Identifying factors contributing to reduced breast tumor size: a longitudinal study.

Aim: This study examines the trends and outcomes of breast cancer patients who have undergone surgical procedures at the Department of Surgical Sciences, University of Insubria, Varese, Italy. It also identifies the factors that contributed to the reduction of the breast tumor size over a 13-year period at a tertiary referral center.

Methods: All breast cancer operations performed at the Department of Surgical Sciences, University of Insubria, Varese, Italy, from January 1992 to June 2005 were examined and data from their surgical pathology reports were also analyzed, using a prospective database. A longitudinal study was performed to compare and analyze the pathological data during three consecutive time periods. The periods were from 1992 to 1996, 1997 to 1999, and 2000 to 2005. Surgical and pathological outcomes included age of the patient at the time of the diagnosis, partial breast resections, mastectomies, axillary lymphadenectomies, tumor size, histological type and stage, and lymph node status.

Results: The study group was comprised of 3050 patients who underwent breast resection between 1992 and 2005. Quadrantectomy was the preferred surgical approach in 1759 patients (58%). Throughout the longitudinal study, the tumors measuring less than 1cm increased from 13.4% to 15.4%; the number of tumors diagnosed at stage I increased from 44.1% to 56.8%; the most frequent histological type was ductal carcinoma; the number of ductal carcinomas in situ (DCIS) increased from 4% to 6%; and the incidence of lymphadenectomies decreased from 71.6% to 52.5%. Perioperative factors that correlated with the decreased size of the tumor over time were: screening, improvement of diagnostic and therapeutic techniques, and the increased operative use of sentinel lymph node biopsy (SLNB).

Conclusions: There has been an evolving refinement in surgical technique and perioperative management of breast cancer patients undergoing surgical resection at the Department of Surgical Sciences, University of Insubria, Varese, Italy, during the past decades. The present longitudinal study on 3050 surgical breast cancer patients confirmed the progressive reduction of tumor size at the time of the diagnosis. Perioperative factors that correlated with the decreased tumor size over time were mammography screening, improvement of diagnostic and therapeutic techniques, and the use of SLNB. Furthermore, the study showed that the progressive reduced number of useless axillary lymphadenectomies was mainly due to the increased intraoperative use of axillary SLNB.