Metastatic screening for patients with newly diagnosed breast cancer: Who and how?

Abstract

Globally, breast cancer is the most prevalent cancer affecting women and the incidence in low-middle income countries (LMICs) is predicted to rise as life expectancy increases. 1 The stage at the time of presentation differs between high-income countries (HICs) and LMICs. In the United States, between 35% (uninsured population) and 76% (insured population) of women, aged between 50 and 74 years, had a mammogram in the preceding 2 years. This contrasts with figures from a 2003 World Health survey where only 2.2% women in LMICs aged 40-69 received any breast screening. 2,3 While accurate statistics are not available for SA, it is estimated that between 50% and 60% of women present with locally advanced or metastatic breast cancer. 4,5 This figure compares unfavourably to those from HICs (many of whom have population-based screening programmes) where approximately 5% of women present with the metastatic disease. 6 Staging, as defined by the American Joint Committee on Cancer (AJCC), has historically been limited to anatomical staging. While the eighth version of the AJCC guidelines 7 has been altered to include tumour biology, anatomical staging still holds a place, as it allows for population studies, provides a concise summary of the patient, gives an indication of tumour biology, permits comparative population-based studies and guides treatment. However, some controversy exists Background: Staging for breast cancer patients, as defined by the American Joint Committee on Cancer (AJCC), has historically been limited to anatomical staging. However, the eighth version of the AJCC guidelines has been altered to include tumour biology. Anatomical staging still has a place especially in low-middle income countries where the majority of patients present with locally advanced or metastatic disease.Aim: This review article considers which newly diagnosed breast cancer patients should be referred for anatomical staging and the pros and cons of the different modalities available in South Africa. Method:The different modalities available were reviewed with respect to metastatic screening for asymptomatic women. The usefulness of the modalities were considered with reference to organ-specific disease rather than the stage of the patient.Results: Any person with newly diagnosed breast cancer and symptoms suggestive of systemic involvement should be investigated. All symptomatic women who present with a tumour larger than 5 cm, radiological or clinical evidence of nodal disease, triple negative or HER2+ve tumours should have metastatic screening. This gives information about the primary as well as the metastatic status. Conclusion:However, increasingly, the major determinant of treatment is the biology of the cancer and not the anatomical stage. In future, this trend is likely to increase with anatomical staging becoming less important.