Tumor progression, histologic grading and DNA-ploidy as predictive factors of lymphogenous metastasis in primary carcinoma of the Fallopian tube

Abstract

The bad prognosis of primary carcinoma of the Fallopian tube (FTC), with 5-year overall survival rates of only 35%, is particularly ascribed to lymphogenous metastasis. Yet, we know very little on the pathophysiologic factors on which this lymphogenous metastasis is based. The present study, therefore, aims at evaluating the influence of intra-abdominal tumor progression and tumor-cell anaplasia on lymphogenous metastasis in FTC. We studied 41 cases of FTC, who had been subjected to radical lymphadenectomy during primary operation in a retrospective analysis. Staging was done by International Federation of Gynecology and Obstetrics-classification. Histologic grading and nuclear DNA-content (DNA-index) were used for evaluating tumor-cell anaplasia. Histologic grading discriminated between highly differentiated (G1), moderately dedifferentiated (G2), and dedifferentiated (G3) tumors. According to their DNA-indices, tumors were separated into three groups: DNA-index ≤1.1 (euploid cases), DNA-indices between 1.1 and 2.0 (cases of intermediate ploidy), and DNA-index >2.0 (aneuploid cases). The overall incidence of lymph node metastases was 43.9%. There was no correlation between histologic grading and DNA-index ( P=0.98). Lymphogenous metastasis set in after the tumor had transgressed the tube (intra-abdominal stage II). Further intra-abdominal tumor progression (including omentum, liver, or peritoneum) significantly increases the incidence of lymph node metastases ( P=0.02). There was only a single G1-tumor that had already disseminated into the lymph, all other cases of lymph node metastases were found in G2- or G3-tumors. DNA-index and the extent of lymphogenous metastases were not found to be correlated ( P=0.74). Conclusions: The extent of lymphogenous metastases in FTC depends above all on intra-abdominal tumor progression. This fact has clinical consequences as the indication for lymphadenectomy can be obtained directly during operation. The results of histologic grading are of no impact on the surgical proceedings; the determination of DNA-ploidy is negligible.