bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vascular Pseudoinvasion: A Case Report and Review of Literature
Authors: Agarwal Anupma , Wu Hueizhi 
Published: September 2019

Abstract
In the era of minimally invasive procedures, laparoscopic hysterectomy is preferred over total abdominal hysterectomy as the primary treatment of endometrioid cancer limited to the uterus. Lymphovascular invasion (LVSI) is an important prognostic indicator for this tumor. Studies have observed presence of vascular pseudoinvasion in the surgical specimen excised via laparoscopic hysterectomy. Some studies have reported no increase in LVSI after minimally invasive surgery, implying that there is no vascular pseudoinvasion. Here, we present a 59-year-old female with history of obesity, hypertension, diabetes mellitus, asthma, and biopsy-proven well-differentiated endometrioid adenocarcinoma who underwent total laparoscopic hysterectomy with bilateral salpingo-oophorectomy and sentinel node dissection. An ill-defined friable mass (2.1 cm in maximum dimension) was present in the posterior lower uterine segment and had the morphology of endometrioid adenocarcinoma, grade 1 out of 3, invasive into the outer half of myometrium. There was no true vessel invasion but rather abundant contamination—smearing of tumor into vascular spaces. An immunostain for D2-40 identified no lymphatic invasion. Immunostains for CD31 and CD34 highlighted tumor cells present in vascular spaces consistent with pseudoinvasion. No regional lymph node metastasis was seen. Peritoneal fluid did not show malignant cells. After surgery, the patient received radiotherapy and had no evidence of recurrent disease. It has been proposed that the artifact of vascular invasion as seen in our case could be associated with the technique of laparoscopic hysterectomy. Substantial LVSI, in contrast to focal or no LVSI, has been shown to be the strongest independent prognostic factor for pelvic regional recurrence, distant metastasis, and overall survival. Its presence is a deciding factor for the type of adjuvant therapy. Therefore, it is important to recognize vascular pseudoinvasion to avoid misdiagnosis of LVSI.
Parasitic Leiomyoma After Laparoscopic Total Hysterectomy and Bilateral Salpingo-Oophorectomy, a Mimicker of Pelvic Neoplasm
Authors: Song Weihua , Asuzu Ifeyinwa , Villanueva Jocelyn 
Published: September 2019

Abstract
Parasitic leiomyomas are rare occurrences that may mimic malignancy and thus present a diagnostic dilemma. They are thought to arise from a pedunculated subserosal leiomyoma that undergoes torsion and detaches from the uterus, surviving by revascularization from adjacent structures, or from iatrogenic implantation during surgery, more common with the clinical popularity of laparoscopic surgery and power morcellation. We report a case of parasitic leiomyoma with degenerative changes in a 57-year-old female who was initially found to have a 6.5-cm left adnexal mass and multiple submucosal and intramural masses consistent with leiomyoma by abdominal pelvic computerized tomography test (CT) 7 years prior to presentation. She experienced severe abdominal discomfort that persisted after total abdominal hysterectomy and a 7.8-cm mass was found in the left pelvic cavity on reevaluation. Grossly, the pelvic mass was a 6.5-cm tan-gray ovoid firm mass with a 4.0-cm cystic cavity. The cut surfaces of the solid areas/cyst wall were gray-white and firm with focal yellow streaks. Microscopically, there was central cystic degeneration, with cyst wall showing extensive granulation tissue. The solid portion also showed extensive hyaline degeneration, fibrosis, and perinodular hydropic degeneration. Smooth muscle differentiation was evident at the periphery of the mass, confirmed by strong staining with desmin and smooth muscle actin. This represents a parasitic leiomyoma left behind following the first procedure and it developed degenerative changes. In addition to the high index of suspicion for malignancy in assessing adnexal masses, degenerating parasitic leiomyomas should be included in the differential diagnosis of such mass lesions.
Mcl-1 Expression May Be Associated With Favorable Clinical Outcome in BRAF V600E–Mutated MMR-Deficient Colorectal Cancers
Authors: Zhang Xin , Findeis-Hosey Jennifer , Sharma Meenal , Gonzalez Raul , Amorese Rebecca , Gupta Elena , Foor-Pessin Caitlin , Frado Laura , Marino Danielle , DeCross Arthur , Yang Qi , Hiroshige Karina , Huber Aaron 
Published: September 2019

Abstract

Objectives
The BRAF V600E mutation is associated with treatment resistance and is a poor prognostic indicator in colorectal adenocarcinomas (CRAs). Prior studies have shown that the BRAF V600E mutation confers resistance to apoptosis by Mcl-1 gene upregulation. We evaluated the clinical effect of Mcl-1 expression on BRAF-mutated (BM) MMR-deficient (dMMR) CRAs.

