To investigate a population-based survey of the prevalence of human papillomavirus (HPV) infection in South Korea, we performed Papanicolaou smears and tests for HPV DNA and anti-HPV antibody detection in 909 sexually active general women (age range; 20-74 years, median 44 years) who were randomly selected residents from S district of Busan City. The presence of DNA of 36 different HPV types was detected by means of a GP 5+/6+ primer-mediated PCR enzyme immunoassay in cervical exfoliated cells, and IgG antibodies against L1 virus-like particles (anti-VLPs) of 5 HPV types 16, 18, 31, 33, and 58 were tested by means of enzyme linked immunoassay. The incidence of cytologic abnormality was 5.2% in Pap smear. The positive rate of HPV DNA was 10.4%, high in young women younger than 35 years old and proportionally increased according to the cytologic grades. The most often found HPV type was HPV 70, followed by HPV 16 and 33, and high-risk HPV types were more frequent in women younger than 35 years old. The most common HPV type in abnormal cytologic smears was HPV 16, followed by HPV 58 and 66. Anti-VLPs was positive in 19.7% and the frequent anti-VLPs type was against HPV 18, followed by HPV 31 and 16. The concordance between the markers for each specific HPV type was noted in 10 women and HPV 16 was the most frequent one. The incidence of multiple HPV infection was 18.9% and that of multiple anti-VLPs antibodies was 31%. Among 103 self-reported virgins, 4.9% had anti-VLP antibodies.

It was reported that the main cause of intraepithelial neoplasm and squamous cell carcinoma of the uterine cervix is human papilloma virus infection, and that the expression of p16 is increased in cells infected by human papilloma virus. We performed an immunocytochemical staining for protein p16 in 17 cases of cervocovaginal smears initially diagnosed as atypical squamous cells of undetermined significance, to know whether the staining could help the differentiation of neoplastic cells from reactive atypical cells. Of 17 smears, 6 were diagnosed finally as high grade intraepithelial neoplasm or invasive squamous cell carcinoma by follow-up biopsy and smear, and 5 of the 6 were positive for p16. Three were diagnosed as koilocytosis, and one of them was weakly positive for p16. Eight were diagnosed as reactive atypical cells, and all of them were negative for p16. We thought that immunocytochemical staining of p16 in cervocovaginal smears could help the differentiation of neoplastic cells from reactive atypical cells.

We compared the diagnostic accuracy of liquid-based cervicovaginal cytology using $MonoPrep2^{TM}$ system (Monogen, Herndon, Virginia, USA), a manual system based on membrane filtration method, with conventional Pap smear. Study population included 92 patients visiting the gynecologic department under the suspicion of uterine cervical disease. In thirty of them, surgical biopsy was performed. $MonoPrep2^{TM}$ system provided well-preserved monolayer specimen with good nuclear morphology. However, about 19% of specimens were inadequate to interpret due to low cellularity. The detection rate of abnormal cells more than ASCUS (atypical squamous cells of unknown significance) was 23.9% and higher than 19.4 % of conventional Pap smear. Diagnostic concordance rate with conventional Pap smear was 81%, and severe discordance rate influencing on the management of patient was 7.6 %. Among these seven cases, $MonoPrep2^{TM}$ system was more diagnostic only in four. In comparison with histology, the sensitivity of diagnosis of $MonoPrep2^{TM}$ system was 78.9% and slightly higher than 73.5% of conventional Pap smear. However, the specificity was 81.1% and lower than 90.9% of Pap smear. In conclusion, $MonoPrep2^{TM}$ system provided diagnostic accuracies similar to the conventional Pap smear. The inexpertness of slide preparation and the low cellularity were considered to endow a limitation in more accurate evaluation.

To evaluate the quality of fine needle aspiration cytology diagnosis on malignant salivary gland neoplasms, cytologic findings were correlated with histologic diagnosis of 56 surgically removed malignant salivary gland tumors. Seven cases (12.5%) were insufficient, 23 cases (41.1%) were diagnosed as malignant, 17 (30.4%) cases were accurately diagnosed by histologic subtype, and 9 cases (16%) were diagnosed as benign. Five out of 9 false negative cases were misdiagnosed as pleomorphic adenomas. Except the cases with insufficient specimen, overall sensitivity was 81.6%, and the sensitivity varied according to the histologic subtype; 91% in salivary duct carcinoma, 100% in carcinoma ex pleomorphic adenoma, 50% in mucoepidermoid carcinoma, 63% in adenoid cystic carcinoma, and 50% in acinic cell carcinoma. The diagnostic accuracy differed among cytopathologists irrespective of periods after acquisition of board of pathologists. These results confirm that salivary gland neoplasm can be easily misdiagnosed in fine needle aspiration cytology and a great caution should be given in diagnosing the benign appearing salivary aspirates to avoid under-diagnosis of malignant neoplasm with low grade cytologic atypia.

