J Cancer 2018; 9(16):2844-2851. doi:10.7150/jca.25505
Additional Cervical Lymph Node Biopsy is Not a Significant Prognostic Factor for Nasopharyngeal Carcinoma in the Intensity-Modulated Radiation Therapy Era: A Propensity Score-matched Analysis from an Epidemic Area
1. Department of Radiation Oncology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510060, Guangdong, P.R. China.
2. Department of Radiation Oncology, Sun Yat-sen University Cancer Center.
3. State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center.
4. Department of Radiation Oncology, Cancer Center, First People's Hospital of Foshan Affiliated to Sun Yat-sen University, Foshan, China.
5. The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
*These authors contributed equally to this work.
Yang XL, Wang Y, Bao Y, Liang SB, He SS, Chen DM, Chen HY, Lu LX, Chen Y. Additional Cervical Lymph Node Biopsy is Not a Significant Prognostic Factor for Nasopharyngeal Carcinoma in the Intensity-Modulated Radiation Therapy Era: A Propensity Score-matched Analysis from an Epidemic Area. J Cancer 2018; 9(16):2844-2851. doi:10.7150/jca.25505. Available from http://www.jcancer.org/v09p2844.htm
Introduction: This study aimed to evaluate the prognostic value of cervical lymph node biopsy and whether different biopsy methods would lead different outcomes in NPC in the intensity-modulated radiotherapy (IMRT) era.
Material and Methods: 1492 patients with biopsy-proven, non-metastatic NPC, and treated by IMRT with or without chemotherapy were retrospectively reviewed. Cervical lymph node biopsy was performed in 183 (12.3%) patients: 61(4.1%) by needle puncture and 118(7.9%) by excision biopsy. Propensity-score matching was used to match patients in both arms at an equal ratio. Overall survival (OS), distant metastasis-free survival (DMFS), locoregional relapse-free survival (LRFS), and nodal relapse-free survival (NRFS) were assessed using the Kaplan-Meier method and compared using the log-rank test. Independent prognostic factors were identified using the Cox proportional hazards model.
Results: In the original cohort of 1492 patients, patients receiving cervical lymph node biopsy had comparable survival (OS: P = 0.736, DMFS: P = 0.749, LRFS: P = 0.538, NRFS: P = 0.093,) with patients receiving isolated napharynx biopsy. The results for the propensity-match cohort of 316 patients were similar. Interestingly, compared with the control group and needle puncture biopsy group, a slightly lower nodal recurrence rate was observed in the excision biopsy group (P = 0.082 and P = 0.072, respectively). Adjusting for the known prognostic factors in multivariate analysis, cervical biopsy did not cause a higher risk of death, distant metastasis, or nodal relapse.
Conclusions: Pretreatment cervical lymph node biopsy is not associated with impaired survival in NPC, suggesting the resist of the biopsy and more aggressive treatment after the biopsy may be unnecessary.
Keywords: nasopharyngeal carcinoma, intensity-modulated radiotherapy, cervical lymph nodes biopsy, prognosis.