Introduction/Background The status of the surgical margins of lumpectomy specimens is one of the most important determinants of local recurrence during breast cancer management.

The usefulness of practicing systematic cavity shaving is still subject to debate but could avoid surgical re-excision and allow diagnosis of multifocality.

Methodology This is a retrospective, analytical, single-center study carried out in the Gynecology and Obstetrics department at Charles Nicolle University Hospital in Tunis, Tunisia, over a period of 5 years between January 2016 and December 2020, including patients who had conservative treatment associated with systematic cavity shaving as part of the management of breast cancer.

Results We included 93 patients. The median age was 48 years with extremes ranging from 25 to 95 years.

The median radiological tumor size was 22 mm with extremes of 9 to 40 mm.

The volume of the lumpectomy specimen had a median of 134.5 cm3 (from 9 to 660 cm3).

A positive shave was noted in 20 patients (21.5%).

Among patients with tumor-free lumpectomy margins, 4 had a positive shave (4.3%).

Cavity shaving avoided the need for re-excision in 10.8% of cases and contributed to the diagnosis of multifocality in 4.3% of cases.

There was no correlation between the volume resected and the usefulness of the shaving.

In the multivariate study, we did not find any predictive factors of positivity or usefulness of the shaving.

Conclusion In our study, a useful cavity shaving rate of 10.8% allows us to recommend this procedure: for one out of 10 patients, it avoids surgical re-excision.

And since there is no specific population for whom shaving is most useful, we recommend practicing it systematically.

Disclosures Authors have no conflict of interest to declare.