It is important to recognize the pathognomonic cytologic findings of chordoma, because of overlapping cytologic features between chordoma, chondrshdosarcoma, myxofilbrillary ependymoma, and metastatic adenocarcinoma. We reviewed the cytomorphologic features of 5 cases of chordoma diagnosed by fine needle aspiration cytology at Korean Cancer Center Hospital from 1987 to 2003. Clinical and radiographic findings of each case were reviewed. Four males and one female (29-54 years) had tumors involving the sacrum. Pain was the presenting symptom in 4 cases. The three cases showed moderate to high cellularity. In all cases, typical physaliferous cells with or without cytoplasmic processes were noted. In two cases, the background was myxoid with single scattered cells. Cell clusters showing cord-like arrangement were occasionally seen. The single or clustered cells showed mild cellular pleomorphism with slightly increased nuclear/cytoplasmic ratio. Mitotic figures were not seen. In our review, the recognition of physaliferous cells is the most important feature to diagnose chordoma and to differentiate it from other lesions mimicking chordoma.

Secretory meningioma is a distinct subtype of meningioma. We describe the cytologic features of a secretory meningioma on squash preparations, in comparision with other cytologic mimickers. A 54-year-old woman presented with hearing loss, vertigo, tinnitus, and headache for seven years. A brain MRI study revealed a 4.5cm sized mass in the cerebellopontine angle, which showed homogenous signal intensity in T2-weighted image. The intraoperative squash smear showed some well-defined, thin rimmed intracytoplasmic inclusions, containing a finely granular eosinophilic core among less cohesive meningiomatous cells. Histologic sections revealed a meningothelial meningioma with scattered inclusions, with periodic acid-Schiff, carcinoembryonic antigen, and cytokeratin positivity. Identification of characteristic intracytoplasmic inclusions is helpful for diagnosing secretory meningiomas. On squash preparations, differential diagnoses included tumors with inclusions or cytoplasmic vacuolizations, such as metastatic mammary infiltrating ductal carcinoma, gastric adenocarcinoma, hepatocellular carcinoma, and clear cell ependymoma, oligodendroglioma, hemangioblastoma, chordoma, and other variants of meningiomas (clear cell, xanthomatous, microcytic, and chordoid variants). In addition, the possibilities of glioma with eosinophilic granular body, and metastatic tumors from mammary infiltrating ductal carcinoma, gastric adenocarcinoma, and hepatocellular carcinoma in meningioma should be considered.

Development of an invasive squamous cell carcinoma within a branchial cleft cyst (branchiogenic carcinoma) is very rare and this case is the first description of cytologic findings in Korea. A 62-year-old man presented with a 5-month history of an enlarged right neck mass. Fine needle aspiration cytology of the mass showed low cellularity and the background containing proteinaceous debris, inflammatory cells, and histiocytes suggested a cystic nature. Abundant lymphocytes, a few anucleated squames, and rare atypical squamous cells with pyknotic nuclei and abnormal keratinization were also noted. After excision of the mass, histologic findings were consistent with a branchiogenic carcinoma. We recommend to raise the possibility of carcinoma (primary or metastatic) when we observe a few dyskeratotic cells in a cystic mass within the neck area, especially in an old male.

The macrofollicular variant of papillary thyroid carcinoma (MVPC) is characterized by macrofollicles occupying more than half of the tumor and demonstrating nuclear features of classic papillary carcinoma. It is difficult to recognize on fine needle aspiration (FNA) cytology due to the paucity of aspirated neoplastic cell clusters, especially when the tumor is associated with extensive areas of hemorrhage. Case: A 34-year-old female presented with a well-demarcated nodule in the thyroid gland, diagnosed as a benign nodule on ultrasonography and computed tomography. FNA cytology smear revealed a few small aggregates of follicular cells with morphological features suspicious for papillary carcinoma, set in a background of hemorrhage, inflammatory cells, and hemosiderin-laden macrophages. Intraoperative frozen section revealed macrofollicular nests filled with hemorrhage and composed of follicular cells demonstrating nuclear clearing and grooves. Conclusion: MVPC is a rare but distinctive variant of papillary carcinoma, which is easily mistaken for adenomatous goiter or benign macrofollicular neoplasm on radiologic findings. The cytopathologist should alert oneself on encountering benign radiologic findings and any smear composed of scant numbers of follicular cells with nuclear features suspicious for papillary carcinoma despite the bland-looking background of hemorrhage and hemosiderin-laden macrophages, and recommend intraoperative frozen sections for a definite diagnosis.

Epithelioid sarcoma is a malignant soft tissue neoplasm with an uncertain histogenesis. We report the imprint cytologic features of epithelioid sarcoma in the left shoulder of a 29-year-old male patient. Imprint cytologic findings showed dissociated and loose aggregates of anaplastic epithelioid cells on the necrotic, bloody, and inflammatory background. Tumor cells were round to polygonal shaped. Tumor cells had vesicular nuclei with abundant cytoplasm. The nuclei were irregular in shape and often eccentrically located. Some tumor cells were oval to spindle shaped. Binucleated and multinucleated cells were found. Intracytoplasmic vacuoles were present. On immunohistochemical stain, the tumor cells were positive for epithelial membrane antigen, vimentin, and CD34.

The incidence of endometriosis in post-operative abdominal scars is rare. We describe two cases of abdominal endometriosis diagnosed by fine needle aspiration (FNA). Both patients presented with subcutaneous masses at previous cesarean section scars with cyclic symptoms of pain. The cytologic smears were cellular and comprised two distinct cell populations consisting of epithelial and stromal components. An epithelial component consisted of flat sheets of polygonal cells and the second stromal component showed crowded clusters of spindle cells or isolated single cells. Hemosiderin-laden macrophages were found in the background. FNA offers a safe and effective tool for diagnosis of abdominal wall endometriosis.