Survival between synchronous and non-synchronous multiple primary cutaneous melanomas-a SEER database analysis

Jie Xiong; Yanlin Su; Zhitong Bing; Bihai Zhao

doi:10.7717/peerj.8316

Survival between synchronous and non-synchronous multiple primary cutaneous melanomas-a SEER database analysis

PeerJ. 2020 Jan 3:8:e8316. doi: 10.7717/peerj.8316. eCollection 2020.

Authors

Jie Xiong^{1

2}, Yanlin Su³, Zhitong Bing⁴, Bihai Zhao¹

Affiliations

¹ Department of Mathematics and Computer Science, Changsha University, Changsha, Hunan, China.
² Department of Epidemiology and Health Statistics, Central South University, Changsha, Hunan, China.
³ Department of Gynaecology and Obstetrics, Changsha Central Hospital, Changsha, Hunan, China.
⁴ Evidence Based Medicine Center, Lanzhou University, Lanzhou, Gansu, China.

Abstract

Background: There is no criterion to distinguish synchronous and non-synchronous multiple primary cutaneous melanomas (MPMs). This study aimed to distinguish synchronous and non-synchronous MPMs and compare the survivals of them using the Surveillance, Epidemiology, and End Results database.

Methods: Synchronous and non-synchronous MPMs were distinguished by fitting the double log transformed distribution of the time interval between the first and second primary cutaneous melanomas (TIFtS) through a piecewise linear regression. The overall and melanoma-specific survivals were compared by the Kaplan-Meier method and Cox proportional hazard model through modeling the occurrence of synchronous MPMs as a time-dependent variable.

Results: The distribution of TIFtS was composed by three power-law distributions. According to its first inflection point, synchronous MPMs were defined as tumors that occurred within 2 months. The Kaplain-Meier plot revealed a significant inferior survival for synchronous MPMs than non-synchronous MPMs (P < 0.0001), and the occurrence of synchronous MPM was a risk factor for overall survival of cutaneous melanoma (CM) (hazard ratio: 2.213; (95% CI [2.087-2.346]); P < 0.0001).

Conclusions: This study provided data analysis evidences for using 2 months to distinguish synchronous MPMs and non-synchronous MPMs. Furthermore, the occurrence of synchronous MPM was a risk factor for prognosis of patients with CM.

Keywords: Multiple primary cutaneous melanoma (MPM); Non-synchronous; Surveillance epidemilogy and end results (SEER); Survival; Synchronous.

Grants and funding

This work is supported by the National Natural Science Foundation of China (61772089, 61873221, 61672447), Natural Science Foundation of Hunan Province (2019JJ40325, 2018JJ3566, 2018JJ3565, 2018JJ4058, 2017JJ5036), Scientific Research Fund of Hunan Provincial Education Department (19A043, 19C0177, 19C0181), and Research Project of Hunan Provincial Health Commission (20201952, 20201903).