Retrospective analysis of definitive radiotherapy for neck node metastasis from unknown primary tumor: Japanese Radiation Oncology Study Group study.

Abstract

OBJECTIVE:

To investigate the optimal treatment method and risk factor of neck node metastasis from unknown primary tumors (NUP) treated by radiotherapy.

METHODS:

Retrospective case study based on a multi-institutional survey was conducted by the Japanese Radiation Oncology Study Group. Patients pathologically diagnosed as having NUP from 1998 to 2007 were identified. Univariate and multivariate analyses of overall survival (OS), progression free survival (PFS), neck progression free survival (NPFS) and mucosal progression free survival (MPFS) were evaluated.

RESULTS:

In total, 130 patients with median age of 65 years were included. Nodal stages N1, N2a, N2b and N2c were observed for 10, 26, 43, 12 and 39 patients, respectively. All the patients received radiotherapy (RT) with neck dissection in 60 and with chemotherapy in 67 cases. The median doses to the metastatic nodes, prophylactic neck and prophylactic mucosal sites were 60.0, 50.4 and 50.4 Gy, respectively. The median follow-up period for surviving patients was 42 months. Among 12 patients, occult primary tumors in the neck region developed after radiotherapy. The 5-year OS, PFS, NPFS and MPFS were 58.1%, 42.4%, 47.3% and 54.9%, respectively. Univariate analysis showed that lower N stage (N1-2b), non-bulky node (<6 cm) and negative extracapsular extension (ECE) status were the factors associated with favorable OS, PFS, NPFS and MPFS. Radical surgery proved to be a favorable factor of OS, NPFS and MPFS. On multivariate analysis, lower N stage and negative ECE status were correlated with improved survival.

CONCLUSIONS:

Lower nodal stage and negative ECE status showed a favorable impact on survival and disease control in patients with NUP treated by radiotherapy.

• Authors: Takuya Yamazaki, Takeshi Kodaira, Yosuke Ota, Tetsuo Akimoto, Hitoshi Wada, Junichi Hiratsuka, Yasumasa Nishimura, Shunichi Ishihara, Takeshi Nonoshita, Kazushige Hayakawa, Shuhei Sekii, Nobue Uchida
• Journal: Japanese journal of clinical oncology (Jpn J Clin Oncol) Vol. 47 Issue 9 Pg. 856-862 (Sep 01 2017) ISSN: 1465-3621 [Electronic] England
• PMID: 28903529 (Publication Type: Journal Article)
• Copyright: © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: [email protected]

Topics

• Adult
• Aged
• Aged, 80 and over
• Disease-Free Survival
• Female
• Humans
• Japan
• Lymphatic Metastasis (radiotherapy)
• Male
• Middle Aged
• Neck (pathology)
• Neoplasms, Unknown Primary (pathology, radiotherapy)
• Retrospective Studies