PAX8-positive Biphasic Synovial Sarcoma Expressing Hormonal Receptors.

PAX8, estrogen receptor-α (ERα) and progesterone receptor (PR) are markers usually expressed in neoplasms of müllerian origin. We report a subdiaphragmal mass in a 41-year-old woman corresponding to a malignant biphasic tumor with nests of epithelial-like cells forming variably sized cyst-like spaces alternating with spindle cells forming intersecting fascicles. The later were juxtaposed to coalescent densely cellular nodules of spindle cells with appreciable cytologic atypia and mitotic counts up to 30/10 high-power fields. The tumor cells were AE1/AE3, EMA, ERG, ERα, PR, and PAX8 positive whereas spindle cells showed reduced immunopositivity for these markers, especially marked in coalescent nodular areas, with notable exception of PAX8, which was diffuse and strongly positive. The possibility of an endometrioid carcinoma with spindle cells was considered by the referring pathologist, but fluorescent in situ hybridization showed rearrangement of SS18 gene in 48 of 50 tumor nuclei, rendering a diagnosis of biphasic synovial sarcoma, the first reported in the English literature to the best of our knowledge expressing PAX8, ERα, and PR. Further studies evaluating the expression of these markers in synovial sarcoma and other sarcomas are needed, as sometimes the findings may lead to misdiagnosis as other neoplasms including those of the female genital tract. Additional molecular tests may be helpful to determine the molecular mechanism of this aberrant immunoprofile, which could be directly or indirectly related to t(X:18).

Vimentin and leukocyte common antigen-negative molding cells in pleural effusions of patients with small cell lung carcinoma.

OBJECTIVE: To determine whether the presence of vimentin and leukocyte common antigen (LCA)-negative molding cells (VLNMC) could help in identifying rare small cell lung carcinoma (SCLC) cells. STUDY DESIGN: Thirty-four cell blocks of pleural effusions (PEs) from 26 patients with confirmed SCLC were stained immunohistochemically with vimentin and LCA antibodies and compared with hematoxylin and eosin-stained preparations. RESULTS: VLNMC were present in 22/22 PEs originally diagnosed as positive or atypical/suspicious for SCLC. Focal vimentin staining was seen in SCLC in 10/22 cases, and 1 case showed many vimentin-positive SCLC cells. One of 11 PEs originally interpreted as negative showed rare groups of VLNMC. This was supported by a subsequent PE obviously positive for SCLC. CONCLUSION: Immunoperoxidase stains for vimentin and LCA highlight SCLC in PEs as VLNMC; however, morphologic criteria must prevail in making the final diagnosis.

Breast masses: removal of all US evidence during biopsy by using a handheld vacuum-assisted device--initial experience.

PURPOSE: To assess the effects of removal of all ultrasonographic (US) evidence of breast lesions by using a vacuum-assisted biopsy (VAB) device. MATERIALS AND METHODS: Thirty-four women with breast masses underwent US-guided biopsy with an 11-gauge VAB device, with which removal of all evidence of the lesion was attempted. Histologic findings were compared with results of surgery and follow-up imaging. Patient tolerance and perceptions of the procedure and the ability of the procedure to eliminate a palpable finding were evaluated with questionnaires and findings at follow-up physical examination. RESULTS: The biopsy protocol was completed in all cases. Twenty-six benign lesions (76%) and eight malignancies (24%) were diagnosed. After VAB, 10 patients (29%) underwent surgery on the basis of histologic findings of invasive carcinoma (n = 7), ductal carcinoma in situ (n = 1), lobular neoplasia (n = 1), or atypical ductal hyperplasia (n = 1). VAB resulted in complete excision of four of 10 lesions: two of eight malignancies and two of two benign lesions. Among 21 patients with benign lesions who underwent 6-month follow-up imaging, eight (38%) had a definite residual mass. At 6-month follow-up examination, VAB was seen to have eliminated the palpable abnormality in seven (88%) of eight patients with initially palpable benign masses. Thirty-two patients (94%) described no or mild pain during biopsy, and 33 patients (97%) rated care as excellent. CONCLUSION: After removal of all US evidence of breast masses with a VAB device, there was a substantial probability that residual lesion that was not visualized during the procedure would later be found at surgery or follow-up imaging. A palpable mass (< or =1.2 cm in mean diameter) was eliminated in 88% of cases, and patient tolerance and perceptions of the procedure were favorable.