94 RESULTS Nine of twelve smears (75%) were originally diagnosed as positive for carcinoma: eight were diagnosed as positive for adenocarcinoma and one was diagnosed as positive for inva- sive squamous cell carcinoma. In the cytological review diag- nosis, this case was confirmed as positive for adenocarcinoma as well as invasive squamous cell carcinoma. Three (25%) of the twelve smears were originally diagnosed as negative and Table 1. Cytologic features in cervicovaginal smears for uterine papillary serous carcinoma (n=9) Cytologic Features Cellularity Low Moderate High Smear background Acute inflammation Necrosis Blood Psammoma-body like structure Arrangement of tumor cells Papillary clusters Single cells Bare nuclei Flat sheets Tumor cells Nuclear size ( m) Dense cytoplasm Phagocytosis of neutrophils Cytoplasmic vacuole No. of cases (%) 4 (44.4) 3 (33.3) 2 (22.2) 8 (88.9) 5 (55.6) 4 (44.4) 1 (11.1) 8 (88.9) 6 (66.7) 5 (55.6) 2 (22.2) 10.0-20.0 8 (88.9) 3 (33.3) 2 (22.2) J.-Y. Park, H.S. Kim, S.R. Hong, et al. one case revealed a few atypical cells on a cytological review diagnosis. The nine positive samples form the basis of the description of the cytologic features of UPSC (Table 1). Smears showing malignant cells were distributed into three classifications of cellular smears: two smears were classified as highly cellular, three smears were classified as moderately cellular and four smears revealed a low cellular distribution. Cells were arranged in cellular aggregates, tight ball-like or short papillary clusters and on rare occasions, in flat sheets (Fig. 1). The malignant cells had large nuclei; they were at least two to four times the size of an intermediate cell nucleus. The nuclei were somewhat peripherally displaced and revealed irregular nuclear margins and generally finely clumped chro- matin with prominent nucleoli (Fig. 2). Although most tu- mor cells revealed prominent nucleoli, macronucleoli were inconsistently present in the cervical smears rather than those of histologic sections. The cytoplasm was basophilic, with small vacuoles and indistinct borders. Phagocytosis by neu- trophils was found to be less common (in 3 of the 9 cases). Malignant cells predominantly appeared as single cells or bare nuclei in the majority of cases. About 40-50% of the smears contained lysed blood and revealed tumor diathesis (Fig. 3). However, three smears revealed relatively clean backgrounds except for the presence of acute inflammation. Moderate acute inflammation was present in most samples. A few spheroid acellular structures suggestive of psammoma bodies were found in only one smear. Definite laminar concentrations were not found. One smear, which was originally diagnosed as an invasive squamous cell carcinoma, contained cells with a mar- kedly increased nuclear to cytoplasmic ratio and overlapping, Fig. 1. Cervical smear of uterine papillary carcinoma shows pap- illary fragment of tumor cells with irregular outline and acute inflam- matory cells in background (Papanicolaou stain, ×400). Fig. 2. Tumor cells of uterine papillary serous carcinoma have large nuclei with irregularly distributed chromatin, distinct nucleoli, irreg- ular nuclear margins and indistinct cytoplasmic borders (Papani- colaou stain, ×1,000).