine differentiation can be identified in a subset (10–18%) of human breast carcinomas. This phenomenon appears to have no relationship to established prognostic factors or patient outcome.
Microscopic colitis with giant cells
Authors: Libbrecht L , Croes R , Ectors N , Staels F , Geboes K
Published: March 2003

Microscopic colitis with giant cells

Aims: Collagenous colitis and lymphocytic colitis are the two types of microscopic colitis with specific morphological features. In this report we describe a new histopathological subtype of microscopic colitis.

Methods and results: Colonoscopy in four patients with chronic watery diarrhoea showed no macroscopic abnormalities. The random biopsies from the colon showed subepithelial multinucleated giant cells in combination with the features of collagenous colitis in three patients and lymphocytic colitis in one patient. These multinucleated giant cells were positive for CD68. The density of macrophages was highest in the most superficial part of the lamina propria. In one patient, a previous biopsy showed features consistent with collagenous colitis without multinucleated giant cells. Treatment with budesonide led to the disappearance of diarrhoea in all four patients.

Conclusions: The clinical and histopathological features of the four presented patients indicate that there exists a histopathological subtype of microscopic colitis characterized by the presence of subepithelial multinucleated giant cells, which probably arise from fusion of subepithelial macrophages. Analysis of more patients with this histopathological subtype of microscopic colitis is necessary to determine whether they also form a clinically distinct group.
Clinicopathological prognostic factors in soft tissue leiomyosarcoma: a multivariate analysis
Authors: Miyajima K , Oda Y , Oshiro Y , Tamiya S , Kinukawa N , Masuda K , Tsuneyoshi M
Published: March 2003

Clinicopathological prognostic factors in soft tissue leiomyosarcoma: a multivariate analysis

Aims: Prognostic factors affecting survival in cases of leiomyosarcoma of soft parts were investigated in this study.

Methods and results: A retrospective study of 267 patients was carried out. This group comprised 142 females (53%) and 125 males (47%), whose ages ranged from 7 to 95 years (median 58 years). One hundred and five cases were superficially situated (arising from the skin or subcutis), while the remaining 162 cases were deeply situated (subfacial). Nineteen were cases of pleomorphic leiomyosarcoma where the diagnosis had been amended from malignant fibrous histiocytoma to leiomyosarcoma whilst under review. Of the 167 patients with follow‐up data, 83 died of leiomyosarcoma. In univariate analysis, depth, tumour size (≥50 mm), mitotic rate of >20 per 10 high‐power fields (HPF), tumour necrosis of >50% and a high stage according to the most recent American Joint Committee on Cancer (AJCC) staging for soft tissue sarcoma were found to lessen significantly the rate of survival (log rank test; P < 0.05). However, in multivariate analysis (Cox's proportional hazards model), tumour size and high AJCC stage were the only factors that were correlated independently with decreased survival.

Conclusions: This study indicates that the most reliable prognostic parameters are tumour size and AJCC stage in leiomyosarcoma.
Intraepidermal cytokeratin 7 immunoreactive cells in the non‐neoplastic nipple may represent interepithelial extension of lactiferous duct cells
Authors: Yao D X , Hoda S A , Chiu A , Ying L , Rosen P P
Published: March 2003

Intraepidermal cytokeratin 7 immunoreactive cells in the non‐neoplastic nipple may represent interepithelial extension of lactiferous duct cells

Aims: The interpretation of cytokeratin 7 (CK7)‐positive cells in the epidermis of the nipple has been controversial. These cells have been described in Paget's disease of the nipple, and they have also been cited as benign `Toker' cells or as Merkel cells. Having observed CK7+ cells in histologically unremarkable nipple biopsies, we sought to assess the distribution of CK7+ cells in Paget's disease of the nipple and in histologically unremarkable nipple.

Methods and results: Representative sections from 37 cases of Paget's disease of the nipple and 32 cases of histologically unremarkable nipple were obtained. The histologically unremarkable nipple sections were taken from prophylactic mastectomies (n=17) and from autopsies of patients who did not have breast cancer (n=15). CK7 immunostaining was performed on sections from formalin‐fixed paraffin blocks. Sequential sections were immunostained with antibodies to low‐molecular weight cytokeratin‐CAM 5.2 and HER‐2/neu. CK7+ cells were present in the epidermis around the opening of the lactiferous ducts in Paget's disease (95%) and in histologically unremarkable nipple (45%) cases. CK7+ cells diminished in number with increasing distance from the orifice of the lactiferous ducts. The lactiferous duct epithelium in Paget's disease and in histologically unremarkable nipple was CK7+ in all specimens when this element was present. CAM5.2 immunostaining had a similar but weaker pattern of reactivity. HER‐2/neu reactivity was seen in 68% cases of Paget's disease and was negative in all cases of histologically unremarkable nipple. Tumour cells in two cases of Paget's disease were CK7−. In one of these, the underlying breast carcinoma was also CK7−, the only CK7− tumour in this series. In the other case, the normal lactiferous duct was CK7+ and no underlying carcinomatous tissue was available to study.

