Significance of lymph node ratio in defining risk category in node-positive early stage cervical cancer

The ratio of positive to negative lymph nodes, or lymph node ratio (LNR), is an important prognostic factor in several solid tumors. The objective of this study was to determine if LNR can be used to define a high-risk category of patients with node-positive early stage cervical cancer.

We performed a retrospective review of patients diagnosed with node-positive stage I or II cervical cancer who underwent radical hysterectomy and pelvic +/- para-aortic lymphadenectomy at MD Anderson from January 1990 to December 2011. Univariate and multivariate analyses were used to identify prognostic factors for progression-free (PFS) and overall survival (OS).

Ninety-five patients met the inclusion criteria and were included in the analysis. Median total nodes removed were 19 (range 1-58), and median number of positive nodes was 1 (range 1-12). Fifty-eight patients (61%) received radiation with concurrent cisplatin and 27 patients (28%) received radiotherapy alone. Twenty-one (22%) patients recurred. On multivariate analysis, a LNR > 6.6% was associated with a worse PFS (HR = 2.97, 95% CI 1.26-7.02, p = 0.01), and a LNR > 7.6% with a worse OS (HR = 3.96, 95% CI 1.31-11.98, p = 0.01). On multivariate analysis, positive margins were associated with worse PFS (p = 0.001) and OS (p = 0.002), and adjuvant radiotherapy (p = 0.01) with improved OS.

LNR appears to be a useful tool to identify patients with worse prognosis in node-positive early stage cervical cancer. LNR may be used in addition to pathologic risk factors to tailor adjuvant treatment in this population.