Prognostic significance of lymph node metastasis and clear cell histology in ovarian carcinoma limited to the pelvis (pT1M0 and pT2M0)

Abstract

Background: The prognostic significance of lymph node (LN) metastasis in clinically early-stage (pT1M0 or pT2M0) ovarian carcinoma has not yet been fully elucidated.

Methods: From 1988 to 1997, 94 patients with ovarian carcinoma of pT1M0 (n = 78) or pT2M0 (n = 16) classification underwent surgery including systematic pelvic and paraaortic LN dissection. We investigated the prognostic factors of intraperitoneally determined early-stage ovarian carcinoma focusing on LN metastasis.

Results: LN metastasis was seen in 5.1% of pT1M0 and in 31.3% of pT2M0 tumors. Univariate analysis of grade, histology (clear cell vs others), size of primary tumor, peritoneal cytology, and LN metastasis revealed that histology (P < 0.01), size of tumor (P < 0.05), and LN metastasis (P < 0.0005) were related to patient survival of early-stage ovarian carcinoma. Peritoneal cytology (P = 0.053) and grade (P = 0.059) had marginal statistical significance. A multivariate Cox regression analysis showed that clear cell histology (P < 0.05) and LN metastasis (P < 0. 005) are significant independent prognosticators of patient survival. Three (two with clear cell adenocarcinoma and one with mucinous adenocarcinoma) of nine patients with LN metastasis had died of the disease by the time of the present analysis. Two of the three deceased patients had recurrent tumors in distant organs (bone and brain/liver), one had pleural and peritoneal carcinomatosis, and no patients had retroperitoneal recurrence. This suggests that LN metastasis indicates that tumor cells may have already spread systemically at the time of treatment and, at the same time, retroperitoneal lymph node dissection (RPLND) may be effective in eradicating retroperitoneal metastasis in some instances of ovarian carcinoma.

Conclusion: Clear cell histology and LN metastasis are indicators of poor prognosis for patients with tumors limited to the pelvis. Therapeutic significance of systematic RPLND for pT1M0/pT2M0 ovarian carcinomas needs to be further investigated by randomized studies.