[Correlation between the primary tumor size of endometrial carcinoma and lymph node metastasis and recurrence]

Objective: To investigate the clinical significance of the primary tumor size in patients with endometrial carcinoma (EC). Methods: A total of 385 patients with EC admitted to Peking University People's Hospital from January 2006 to December 2016 with complete follow up data were selected, whose tumor size data before biopsy were retrospectively studied. Results: (1) The mean diameter of the primary tumor was (3.6±1.8) cm (range: 1-15 cm). And 48 cases were 0-<2 cm, 78 cases were 2-<3 cm, 92 cases were 3-<4 cm, 73 cases were 4-<5 cm, 94 cases were ≥5 cm. The diameter of the tumor was associated with age <60 years old, premenopause, CA₁₂₅≥35 kU/L, non-parturition, poor differentiation, stage Ⅲ-Ⅳ, depth of myometrial infiltration ≥1/2, cervical interstitial involvement, adnexal metastasis and lymph node metastasis (all P<0.05), but not associated with body mass index, hypertension, diabetes mellitus, pathology, lymph-vascular space invasion (all P>0.05). (2) Among the 334 patients underwent lymphadenectomy, 45 (13.5%, 45/334) cases with lymph node metastasis were observed. Stratified analysis showed that lymph node metastasis and recurrence rate of patients with EC gradually increased with the increase of tumor size (P<0.05). Adopting 2, 3, 4 and 5 cm as cut-off values of tumor size, there were significant differences in the rate of lymph node metastasis and recurrence among them observed (P<0.05), except for lymph node metastasis rate and recurrence rate when the cut-off value was 2 cm (P>0.05). (3) An receiver operating characteristic (ROC) curve analysis showed that a tumor diameter of 4.25 cm was the cut-off prognostic value to predict lymph node metastasis and recurrence of EC. Conclusions: Tumor diameter is significantly correlated with lymph node metastasis and recurrence in patients with EC. Tumor size should be considered in determining the scope of surgery and adjuvant therapy.