Methods
Thirty-one BM dMMR CRAs were included in a tissue microarray. The intensity and extent of Mcl-1 expression were evaluated by immunohistochemistry. Staining intensity (0-3+) and percentage of cells with positive staining (none, <10% = 1, 10%-50% = 2, and >50% = 3) were determined. Cases were considered positive when the intensity score multiplied by the percentage category score was >4. Mcl-1 expression was correlated with clinicopathologic features.

Results
Positive Mcl-1 staining was identified in 13 (42%), among which 9 (69.2%) were well to moderately differentiated with lymphovascular invasion present in 4 (30.8%), lymph nodes metastases in 3 (23.1%), and AJCC stage pT3 or greater in 8 (61.5%). In contrast, 18 (58%) were Mcl-1 negative, among which 10 (55.6%) were poorly differentiated with lymphovascular invasion present in 12 (66.7%), lymph node metastases in 9 (50%), and AJCC stage pT3 or greater in 14 (77.8%).

Conclusion
Among 31 examined BM dMMR CRAs, cases that demonstrated Mcl-1 expression were associated with a lower grade, lower rate of lymphovascular invasion and lymph node metastasis, and lower AJCC stage. While Mcl-1 expression confers resistance to apoptosis, this study suggests that Mcl-1–positive tumors demonstrate pathologic features associated with a favorable clinical outcome.
Spontaneous Complete Regression of Testicular Germ Cell Tumor: A Case Report
Authors: Liu S Shawn , Hernandez Sara Avalos , Zotto Valeria Dal , Herrera Guillermo 
Published: September 2019

Abstract
Testicular germ cell tumors (TGCTs) may spontaneously regress, making it a diagnostic challenge. We present here a case of 39-year-old African American male with constant abdominal pain radiating into the back. Computed tomography identified bulky retroperitoneal lymphadenopathy. There was no history of testicular trauma. Ultrasonography of right testicle revealed multiple microcalcifications, and a laboratory test indicated elevated beta-hCG and LDH. Patient underwent right orchiectomy, which revealed a grossly well-demarcated white oval lesion (3.1 cm). Histologic examination identified a fibrotic lesion in a background of atrophic parenchyma consistent with scar tissue. The specimen was completely submitted for microscopic evaluation, but neoplasia was not identified. A placental alkaline phosphatase (PLAP) immunohistochemical stain failed to reveal residual germ cell neoplasm in situ. Biopsy of retroperitoneal lymph node identified malignant neoplastic cells expressing PLAP, CD117, CD30, and cytokeratin AE1/AE3. The morphology and immunophenotype were consistent with metastatic germ cell tumor. Spontaneous regression of TGCT is defined as partial or complete tumor disappearance without any treatment. The clinical presentation could be nonspecific. Histologically, tumor regression is indicated by formation of fibrous scar, testicular atrophy, microcalcification, lymphoplasmacytic infiltration, and hemosiderin-phagocytosed macrophages, all of which were present in the current case. However, similar histological features could be identified in testicular ischemia or infraction. Therefore, the diagnosis of complete regression of TGCT is challenging and frequently relies on the present of extragonadal germ cell tumor. In the current case, we reported a spontaneous complete regression of TGCT, supported by a spectrum of histological features and metastasis to retroperitoneal lymph node. Spontaneous regression of TGCT is rare, with less than 150 cases reported in the literature. Since there is a lack of definitive histologic criteria to diagnose complete spontaneous regression of TGCT, when scarring is seen in the testis, additional clinical and imaging evaluation should be followed.
Common Etiologies and Clinical Significance of Gastric Intraepithelial Lymphocytosis
Authors: Ahmed Sunjida , Xu Ruliang 
Published: September 2019

Abstract

Background
Increased intraepithelial lymphocytes or intraepithelial lymphocytosis (IEL) in the upper gastrointestinal (GI) tract is a response to various mucosal injury. However, the frequency of gastric IEL in GI tract biopsy is not well documented, and the etiologies of gastric IEL are yet to be defined.

