Intraoperative squash cytology and histology of giant cell ependymoma: A diagnostic dilemma.

Giant cell ependymomas (GCE) are extremely rare tumors, with 24 cases described in the literature. Squash cytology is a rapid, reliable, simple technique for intraoperative consultation in neurosurgical practice. We describe a rare case of GCE arising at level of L4-L5 in a 66-year-old woman and discuss the cytologic/histologic features. Intraoperative smears were highly cellular with a prominent fibrillary background and exhibited papillary structures and sheets composed of highly atypical and bizarre cells. Some of the cells showed nuclear pseudoinclusions and rarely formed pseudorosette-like arrays. Intraoperative diagnosis was high grade glial tumor. On paraffin sections, besides extensive polymorphism, there were no microvascular proliferation, necrosis, and mitosis and the final diagnosis was WHO grade II GCE. GCE may be a diagnostic challenge on intraoperative smears, frozen, and paraffin sections. It must be kept in mind in the differential diagnosis of giant cell exhibiting benign and malignant tumors of brain.

Does single receptor positive breast carcinoma differ with regard to age, tumor grade, and HER2 amplification status?

PURPOSE: To investigate whether there is a difference in patient and tumor characteristics in cases with single receptor positive (SRP) (ER-/PR+ and ER+/PR-) breast carcinoma in comparison with the double receptor positive (DRP) (ER+/PR+) and double receptor negative (DRN) (ER-/PR-) tumors. METHODS: A total of 255 breast cancer patients were categorized on the basis of their tumor hormonal receptor phenotype, age, grade, and HER2 amplification status. The study focused on the SRP phenotype (ER+/PR- and ER-/PR+) and compared it with the DRP (ER+/PR+rpar; and DRN (ER-/PR-) tumors. RESULTS: There were 103 (40.3%) DRP tumors, 98 (38.4%) DRN tumors and 54 (21%) SRP tumors, 41 (16.1%) of which were ER+/PR- and 13 (5.1%) were ER-/PR+. Compared to DRP tumors, the SRP group was more likely to be associated with grade 3 tumors and higher frequency of HER2 amplification status. ER-/PR+ tumors were more likely to be associated with younger age at diagnosis compared to ER+/PR- tumors. HER2 amplification, age, and grade were not significantly different between ER-/PR+ and DRN groups. Compared to the DRN group, the ER+/PR- group had lower grade. CONCLUSIONS: Our findings demonstrated that SRP phenotype including ER+/PR- and ER-/PR+ tumors is different from DRP group with regard to age, grade, and HER2 amplification status. Moreover, our data showed that ER-/PR+ tumors are associated with younger age.

The Role of Parafibromin, Galectin-3, HBME-1, and Ki-67 in the Differential Diagnosis of Parathyroid Tumors.

OBJECTIVES: Parathyroid carcinoma (PC) is a rare parathyroid tumor compared to parathyroid adenoma (PA) and atypical parathyroid adenoma (APA). Recent studies have suggested parafibromin has a role in the differential diagnosis of parathyroid tumors. We sought to determine the role of parafibromin as well as galectin-3, Ki-67, and HBME-1 as diagnostic markers in the differential diagnosis of parathyroid tumors. METHODS: A total of 92 cases diagnosed with PA, APA, or PC at Sifa University and Private Ege Pathology Laboratory between 2006-2012 were included in the study. Parafibromin (microarray), galectin-3, Ki-67, and HBME-1 were evaluated using immunohistochemistry in all parathyroid tumors. RESULTS: Eighty-four cases were diagnosed with PA, six with APA, and two with PC. The study group consisted of 82 females and 10 males. Their mean age was 50.9 years, and the mean tumor diameter was 1.97 cm. Parafibromin was negative in the two PC cases but positive in all APA and PA cases. Positivity was observed with galectin-3 in 17 adenoma cases, three atypical adenomas, and two carcinoma cases. Positivity with HBME-1 was found in 26 PA cases and one PC case. Parafibromin and galectin-3 expression was significant between the three tumor groups but not for HBME-1 expression. Parafibromin expression increased in PA whereas galectin-3 expression decreased. A statistical significance was found between the three tumor groups according to the Ki-67 score (p=0.010). Additionally, the Ki-67 proliferation index was under 1% in PAs. CONCLUSION: The number of PCs in our series was small so our data mostly reflects the immunohistochemical characteristics of PAs. Parafibromin expression, galectin-3 negativity, and a Ki-67 proliferation index under 1% were estimated as beneficial in the differential diagnosis of difficult parathyroid tumors.