Intratumor heterogeneity of morphometric and stereologic variables in primary ovarian tumors and their omental metastatic deposits

OBJECTIVE: To compare quantitative pathologic variables assessed in primary ovarian tumors and metastatic tumor deposits in the omentum and compare their prognostic value. STUDY DESIGN: In 29 cases of advanced ovarian cancer the mean nuclear area (MNA), volume-weighted mean nuclear volume (v̄(v)), volume percentage epithelium (VPE) and mitotic activity index (MAD were assessed in both the primary ovarian tumor and its metastatic deposits in the omentum. Differences were evaluated using the Wilcoxon rank sum test for paired observations, and coefficients of variation were calculated in each case over the values obtained from the tumor in the ovary and omentum. RESULTS: Intraobserver and interobserver reproducibility of MNA, VPE and MAI were all good to very good except for the interobserver reproducibility for (v̄(v)), which was moderate. MNA and (v̄(v)), correlated well, both in the primary ovarian tumor (r=.88) and omental metastasis (r=.87). No significant differences were found between the assessments of MNA, (v̄(v)), and MAI in the primary ovarian tumor and its omental metastasis, whereas significant differences were found for VPE. However, in some patients the nuclei tended to be larger and the VPE lower in the omental metastasis than in the primary ovarian tumor. No important impact of the origin of tumor tissue was reflected in the prognostic value of the nuclear features. Patients were grouped prognostically differently for the assessment of MAI and VPE in the primary ovarian tumor and its omental metastasis. CONCLUSION: Quantitative pathologic variables for prognostic purposes are best assessed in the primary ovarian tumor. Measurements in the metastatic deposits may be helpful in understanding processes of metastasis in advanced ovarian cancer.