Tip-137;
High-grade serous carcinoma; HGSC, is a high-grade epithelial neoplasm demonstrating serous differentiation originating in the fallopian tube. The non-invasive form is called serous tubal intraepithelial carcinoma; STIC. Precursor lesions with less atypia are termed serous tubal intraepithelial lesions; STILs. The occurrence rate of STIC in fallopian tubes from prophylactic salpingo-oophorectomy is as high as 5-10% in the high-risk population like BRCA carriers, where about 40% are seen in association with invasive pelvic HGSC, and in less than 1% in the general population. A reported 16-43% of cases have been associated with germline BRCA mutations. There is evidence for lineage continuity between STIC and STIL in disseminated HGSC.
STIL is defined as pseudostratified growth of columnar cells with increased N: C ratio, mild nuclear pleomorphism, and preserved cell polarity. STIC is defined as lesions with abnormal morphological features including high N:C ratio, nuclear enlargement, pleomorphism, hyperchromasia, lack of ciliated cells, loss of polarity with or without epithelial stratification, and occasional mitotic figures, along with aberrant p53 expression defined as 75%, strong or moderate to complete absence known as the null staining pattern, and increased Ki-67 immunostaining more than 10%.
Isolated STIC shows subsequent development of HGSC in 4.5% of patients.
Remember that the presence of STIC or any mucosal HGSC or obliteration of part or all of a tube by the tumor mass signifies a primary tubal lesion.
28 сен 2024