Conclusions: The presence of CK7+ cells does not equate to Paget's disease of the nipple. Intraepidermal CK7+ cells in the non‐neoplastic nipple can be a manifestation of interepithelial extension of benign lactiferous duct cells. The increased presence of CK7+ cells in Paget's disease probably results either from neoplastic transformation of native intraepithelial lactiferous duct cells or form direct extension/migration of neoplastic cells into the nipple. The distribution of CK7 immunoreactive cells in the nipple epidermis can be helpful in the diagnosis of Paget's disease of the nipple.
Sinonasal haemangiopericytoma‐like tumour: a sinonasal glomus tumour or a haemangiopericytoma?
Authors: Tse L L Y , Chan J K C
Published: March 2003

Sinonasal haemangiopericytoma‐like tumour: a sinonasal glomus tumour or a haemangiopericytoma?

Aims: Sinonasal haemangiopericytoma‐like tumour is controversial with regard to its nosologic nature. This study aims to investigate its relationship with glomus tumour and haemangiopericytoma.

Methods and results: Six cases of sinonasal haemangiopericytoma‐like tumours identified in our files were reviewed for clinicopathological features, and compared with five cases each of soft tissue glomus tumour and meningeal haemangiopericytoma. Immunohistochemical studies for muscle‐specific actin, smooth muscle actin, desmin and CD34 were performed. Sinonasal haemangiopericytoma‐like tumour demonstrated a uniform histological appearance with bland‐looking short, spindly cells forming sheets and short fascicles. The tumour cells were interspersed with slit‐like, round and ectatic blood vessels. Actin immunoreactivity was demonstrated in all six cases, although occasionally patchy. The histological appearance and immunohistochemical phenotype of sinonasal haemangiopericytoma‐like tumour were very similar to and focally indistinguishable from glomus tumour. Meningeal haemangiopericytoma, in contrast, was characterized by high tumour cellularity, random nuclear orientation, presence of staghorn vasculature and lack of immunohistochemical evidence of myogenic differentiation.

Conclusions: We conclude that sinonasal haemangiopericytoma‐like tumour is biologically close to or identical to glomus tumour, but is not related to haemangiopericytoma.
Cytokeratin 7: a useful adjunct in the diagnosis of chromophobe renal cell carcinoma
Authors: Mathers M E , Pollock A M , Marsh C , O'Donnell M
Published: March 2003

Cytokeratin 7: a useful adjunct in the diagnosis of chromophobe renal cell carcinoma

Aims: The histopathological diagnosis of chromophobe renal cell carcinoma can present a diagnostic challenge, as these tumours can resemble either conventional renal cell carcinoma or oncocytoma. The aim of this study was to determine whether cytokeratin 7 expression is of practical use in the distinction of these three entities.

Methods and results: A total of 40 cases previously diagnosed as either chromophobe renal cell carcinoma, conventional renal cell carcinoma or oncocytoma were identified. A representative section of each was stained with H&E and cytokeratin 7. Following independent review of the cases by three pathologists, a consensus diagnosis for each case was reached and the pattern of cytokeratin 7 staining was assessed. There were 12 cases of chromophobe renal cell carcinoma in the study, all of which showed a characteristic peripheral membrane pattern of staining for cytokeratin 7. Seventeen of the 18 cases of conventional renal cell carcinoma studied were negative for cytokeratin 7, while one case showed weak focal staining of <5% of the cells. The 10 cases of oncocytoma showed patchy weak to moderate cytoplasmic expression of cytokeratin 7, without the characteristic peripheral membrane accentuation seen in the chromophobe carcinomas.

Conclusions: Immunohistochemical staining for cytokeratin 7 appears to be a useful adjunct in the diagnosis of chromophobe renal cell carcinoma, and in distinguishing this tumour from both oncocytoma and conventional renal cell carcinoma.
Extrauterine placental site trophoblastic tumour in association with a lithopedion
Authors: El Hag I A , Ramesh K , Kollur S M , Salem M
Published: March 2003

Aim:  We describe an unusual case of extrauterine placental site trophoblastic tumour located in pouch of Douglas in association with a lithopedion.