Methods
Cases with a diagnosis of “intraepithelial lymphocytosis” and “intraepithelial lymphocytes” were retrieved from 25,074 GI biopsies and 8,921 partial gastrectomies in our departmental database (Powerpath) for a 1-year period. The diagnosis of IEL was confirmed by the report and/or slide review. Possible etiology or causes of gastric IEL were investigated by correlation with clinical information from LIS (EPIC).

Results
A total of 694 cases with IEL were identified from 33,995 GI tract specimens (biopsy and resection). Among 694 cases, 34 (4.89%) were gastric biopsy and resection cases with IEL, whereas 561 (80.8%), 37 (5.3%), and 62 (8.9%) were duodenal, esophageal, and colonic specimens, respectively. Thirty-four gastric cases with IEL were closely associated with morbid obesity (8, 23.5%), H pylori infection (8, 23.5%), celiac disease (5, 14.7%), lymphocytic gastritis (5, 14.7%), nonspecific gastritis (4, 11.4%), inflammatory bowel disease (3, 8.8%), and gastroesophageal reflux disease (1, 1.9%). Seventeen of 34 (50%) cases had IEL in both gastric and duodenal mucosa. Those 17 cases with gastroduodenal IEL had morbid obesity (n = 5), celiac disease (n = 5), lymphocytic colitis (n = 2), inflammatory bowel disease (n = 2), H pylori gastritis (n = 2), and nonspecific gastritis (n = 1). Five patients with a diagnosis of lymphocytic gastritis were treated with a protein pump inhibitor after pathologic diagnosis. Among them, 4 had a followed-up endoscopy in 12 months, and 3 of them showed persistent IEL in a follow-up biopsy.

Conclusion
Gastric IEL is less common than duodenal IEL. It is associated with a broad differential diagnosis. Follow-up biopsy may be necessary for some types of gastric IEL. Persistent IEL in follow-up biopsy may be suggestive of a different etiology or requires different treatment strategy.
A Diagnosis to Wrestle With: Intraventricular Angiomatoid Fibrous Histiocytoma
Authors: Canevari Margaux , Keenan Bryan , Horkayne-Szakaly Iren , Miettinen Markku 
Published: September 2019

Abstract
We report a case of a 15-year-old boy who presented with an intraventricular angiomatoid fibrous histiocytoma. The patient suffered a concussion during a wrestling match and underwent a head and spine CT, which prompted an MRI. MRI revealed an enhancing 2.3-cm mass in the posterior horn of the right lateral ventricle with no hydrocephalus. The patient subsequently admitted to having had headaches with associated appetite suppression but no visual problems or weakness. The tumor was resected. It was composed of sheets and cords of histiocytoid cells with focal pleomorphism. Interspersed throughout was a robust lymphoplasmacytic infiltration with Russell bodies and lymphoid follicles. The histiocytoid neoplastic cells were desmin, EMA, and sparsely S100 protein positive. They were negative for CD31, CD34, Cam 5.2, CD163, CD1a, HMB45, Melan-A, progesterone, and ERG. The abundant plasma cell population was confirmed by CD138 reactivity and was polyclonal by kappa and lambda immunohistochemistry. Fluorescence in situ hybridization revealed an EWSR gene rearrangement. The patient was radiographically free of disease 3 years after surgery with headaches as residual sequela. The differential diagnosis for this case included a lymphoplasmacyte-rich meningioma or a plasmacytoma. The EWSR rearrangement made both of these unlikely. The polyclonal nature of the plasma cell component and the age of the patient also argued against plasmacytoma. A literature search revealed one other ventricular-based angiomatoid fibrous histiocytoma in a pediatric patient.
Fecaloma Complicating Colostomy for Hirschprung Disease
Authors: Ohayi Samuel , Onyishi Nnaemeka , Chukwubuike Kevin 
Published: September 2019

Abstract

Background
Hirschprung disease (HD) is a congenital disorder characterized by absence of ganglion cells in the distal portion of the large intestine with resultant obstruction. It commonly manifests shortly after birth, hence its usual diagnosis in the first year of life. A defunctioning colostomy precedes definitive treatment. Prolonged obstruction following untreated HD or any condition may progressively lead to fecaloma, a mass of inspissated feces commonly in the rectosigmoid that is much harder than impacted feces. If prolonged, affected intestine looks like a tumor. We present a case of fecaloma of the transverse colon complicating colostomy done for Hirschprung disease.

