No abstract

Objective: The molecular basis of prostate cancer is highly heterogeneous. Our study aimed to perform the mutation analysis of KRAS, BRAF, PIK3CA, and immunohistochemical (IHC) evaluation of EGFR, HER2, p16, and PTEN to demonstrate new areas for targeted therapies. Methods: A total of 24 prostatectomy samples diagnosed with adenocarcinoma were analyzed by microarray hybridization. Also, these samples were IHC stained for EGFR, HER2, P16, and PTEN. The cases were divided into two groups based on low and high Gleason scores. All findings were compared with the clinicopathological parameters of the patients. Results: While KRAS mutation was in 3/24 (12.5%) of our cases, BRAF and PIK3CA mutations were not detected. There was no significant difference between the groups in terms of KRAS mutation frequency. HER2 was immunohistochemically negative in all samples. There was no correlation between EGFR, P16 immunopositivity, and clinicopathological features. Conclusion: KRAS mutation frequency is similar to those in Asian populations. BRAF and PIK3CA mutation frequencies have been reported in the literature in the range of 0-15% and 0-10.4%, respectively, consistent with our study findings. HER2 immunoexpression is a controversial issue in the literature. EGFR and p16 expressions may not correlate with the stage.

Basal cell carcinoma (BCC) is the most common malignant tumor in humans. It can be seen anywhere in the skin, although more than 80% occurs in areas exposed to the sun, such as the head and neck. Chronic exposure to sunlight is thought to be the main etiological factor. Although the risk of metastasis in BCC is very low, the tumor may be locally aggressive and cause tissue destruction. We present three cases of BCC in atypical locations, the waist region, the lateral femoral region, and the perineal region. No predisposing factor in terms of etiology of BCC was encountered in these patients' histories. We are presenting our cases, together with a discussion of the current literature, to emphasize that BCC should be considered even in atypically located lesions.