Methods and results:  A 35‐year‐old female presented with acute abdomen and peritonitis following rectal perforation. The patient gave a history of 5 months amenorrhoea followed by vaginal bleeding 5 years prior to admission. At laparotomy, a lithopedion was found in pouch of Douglas with rectal perforation and peritonitis. The lithopedion was removed, rectal perforation was sutured and a colostomy was performed. The colostomy was closed later and tumour was seen in the colostomy wound as well as attached to the lithopedion removed previously. The patient presented with a repeated episode of rectal perforation and the tumour had spread to colon, small intestine, omentum, mesentery and right ovary.

Conclusion:  A high‐grade malignant placental site trophoblastic tumour with aggressive clinical course occurred at an extrauterine site. It complicated calcified abdominal pregnancy and resulted in repeated rectal perforation and peritonitis.
High expression of markers of apoptosis in Langerhans cell histiocytosis
Authors: Petersen B L , Rengtved P , Bank M I , Carstensen H
Published: March 2003

Aims:  Langerhans cell histiocytosis is a rare disease with clonal proliferation of dendritic histiocytes, occurring most frequently in infancy and early childhood. In the localized form (single system), the disease is self‐limiting, but in the cases of multisystem disease a third of the patients develop organ dysfunction. In these cases the prognosis is poor. Our objective has been to study the immunohistochemical expression of Fas and Fas‐ligand (Fas‐L) in order to determine whether the level of expression of these proteins could predict the outcome of the disease. We also wanted to determine the number of apoptotic cells to compare with the expression of Fas and Fas‐L.

Methods and results:  We analysed the expression of Fas and Fas‐L in 76 infiltrates from 49 paediatric patients with Langerhans cell histiocytosis. We also compared the results with the expression of the tumour suppressor protein p53 and the number of cells in apoptosis detected with TUNEL. Langerhans cell histiocytosis cells showed strong expression of p53 and in some cases co‐expression of Fas and Fas‐L. The expression of Fas‐L was significantly higher in infiltrates from patients with single‐system disease. The actual number of pathological Langerhans cells in apoptosis as estimated by TUNEL was low.

Conclusions:  The low number of TUNEL‐reactive cells can be explained by the rapid turnover of apoptotic cells in the tissue, not leaving the apoptotic cells long enough in the tissue to be detected. The co‐expression of Fas and Fas‐L in some Langerhans cells can lead to an autocrine apoptotic shortcut, mediating the death of the double‐positive cells. Our findings suggest that apoptosis mediated through the Fas/Fas‐L pathway may contribute to the spontaneous regression of lesions in single‐system disease. A delicate balance between autocrine death and survival of Langerhans cells may have been disturbed in patients with multisystem lesions.
The CD4+ T‐cell response to protein immunization is independent of accompanying IFN‐γ‐producing CD8+ T cells
Authors: DOYLE  , RAMM  , KELSO
Published: March 2003

By virtue of their strong bias towards production of interferon‐γ (IFN‐γ), CD8+ T cells have the potential to promote the development of type 1 immune responses. We have previously shown that the CD4+ T‐cell response to immunization with the protein antigen keyhole limpet haemocyanin (KLH) has a mixed interleukin‐4 (IL‐4)/IFN‐γ production profile. Here we show that this immunization regimen also stimulates accumulation in the draining lymph nodes of CD8+ T cells, which preferentially contain IFN‐γ mRNA ex vivo and secrete IFN‐γ protein in vitro. This provides a model to test whether CD8+ cell‐derived IFN‐γ participates in the normal control of the immune response to a non‐viable exogenous antigen. To investigate regulation of the anti‐KLH response by the CD8+ population or IFN‐γ produced by this or other cell types, mice were administered depleting antibodies. Depletion of CD8+ cells had no effect on the frequency of clonogenic KLH‐specific CD4+ T cells, the IL‐4/IFN‐γ profiles of their progeny, or the isotype profiles of the serum antibody response to KLH. In contrast, IFN‐γ neutralization diminished cell accumulation in the lymph nodes and reduced both the frequency of KLH‐specific CD4+ T cells that gave rise to IFN‐γ‐producing clones and serum titres of KLH‐specific IgG2a and IgG3. Therefore, despite the potential for cross‐regulation, the CD4+ T‐cell response to this immunogen is independent of the IFN‐γ‐skewed CD8+ response.
Post‐translational modification and intracellular localization of a splice product of CD46 cloned from human testis: role of the intracellular domains in O‐glycosylation
Authors: HARA  , SUZUKI  , NAKAZAWA  , NISHIMURA  , NAGASAWA  , NISHIGUCHI  , MATSUMOTO  , HATANAKA  , KITAMURA  , SEYA
Published: March 2003

