Grading Ovarian Serous Carcinoma Using a Two-Tier System

Abstract

In this study, we evaluate a two-tier system for grading ovarian serous carcinoma. This system is based primarily on the assessment of nuclear atypia with the mitotic rate used as a secondary feature. The study included 50 cases of low-grade ovarian serous carcinoma and 50 cases of high-grade ovarian serous carcinoma retrieved from the files of the Department of Pathology at the University of Texas M. D. Anderson Cancer Center from a 28-year period. Cases assigned to the low-grade category were characterized by the presence of mild to moderate nuclear atypia. As a secondary feature, they tended to show up to 12 mitoses per 10 high power fields (HPFs), whereas those in the high-grade category had marked nuclear atypia and as a secondary feature more than 12 mitoses per 10 HPFs. For comparison, the tumors were also graded using the Shimizu/Silverberg and the FIGO grading systems. Patients in the low-grade ovarian serous carcinoma group ranged in age from 19 to 75 years (mean 41.7 years) while patients in the high-grade ovarian serous carcinoma group ranged in age from 27 to 76 years (mean 55 years). All of the cases except one were advanced FIGO stage. Using the Shimizu/Silverberg system, the low-grade ovarian serous carcinoma cases were distributed as follows: grade 1, 47 cases; grade 2, 3 cases. Using the FIGO grading system, 35 cases were grade 1 and 15 cases were grade 2. Regarding the high-grade ovarian serous carcinoma group using the Shimizu/Silverberg system, 14 of the cases were grade 2 and 36 cases were grade 3. Using the FIGO grading system, 1 case was grade 1, 38 cases were grade 2, and 11 cases were grade 3. Most of the patients in both groups were treated with total abdominal hysterectomy and bilateral salpingo-oophorectomy and also received cisplatinum-based chemotherapy. On follow-up, 37 patients in the low-grade ovarian serous carcinoma group had died of disease at a median 4.2 years after diagnosis compared with 46 patients in the high-grade ovarian serous carcinoma group who died of disease at a median of 1.7 years. Eight patients in the low-grade ovarian serous carcinoma group and 4 patients in the high-grade ovarian serous carcinoma group were alive with disease at median follow-ups of 4.3 and 3.85 years, respectively. Four patients with low-grade serous carcinoma were alive without evidence of disease after a follow-up that ranged from 4.4 to 22.6 years (median 6.85 years), and one died of other causes 14 years after the diagnosis of her ovarian tumor. On multivariate analysis, residual tumor and tumor grade based on the M. D. Anderson two-tier system for grading ovarian serous carcinoma were found to be significant independent prognostic factors (P = 0.003 and 0.04, respectively). Of interest, 60% of the low-grade ovarian serous carcinomas in this study were associated with a serous neoplasm of low malignant potential, whereas this association was present in only 2% of the high-grade ovarian serous carcinomas. This finding could reflect a difference in the pathogenesis of ovarian serous carci...

Molecular typing of epithelial ovarian carcinomas using inflammatory markers

“…Tumors were classified into serous, clear cell, endometrioid, and mucinous types, and graded as low and high grade using The University of Texas M. D. Anderson Cancer Center criteria. 13 Cases were categorized as type I or type II based on histopathology review and Kurman models. 2 After evaluating each case, 2 tumor blocks from each case were selected, and tissue microarrays (TMAs) were prepared.…”

Data set for reporting of ovary, fallopian tube and primary peritoneal carcinoma: recommendations from the International Collaboration on Cancer Reporting (ICCR)

“…Improvements in the understanding of the natural history and molecular pathology of serous carcinoma have demonstrated that HGSC and low-grade serous carcinoma are different tumour types with a different underlying pathogenesis and associated with different molecular events and prognosis. [40][41][42][43] Serous carcinomas are now classified as low-grade or high-grade and this has been endorsed by WHO 2014, 30 with the recognition that these are two different tumour types rather than low-grade and high-grade variants of the same tumour type.…”

Grading ovarian serous carcinoma using a two tier system: Does it have prognostic significance?

“…[7,8] Malpicia et al, evaluated a two tier system based on well-defined morphologic features of nuclear atypia with the mitotic rate used as a secondary feature. [9,10] The IJBAR (2015) 6 (03) www.ssjournals.com two tier grading system was shown to be useful in predicting outcome and is also in line with current thinking on serous ovarian tumour pathogenesis. [8,11,12] This study was done to evaluate a two tier system for grading of ovarian serous carcinoma, as compared to the three tier system and to determine whether a predictive relationship exists between grade and survival.…”

“…The numerical values in the present study are in concordance with the study done by Malpicia with majority of high grade tumours being redistributed in grade 2 and grade 3 of Shimizu/Silverberg grading system and majority of the high grade cases showing a mitotic count of ≥12/10HPFs. [9] When survival was modelled using a proportional hazard model with the two grading system as predictors the p values for the two tier grading and Shimizu/Silverberg grading were p = IJBAR (2015) 6 (03) www.ssjournals.com 0.62 and p = 0.69 respectively, with neither grade having a significant predictive ability. This was not in concordance with the study by Malpiciain which, the pvalues for the two tier grading system and the Shimizu/Silverberg classification system were p= 0.02 and 0.24 respectively.…”

“…The mitotic index (number of mitoses per 10 HPFs) was evaluated in the most mitotically active area of epithelial component of the tumour. [9]For comparison, tumours were also graded using the system proposed by Shimizu/Silverberg and categorized as well, moderately and poorly differentiated. [ Table 2][ Figure 1,2] Clinical information was obtained in all cases from the Medical Records Department.…”