Prevalence of precursor lesions (P53 signature, SCOUT, STIL, STIC) in fallopian tubes resected for non-neoplastic causes

ABSTRACT

Background: High-grade pelvic serous carcinoma is a common cause of death in women worldwide and India. Recent evidence has clearly implicated the changes in the mucosa of the fimbrial end of the fallopian tube in its pathogenesis. Objective: 1) To study histopathology features of surgically resected specimens of fallopian tubes received with non-neoplastic lesions of the uterus and ovary for the presence of any precursor lesions [secretory cell outgrowth (SCOUT), serous tubal intraepithelial lesion (STIL), p53 signatures, and serous tubal intraepithelial carcinoma (STIC)]. 2) To confirm the findings with immunohistochemistry. 3) To correlate the prevalence of precursor lesions with clinical parameters and benign lesions of the uterus and ovaries. Materials and Methods: Assessment of histopathological changes in 100 specimens of distal fallopian tubes was done using the sectioning and extensive examination of the fimbrial end (SEE-FIM) protocol. H and E stain followed by immunohistochemistry for Bcl-2, p53, and Ki-67. The statistical significance of the difference in the mean values of precursor areas was evaluated by an unpaired t-test. Results: Among 100 specimens taken on H and E, precursor lesions were suspected in 49% of the cases. SCOUT, suspicious for STIC, suspicious for STIC with areas of SCOUT, and unequivocal for STIC with areas of SCOUT were seen in 8%, 4%, 33%, and 4% of the cases, respectively. However, on IHC, SCOUTS were confirmed in 45% of the cases, p53 signature in 2%, STIL in 9%, and STIC in 4% of the cases. Conclusion: Sectioning and extensive examination of the fimbrial end (SEE-FIM) should be routinely done as it provides the opportunity to detect the early malignant changes. It may help in evolving the strategies for early detection, management, and reducing mortality.