We obtained a unique CD46 cDNA, STc/CY4, from the human testis, the predicted amino acid sequence of which suggested the presence of a novel isoform of CD46. This message was present predominantly in the testis, andthe predicted isoform possessed a short (11 amino acids) transmembrane section (TM) and an unidentified cytoplasmic tail (CY). When expressed in Chinese hamster ovary (CHO) cells, this CD46 isoform underwent no O‐glycosylation and was mostly retained in the endoplasmic reticulum. This unusual behaviour of the new isoform was due in part to the short TM and the unusual sequences of the CY. The molecular mass of this isoform was 42 000, approximately 20 000 smaller than conventional CD46. These properties of the STc/CY4 isoform were similar to those of sperm CD46. The only difference between sperm CD46 and the STc/CY4 isoform expressed on CHO cells was that only the latter possessed N‐linked sugars of high mannose types. Since the STc/CY4 isoform may behave like sperm CD46 in cellular localization and post‐translational modification, studies of sperm–egg interassociation were performed using hamster eggs and CHO cell clones expressing various isoforms including the STc/CY4. Rosette formation was seen most effectively between hamster eggs and STc/CY4‐expressing CHO cells. These results infer that O‐glycosylation perturbs CD46‐mediated sperm‐binding to eggs and thus sperm CD46 lacking O‐linked sugars can serve as an adhesion molecule. The possible role of CD46 in fertilization and the structural differences between sperm and conventional CD46 are discussed.
Fas ligand (FasL, CD95L, APO‐1L) expression in murine mast cells
Authors: WAGELIE‐STEFFEN  , HARTMANN  , VLIAGOFTIS  , METCALFE
Published: March 2003

Fas ligand (FasL, CD95L, Apo‐1L), a type II membrane protein belonging to the tumour necrosis factor family, induces apoptosis in Fas‐bearing cells. As murine mast cells have been shown to express Fas antigen, we hypothesized that mast cells might also express FasL. To explore this possibility, we first demonstrated FasL mRNA in mast cells by reverse transcription–polymerase chain reaction and FasL protein by immunoblot analysis. FasL protein was shown to be exclusively located within the cell by flow cytometry. In agreement with this observation, bone marrow cultured mast cells were unable to kill Jurkat T cells. Our results demonstrate that FasL is expressed in murine mast cells and suggest that this murine mast cell FasL is not lytic, owing to the intracellular localization.
MAPkinase: a second site of G‐protein regulation of B‐cell activation via the antigen receptors
Authors: DEEHAN  , KLAUS  , HOLMAN  , HARNETT  , HARNETT
Published: March 2003

Ligation of the antigen receptors on B cells transduces transmembrane signals leading to the induction of DNA synthesis. We now show that a pertussis toxin‐sensitive heterotrimeric G‐protein(s) of the Gi class plays a key role in the regulation of surface immunoglobulin (sIg)‐mediated DNA synthesis in B cells. This site of G‐protein regulation is distinct from that we have previously reported to govern the coupling of the antigen receptors on B cells to the phospholipase C‐mediated hydrolysis of phosphatidylinositol‐4,5‐bisphosphate. We have, moreover, identified a candidate target for this new G‐protein regulation by showing that mitogen‐activating protein kinase (MAPkinase) activity, which plays a key role in the transduction of sIg‐mediated proliferative signals in B cells, is abrogated by pre‐exposure to pertussis toxin that covalently modifies and inactivates heterotrimeric G‐proteins of the Gi class. Furthermore, our data suggest that this pertussis toxin‐sensitive G‐protein couples the antigen receptors to MAPkinase activation, at least in part, by regulating sIg‐coupling to Lyn, Syk and perhaps Blk and Fyn activity, results consistent with studies in other systems which show that classical G‐protein‐coupled receptors recruit such protein tyrosine kinases to tranduce MAPkinase activation. Interestingly, however, this G‐protein plays no apparent role in the control of up‐regulation of major histocompatibility complex class II expression on B cells, suggesting that such G‐protein‐regulated‐tyrosine kinase and MAPkinase activation is not required for the induction of this biological response following antigen receptor ligation.
Expression of CD2 on porcine B lymphocytes
Authors: ŠINKORA  , ŘEHÁKOVÁ  , ŠINKORA  , CUKROWSKA  , TLASKALOVÁ‐HOGENOVÁ  , BIANCHI  , DE GEUS
Published: March 2003

