Reza Parsaei - Department of Surgery, Tehran University of Medical Sciences, Tehran, Iran
Fezzeh Elyasinia - Department of Surgery, Tehran University of Medical Sciences, Tehran, Iran
Armita Aboutorabi - Kaviani Breast Disease Institute, Tehran, Iran
Fatemeh Saberi - Kaviani Breast Disease Institute, Tehran, Iran

Background: There is a hypothesis that the time of day can affect the outcomeof medical procedures and surgical operations. The current study was designed toassess whether time of day can influence the quality of breast cancer surgery or not.Methods: Patients who underwent breast cancer surgery and axillary lymphnode dissection in Tehran, Iran between March ۲۰۱۲ and March ۲۰۱۳ wereenrolled. Surgeries were categorized into two groups based on the time of initiation(before and after ۱ pm).We considered the number of dissected lymph node as anindicator of operation quality. In this way, dissection of at least six lymph nodeswas considered as an adequate number of lymph node examinations.Results:Atotal of ۱۳۴ patients were enrolled. Median start time of surgery was۱۱ am. Surgeries were performed before and after ۱ pm in ۱۰۵ (۷۸.۴%) and۲۹(۲۱.۶%) patients, respectively. The association between time and the number ofdissected lymph nodes was significant when they were considered either as acategorical (P= ۰.۰۰۲) or continuous variables (P= ۰.۰۳۹).Conclusions: Based on our results, it can be suggested that breast surgerieswith later start time might have lower quality.

Quality, time of day, breast surgery, axillary dissection