Gender Differences in the Recurrence Timing of Patients Undergoing Resection for Non-Small Cell Lung Cancer

Document Type : Research Articles


1 Department of Surgery, Yokohama City University, Yokohama, Japan.

2 Department of General Thoracic Surgery, Yokohama Medical center, Yokohama, Japan.

3 Department of Biostatistics and Epidemiology, Yokohama City University, Yokohama, Japan.


Objective: This study was designed to visually represent postoperative recurrence patterns using event dynamics
and to assess sex-based differences in the timing of recurrence for non-small cell lung cancer. Methods: We studied
829 patients (538 men, 291 women) with NSCLC who underwent complete pulmonary resection in 9 hospitals. Event
dynamics with the use of life-table methods were evaluated, and only first events (distant metastases or local recurrence)
were considered. The effects of sex, histological type, pathological stage, and smoking history were studied. Result:
The resulting smoothed hazard rate curves indicated that the recurrence risk pattern definitely correlated with sex, with
a sharp peak in the first year in men and a broad peak during the first 2 to 3 years in women. These findings were also
confirmed by analyses according to pathological stage, histological type, and smoking history. Conclusion: The peak
times of recurrence differed considerably between men and women. The delayed time of peak recurrence in women,
associated with a longer disease-free interval within subsets of patients with similar disease stage, histological type,
and smoking status, might account for the better survival in women.


Main Subjects