Role of primary tumour surgery in the management of oligometastatic breast cancer

Metastatic breast cancer has been long considered an incurable disease, however a subset coined oligometastatic breast cancer (OMBC) has challenged this assumption. OMBC represents a stable entity that presents as an intermediary state between locoregional and widespread disease where metastasised cells are limited to suitable sites potentially amenable to treatment. However, the treatment for OMBC is not standardised and a big limitation is diagnostic difficulty as it relies only on imaging findings. In the United Kingdom, a case by case discussion of treatment is made due to lack of guidance or framework. The role of primary surgical excision of the breast tumour in OMBC has been scrutinised with varying outcomes to date. This review evaluates the role of primary surgical excision and future directions in the field of OMBC management. Most studies to date have been retrospective in nature, given the diagnostic challenges of OMBC and studies to date have failed to show conclusive evidence regarding surgery to the primary tumour. Some favourable factors seem to be hormone receptor positivity and bone pre-dominant metastasis, however there is a need for better understanding in the distinct biology of OMBC to characterise and determine the value of surgery to the primary tumour as well as adjuvant oncological treatments.