Region-specific Risk Factors for Pelvic Lymph Node Metastasis in Patients with Stage IB1 Cervical Cancer

Area of Science:

• Gynecology
• Oncology
• Pathology

Background:

• Pelvic lymph node metastasis (LNM) is a critical prognostic factor in cervical cancer.
• Identifying specific risk factors for LNM in different pelvic regions is essential for tailored treatment strategies.

Purpose of the Study:

• To identify region-specific risk factors for pelvic lymph node metastasis (LNM) in patients with stage IB1 cervical cancer.
• To develop and validate a predictive nomogram for LNM based on preoperatively assessable factors.

Main Methods:

• Retrospective analysis of 728 patients with stage IB1 cervical cancer undergoing radical hysterectomy and pelvic lymphadenectomy.
• Multivariate logistic regression to evaluate risk factors for LNM in specific pelvic regions (obturator, internal iliac, external iliac, common iliac).
• Nomogram development and validation in an external cohort (N=242), assessing calibration and discrimination.

Main Results:

• Lymph node metastasis (LNM) was detected in 14.6% of patients, with varying incidences across pelvic regions.
• Tumor size (<2 cm) and lymph-vascular space invasion (LVSI) were independent risk factors for common iliac and lower pelvic LNM, respectively.
• Older age (>50 years) was an additional risk factor for obturator LNM. The developed nomogram demonstrated good predictive performance.

Conclusions:

• Tumor size, LVSI, and age are significant, region-specific risk factors for pelvic LNM in stage IB1 cervical cancer.
• These factors can inform the appropriate extent of pelvic lymphadenectomy, potentially optimizing surgical management.
• The validated nomogram offers a valuable tool for predicting LNM risk and guiding clinical decisions.