Remarkable interspecies differences in CD2 expression on B lymphocytes have been reported in mammals. Human and rat B cells lack CD2, whilst B lymphocytes in mice are CD2+. In pigs, B cells have been supposed not to express CD2. We show here, however, that CD2 is present at a low level on a prominent subset of porcine B cells. Moreover, we describe changes in the proportions of CD2+ and CD2− B‐cell subsets during ontogeny. Before contact with microflora, the majority of peripheral surface immunoglobulin M+ (sIgM+) B cells express CD2 and sIgM+CD2− B cells are rare. Shortly after colonization of conventional (CV) piglets with complex intestinal microflora, numerous CD2−B cells appear in the periphery and their relative number increases with age in both CV and specific pathogen‐free (SPF) pigs. However, monoassociation of germ‐free (GF) piglets with a single Escherichia coli strain does not result in a significant increase of sIgM+CD2−B cells in the periphery. We suggest that CD2 is down‐regulated in porcine B lymphocytes upon activation with microflora in mucosa‐associated lymphatic tissues. In bone marrow (BM), we identified putative porcine B‐cell precursors. These cells express CD2 at low density and do not bear either the common myelomonocytic antigen or T and B‐lymphocyte receptors. Similar to mouse and human pre‐B cells, this lymphocyte‐sized subset expresses CD25 and class II antigens. CD2 positivity of these cells indicates that CD2 is expressed earlier than sIgM during B lymphopoiesis in pigs.
Prenatal ontogeny of lymphocyte subpopulations in pigs
Authors: ŠINKORA  , ŠINKORA  , ŘEHÁKOVÁ  , ŠPLÍCHAL  , YANG  , PARKHOUSE  , TREBICHAVSKÝ
Published: March 2003

Although porcine lymphocytes have been classified into numerous subpopulations in postnatal animals, little is known about the ontogeny of these complex cell subsets. Using double‐ and triple‐colour flow cytometry (FCM), we investigated the surface phenotype of fetal lymphoid cells in the thymus, cord blood, spleen and mesenteric lymph nodes at different stages of gestation. It was found that the major lymphocyte subpopulations started to appear at the beginning of the second third of the gestation period, with B cells being the earliest lymphocyte subpopulation to appear in the periphery. The T‐cell receptor (TCR) γδ+ cells were the earliest detectable T‐cell subset, developing first in the thymus and subsequently arriving in the periphery. Later in ontogeny, however, the number of TCRαβ+ lymphocytes rapidly increased, becoming the predominant T cells both in the thymus and in the periphery. Cells with the phenotype of adult natural killer cells were also identified in pig fetuses, though their nature and functional roles remain to be investigated. In addition, CD2 was expressed on most B cells whilst very few CD4+ TCRαβ+ cells or CD2+ TCRγδ+ cells expressed CD8, suggesting that the expression of CD2 and CD8 may reflect the functional status of the cells in postnatal animals. Taken together, this study has provided a systematic analysis of fetal porcine lymphocyte subpopulations and may provide the base for studies to establish the physiological roles of these lymphocyte subsets.
38 000 MW antigen‐specific major histocompatibility complex class I restricted interferon‐γ‐secreting CD8+ T cells in healthy contacts of tuberculosis
Authors: WILKINSON  , ZHU  , WILKINSON  , LALVANI  , IVANYI  , PASVOL  , VORDERMEIER
Published: March 2003