Case Report
A 6-year-old boy with a 6-year history of difficulty with passing stool with progressive abdominal swelling had Swenson’s procedure (ie, proctectomy) and prolapsing of ganglionic colon to the anus with left hemicolectomy. He had presented to the pediatric surgery unit of our hospital 4 years previously with these symptoms with a defunctioning colostomy performed for suspected HD. He reportedly passed meconium a day after birth and subsequently passed stool once in 7 to 14 days spontaneously or after digital manipulations. Stooling frequency progressively reduced but no vomiting. Following administration of herbs, he developed diarrhea, and with worsening symptoms, he presented to our hospital. Three years postcolostomy, rectal biopsy was performed with a histology confirming aganglionosis of the rectum (HD). Barium enema had shown long-segment HD with dilated rectosigmoid colon but no fecaloma. Surgical specimen received in the histopathology laboratory consisted of colon segment comprising a colostomy stump with a ring of skin (colostomy stoma) and a proximal markedly dilated portion filled with fecaloma followed by a hypertrophied proximal portion. Histology showed presence of ganglion cells in these segments.

Conclusion
Fecaloma should be suspected in a protracted colostomy with abdominal mass proximal to the stoma.
Rare Testicular Neoplasm: Melanotic Neuroectodermal Tumor of Infancy
Authors: Canevari Margaux , Wang Larry , Rossi Christopher 
Published: September 2019

Abstract
We report the case of an 18-month-old boy who presented with a several-week history of left testicular swelling. On physical examination, the testicle was firm, enlarged, and nontender to palpation. The patient’s urinary habits and family history were unremarkable. An ultrasound was performed that revealed an enlarged left testis (4.7 cm) with a hypervascular heterogeneous appearance and scattered echogenic foci that raised concern for a neoplastic process. Microlithiasis was identified in the right testis (1.6 cm). AFP and hCG were within normal limits, and LDH was mildly elevated. An orchiectomy was performed and gross dissection revealed a 4.5 × 3.5 × 3.0-cm mass. The tumor was biphasic and composed of a population of poorly differentiated small round blue cells (neuroblastoma-like) and a separate component of nested epithelioid cells that had abundant cytoplasm with melanotic granules. Mitotic and karyorrhectic figures were scattered throughout. Epididymis infiltration was present. The epithelioid cells were pan-cytokeratin, EMA, and HMB-45 positive. The small round blue cells were positive for synaptophysin, vimentin, and CD117. A subpopulation was also moderately positive for CD99. A Phox2B and TDT were negative in the tumor cells, which helped to exclude neuroblastoma and lymphoma. The combined features of this case were diagnostic for melanotic neuroectodermal tumor of infancy (MNTI). This is a rare tumor with a strong predilection for the head and neck region with testicular/paratesticular localization accounting for less than 5% of MNTI cases. MNTIs are classically seen in infants under 1 year of age and typically behave in a benign fashion, although metastases to retroperitoneal lymph nodes and lymphatics have been documented. It is important to remember the differential of pediatric testicular neoplasms as it can mimic other small round blue cell tumors.
Mixed Adenoneuroendocrine Carcinoma: Is It a Collision Tumor or a Dedifferentiated Carcinoma?
Authors: Nazir Bushra , Ross Howard , Mittal Juhi , Taraif Suad 
Published: September 2019

Abstract
Mixed adenoneuroendocrine carcinoma (MANEC) of the gastrointestinal tract is uncommon with about 100 cases reported involving esophagus, stomach, colon, rectum, and biliary tree. The aggressive behavior of these tumors is usually dictated by the high-grade neuroendocrine carcinoma (NEC) component, which raises the possibility that these may represent areas of dedifferentiation. We here report an 88-year-old male presenting with rectal bleeding. Colonoscopy identified a fungating, villous, and partially circumferential cecal mass. Biopsy revealed tubular adenoma with focal high-grade dysplasia. However, excision was recommended given the impression of a mass. A right hemicolectomy revealed an 8.7-cm friable and ulcerated mass in the cecum. Initially, eight sections (one per cm) of the tumor were examined and revealed intramucosal adenocarcinoma. However, one of the lymph nodes was replaced by a high-grade poorly differentiated tumor, immunophenotypically consistent with NEC. In search for a primary, the rest of the mass was submitted and subsequent histologic examination revealed areas of transition from villous adenoma to intramucosal and muscle invasive adenocarcinoma in addition to deeply invasive NEC showing marked cytological atypia, brisk mitotic activity (Ki-67 >90%), and lymphovascular invasion. Three lymph nodes had metastatic adenocarcinoma and NEC along with several tumor deposits. Following an uneventful postoperative course, the patient received adjuvant chemotherapy. Our case recapitulates the classic description of MANEC where NEC is usually associated with a differentiated adenocarcinoma, commonly arising from an adenoma. The currently proposed pathogenesis is a collision tumor (previously known as mixed exocrine/endocrine carcinomas). However, we propose viewing MANEC as one tumor rather than two colliding tumors utilizing the concept of dedifferentiation, which has been extensively studied in the GYN literature. In a prior study, we found neuroendocrine expression in 41% of undifferentiated endometrial carcinomas. We therefore propose revisiting larger case series of MANEC with this concept in mind.
Signet Ring Cell Carcinoma of the Extrahepatic Bile Duct: A Case Report
Authors: Hameed Nadia , Marbut Stephen 
Published: September 2019

