It is well established that there is widespread variability in practice1,2 and that divergence from guidelines3,4,5,6 is common in the ordering of SS for pts with stage I/II EBC. This is influenced by multiple factors including pt preference. We therefore investigated the incidence and yield of SS in asymptomatic women by conducting a retrospective audit of consecutive Stage I/II EBC pts seen at Bankstown Cancer Centre between January 2014 – December 2016.
Our final cohort of stage I/II EBC pts was derived by cross-checking theatre, surgical audit and clinic lists via MOSAIQ (EMR) for the above time-period. Pts with symptoms were excluded. Data were collected for age, demographic information, histopathologic characteristics and conduct and yield of SS.
Our audit included 175 women with pre-operative Stage I/II EBC, asymptomatic for metastases. Median age was 64 (22 – 89). 76% (133) had invasive ductal carcinoma. 49% (86) were luminal A, 35% (61) were luminal B, 16% (28) were hormone insensitive- ie 11% (20) triple negative and 5% (8) were HER2 amplified. Pts who were both hormone sensitive and HER2 amplified comprised 9% (15). 73% (127) had staging CT chest, abdomen, pelvis while 76% (133) had technetium99m bone scans. 3% (4) had metastatic breast cancer (MBC) detected on SS. 13% (17) required further imaging +/-procedures due to incidental findings on SS.
75% of women in our audit underwent SS, of whom 3% had asymptomatic metastatic disease detected, while 13% of these women had incidental finding/s requiring further workup. Our results support the guidelines3,4,5,6 in avoiding SS in Stage I/II EBC in asymptomatic women due to low yield. Unfavourable biology did not predict for increased yield. Our results are consistent with existing literature regarding widespread variable SS ordering practices and divergence from guidelines1,2, for reasons other than stage.