Purpose: To identify the optimal size threshold and to assess the prognostic significance of supradiaphragmatic lymph nodes at initial presentation of patients with high-grade serous ovarian cancer (HGSC).
Methods: This IRB-approved, HIPAA-compliant retrospective study included baseline pretreatment staging abdominal CTs of 88 women (mean age 62 years, SD 10.4, range 29-85) with FIGO stage III HGSC. Patients with stage IV disease were excluded due to worse prognosis and management guided by distant metastases. Two fellowship-trained radiologists independently reviewed abdominal CTs to record the presence of supradiaphragmatic nodes, abdominal lymphadenopathy, peritoneal carcinomatosis, and ovarian mass. Progression-free survival (PFS) and overall survival (OS) were recorded after median 79 months follow-up (IQR 58-115, range 13-144). The optimal short-axis size threshold for supradiaphragmatic lymphadenopathy was determined by correlating 3, 4, 5, 6, 7, and 10 mm thresholds with PFS and OS using Log-rank test. Prognostic significance of supradiaphragmatic lymphadenopathy was assessed using Cox proportional hazards models.
Results: There was good interobserver agreement for presence (κ = 0.65, 95%CI 0.51-0.79) and size (ICC = 0.77, 95%CI 0.66-0.86) of supradiaphragmatic nodes. 5 mm short-axis size threshold was associated with significantly shorter PFS (median 14 months, IQR 11-17 vs. 23 months, IQR 12-59; p = 0.02) and OS (median 44 months, IQR 27-69 vs. 65 months, IQR 45-96; p = 0.03). Total 38/88 (43%) patients had supradiaphragmatic lymphadenopathy. On Cox proportion hazards analysis, supradiaphragmatic lymphadenopathy was significantly associated with shorter PFS (p = 0.02; HR 1.81, 95%CI 1.11-2.96) and OS (p = 0.008; HR 2.11, 95%CI 1.21-3.65).
Conclusion: In patients with stage III HGSC, supradiaphragmatic lymphadenopathy is associated with shorter PFS and OS. Further studies would help determine its implications on staging, decision regarding neoadjuvant therapy, and surgical technique.
Keywords: CT; Ovarian cancer; Overall survival; Progression-free survival; Supradiaphragmatic lymphadenopathy.