Abstract

Introduction
Signet ring cell carcinoma (SRCC) of the biliary system is extremely rare and its clinicopathological features and impact on prognosis are not well known. We report the extremely rare case of SRCC originating from the extrahepatic bile duct.

Case Report
We present a 76-year-old female who had elevated liver enzymes noted on routine laboratory test. Abdominal imaging revealed a polypoid mass within the central bile duct, located above the level of pancreatic head with proximal intrahepatic duct dilatation with no significant lymphadenopathy or ascites. Total bilirubin was normal, alanine transaminase level was 163 IU/L, and aspartate aminotransferase was 55 IU/L. The patient underwent common bile duct excision with cholecystectomy. The specimen showed a 3.3-cm centrally located tan polypoid lesion in the common bile duct with adjacent firm lymph node. Microscopic examination of the lesion revealed sheets of tumors cells with signet ring cell morphology underlying benign biliary epithelium. The lymph node was completely replaced by neoplastic cells. The neoplastic cells were diffusely positive for CDX2 and focally positive for CK7 and CK20. The histomorphology and immunophenotype are consistent with poorly differentiated adenocarcinoma with signet ring cell type.

Conclusion
SRCC of the extrahepatic bile duct is a histologically distinct entity classified by the World Health Organization, but it is very rare. To best of our knowledge, only five cases of SRCC of the extrahepatic bile duct have been reported in the English literature.
A Case of Immune-Mediated Necrotizing Myopathy With Associated Skeletal Muscle Involvement by Sarcoid Granulomata: A Rare Association
Authors: Akbar Shalla , Dasaraju Sandhya , Elkadi Osama 
Published: September 2019

Abstract

Skeletal muscle involvement by noncaseating granulomata occurs in a variety of conditions, including sarcoidosis, infections, and rarely in association with primary inflammatory myopathies such as inclusion body myositis (IBM) and dermatomyositis (DM). Sarcoid myopathy is typically asymptomatic; however, a picture of acute myositis with proximal muscle weakness has been described. Immune-mediated necrotizing myopathy (IMNM) is a subgroup of inflammatory myopathies typically presenting with proximal muscle weakness and markedly elevated muscle enzymes, mostly occurring in the setting of statin treatment. IMNM is associated with positive autoantibodies, but a subset of cases is antibody negative. Here we describe a case of myopathy occurring in association with sarcoidosis with combined features of granulomatous and necrotizing myopathy.
The patient was a 54-year-old African American male with medical history significant for statin use 3 years ago, which was discontinued due to myalgia and elevated muscle enzymes and biopsy-proven sarcoidosis diagnosed on a pulmonary lymph node biopsy. He presented with progressive worsening of bilateral proximal weakness involving the upper and lower extremities. Electromyogram showed features of active myopathy with no evidence of peripheral neuropathy. Myositis panel was negative for the following antibodies: anti-Jo1, Mi-2, anti-Ku, PL-7, PL-12, OJ, EJ, and SRP. However, there was elevation of aldolase, CRP, and CK-MB. Biopsy of thigh and deltoid muscle showed necrotic muscle fibers, myophagocytosis with associated minimal inflammation, and multiple well-formed nonnecrotizing granulomas with multinucleated giant cells. Myopathic features include increased internalized nuclei, round atrophic fibers, and scattered split fibers. Specific features of IBM or DM were not present.

Conclusion
Myopathies developing or worsening after discontinuation of statin are rare. The association of necrotizing myopathy with sarcoidosis is not well described in the literature. Additional studies are warranted to elucidate this association.