[1245] Morphological Effects of Chemotherapy on Ovarian Serous Adenocarcinoma

Iram Siddiqui, Michele Weir. London Health Sciences Center and University of Western Ontario, London, ON, Canada

Background: Ovarian serous carcinomas have traditionally been treated with surgical cytoreduction and post-operative chemotherapy with carboplatin/taxol. Recently, there is a growing tendency to treat advance ovarian cancers with neoadjuvant chemotherapy followed by debulking surgery. In these cases, the initial diagnosis is made on a biopsy, or cytological examination of the peritoneal fluid. The aim is to minimize tumour volume and obtain optimal cytoreduction. Treatment effects in such resections are reported, however, these chemotherapy induced effects on ovarian carcinomas have not been well studied. We sought to 1) assess chemotherapy changes in ovarian serous adenocarcinomas by comparing pre- and post-chemotherapy samples; and 2) examine grading post-chemotherapy.
Design: Archival cases of serous adenocarcinomas were reviewed, including: group a) pre-treatment biopsies (n=9); group b) subsequent post-chemotherapy resections of the same patients as in group a (n=9); and group c) resections without chemotherapy (n=18). We compared non-treated biopsies and resections (groups a and c) to post-chemotherapy resections (group b). Cases were evaluated for treatment effects (epithelial-stromal ratio, old hemorrhage, intratumoural lymphocytes, blood vessel proliferation, tumour necrosis, bizarre nuclei, giant cell reaction, foamy macrophages, ballooning and cholesterol clefts); treatment response (none, minimal or marked) and grading (Silverberg).
Results: The epithelial to stromal ratio was increased in all treated cases and correlated with the degree of treatment response (p=0.0005). Blood vessel proliferation (+2) and old hemorrhage and hemosiderin were significantly increased in all treated cases (p=0.0005 and p=0.015, respectively). Intra-tumoural lymphocytes (p=0.0001), bizarre nuclei, cholesterol clefts, giant cell reaction and foamy macrophages were nearly exclusively seen in treated cases. Four cases showed lobular carcinoma-like features. Post- compared to pre-chemotherapy grade remained the same or increased in 6/7 cases. Bizarre nuclei were a pitfall for nuclear atypia post-treatment.
Conclusions: Our study highlights specific morphological changes in serous adenocarcinomas treated with chemotherapy, which may be linked to treatment response. We identified three chemotherapy associated changes not reported previously, (epithelial to stromal ratio, blood vessel proliferation and intratumoural lymphocytes). Grading post-treatment was similar to pre-treatment (remains high grade 2 or 3).
Category: Gynecologic & Obstetrics

Monday, March 19, 2012 9:30 AM

Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 191, Monday Morning

 

Close Window