The Clinicopathological Significance of Basal Markers in Early-Stage Invasive Carcinoma of No Special Type of the Breast.

OBJECTIVE: Basal markers [cytokeratin 5/6 (CK5/6) and epidermal growth factor receptor (EGFR)] are used in identifying the basal-like breast carcinoma subtype, which is associated with a poor prognosis. However, the clinicopathological significance in early-stage invasive carcinoma of no special type (IC, NST) has not been well established. MATERIAL AND METHOD: In a five-year period, 133 female patients with early-stage IC, NST with a median follow-up time of 89 months were included. The immunohistochemistry-based molecular subtypes were identified according to ASCO/CAP guidelines in 2013. The cutoff values for basal positivity were determined as 10% for each marker. RESULTS: Basal positivity was recorded in 83.3% (5/6) of triple-negative breast cancers, 50% (2/4) of HER2-enriched, 18.6% (13/70) of luminal B, and 8.3% of luminal A (4/48) subtype. CK5/6 and EGFR positivity were significantly associated with ER negativity (p < 0.001). EGFR positive cases were significantly associated with PR negativity and HER2 positivity compared to negative cases. However, basal positivity was not associated with the patient outcome (p = 0.006 and p = 0.004, respectively). CONCLUSION: Basal positive IC, NSTs were associated with hormone receptor negativity and HER2 overexpression; these patients would therefore be less likely to respond to hormonotherapy and more likely to benefit from anti-HER2 treatment as well as dual-kinase inhibitors. The lack of standardization of the definition of basal marker positivity may contribute to the conflicting results of prognostic studies. Hence, further studies focusing on developing a standard protocol for determining basal marker positivity are needed not only for IC, NST but also for other histological types of breast cancer.

Spindle Epithelial Tumor with Thymus-like Element (Settle): a Case Report.

Spindle epithelial tumor with thymus-like element (SETTLE) is a very rare malignant neoplasm of the thyroid. It is generally encountered in children, adolescents, and young adults Objective: We aimed to present a patient with SETTLE and to review the clinical and pathologic features of this rare tumor. A 13-year-old male patient presented to our clinic with complaints of a rapidly growing lump on his neck. There was no evidence of distant metastases at time of presentation. A total thyroidectomy was performed. Lymph node dissection was not performed. On the first postoperative day, the patient was discharged uneventfully. Histopathological and immunohistochemical analysis revealed a SETTLE in our case. During 1 year of follow-up, the patient had no complaints or symptoms, without tumor recurrence on imaging studies. Although SETTLE is a very rare entity, it should be considered when diagnosing rapidly growing masses in the thyroid, especially in younger patients.