CD8+ T lymphocytes are required to protect mice against Mycobacterium tuberculosis, although in early infection the mechanism appears not to be via perforin or granzyme‐mediated lysis of the infected target, and may be via interferon‐γ (IFN‐γ) production. We therefore investigated whether CD8+ T cells specific for the immunoprotective 38 000 MW antigen of M. tuberculosis could be detected in infected humans. Using a recombinant vaccinia virus expressing the 38 000 MW antigen of M. tuberculosis (rV38) and a control vaccinia virus (rVras) we demonstrated that both viruses stimulated IFN‐γ production from freshly isolated peripheral blood mononuclear cells (PBMC) in a 36‐hr enzyme‐linked immunospot assay. Cell depletion and antibody blockade established that the bulk of the 38 000 MW antigen‐specific IFN‐γ response was mediated by CD8+, major histocompatibility complex class I‐restricted T cells, whereas the anti‐vaccinia virus response was predominantly mediated by CD4+ T cells. In further evaluations PBMC from all seven healthy tuberculosis‐exposed contacts had a 38 000 MW antigen‐specific IFN‐γ response, whereas seven patients with untreated sputum‐positive pulmonary tuberculosis had very low levels of 38 000 antigen‐specific IFN‐γ‐producing cells. These preliminary observations demonstrate the utility of recombinant vaccinia viruses in restimulating freshly isolated CD4+ and CD8+ T cells. The bias towards a higher frequency of IFN‐γ‐producing CD8+ T cells in contacts rather than patients may indicate a protective role for CD8+ cells in human tuberculosis.
Co‐ordinate expression of the pre‐T‐cell receptor complex and a novel immature thymocyte‐specific antigen, IMT‐1, during thymocyte development
Authors: TONG  , KISHI  , NAGATA  , MURAGUCHI
Published: March 2003

Previously we described a monoclonal antibody (mAb) that reacted with a cell‐surface antigen, immature thymocyte antigen‐1 (IMT‐1), which is expressed on thymocytes of late CD4− CD8− (double negative) to early CD4+ CD8+ (double positive) differentiation stages. In this study, we investigated the expression of IMT‐1 on various cell lineages in thymus as well as in peripheral lymphoid organs. We found that IMT‐1 is expressed on T‐cell receptor (TCR)‐βlo and TCR‐δlo thymocytes, but not on TCR‐βhi, TCR‐δhi or natural killer (NK)1.1+ thymocytes, or on peripheral αβ or γδ T cells. We also investigated the kinetics of expression of IMT‐1 during fetal thymocyte development and compared it with the expression of the pre‐TCR complex, comprising CD3, pre‐TCR‐α (pTα) and TCR‐β. We found that expression of both was similar, starting at day 14·5 of gestation, peaking on day 16·5 and gradually decreasing thereafter. Furthermore, the expression of both IMT‐1 and pTα was drastically reduced when DN thymocytes in recombination activating gene (RAG)‐2−/− mice were challenged in vivo with anti‐CD3 mAb. These results indicate that IMT‐1 is expressed on not only immature thymocytes of αβ T‐cell lineage but also on those of γδ T‐cell lineage, and that the expression of IMT‐1 and the pre‐TCR complex is co‐ordinately regulated during the αβ lineage thymocyte development.
Surface‐expressed invariant chain (CD74) is required for internalization of human leucocyte antigen‐DR molecules to early endosomal compartments
Authors: MOLDENHAUER  , HENNE  , KARHAUSEN  , MÖLLER
Published: March 2003

Transport of major histocompatibility complex (MHC) class II molecules to the endocytic route is directed by the associated invariant chain (Ii). In the endocytic pathway, Ii is proteolytically cleaved and, upon removal of residual Ii fragments, class II αβ dimers are charged with antigenic peptide and recognized by CD4+ T cells. Although distinct peptide‐loading compartments such as MIIC (MHC class II loading compartment) and CIIV (MHC class II vesicles) have been characterized in different cells, there is growing evidence of a multitude of subcellular compartments in which antigenic peptide loading takes place. We employed a physiological cellular system in which surface Ii (CD74) and surface human leucocyte antigen (HLA)‐DR were induced either alone or in combination. This was achieved by transient exposure of HT‐29 cells to recombinant interferon‐γ (rIFN‐γ). Using distinct cellular variants, we showed that: (i) the majority of Ii molecules physically associate on the cell membrane with class II dimers to form DR αβ:Ii complexes; (ii) the presence of surface Ii is a prerequisite for the rapid uptake of HLA‐DR‐specific monoclonal antibodies into early endosomes because only the surface DR+/Ii+ phenotype, and not the DR+/Ii− variant, efficiently internalizes; and (iii) the HLA‐DR:Ii complexes are targeted to early endosomes, as indicated by co‐localization with the GTPase, Rab5, and endocytosed bovine serum albumin. Internalization of HLA‐DR:Ii complexes, accommodation of peptides by DR αβ heterodimers in early endosomes and recycling to the cell surface may be a mechanism used to increase the peptide repertoire that antigen‐presenting cells display to MHC class II‐restricted T cells.