The types of investigation undertaken by a general practitioner depend on many factors including access to diagnostic tests and medical specialists and the patient’s preferences. General practitioners should refer all patients with a suspicious sign or symptom to a breast assessment clinic.

General practitioner examinations and investigations should include a triple test of three diagnostic components:

• medical history and clinical breast examination
• imaging – mammography and/or ultrasound
• non-excision biopsy – preferably core biopsy (Cancer Australia 2017a; Farshid et al. 2019). Pathologists should expedite such testing as part of routine clinical care. Funding through the Medicare Benefits Schedule is accessible for receptor profile evaluation of screen-detected cancers, including immunohistochemistry for ER, PR and HER2 and, when necessary, in situ hybridisation to assess HER2 gene amplification.

Fine-needle aspiration biopsy does not permit distinction between invasive cancer and in situ malignancy. Evaluation of grade and subtype are not reliable, and cytology is inappropriate for assessing a cancer’s receptor profile (ER, PR, HER2), critical for optimal treatment planning, including suitability of neoadjuvant therapy. Fine-needle aspiration cytology may be considered if the clinical and imaging features suggest a benign process, particularly a cystic lesion. If cytology results are non-diagnostic, atypical, suspicious or malignant, core biopsy is needed.

Based on the best available evidence, the triple test provides the most effective means of excluding breast cancer in patients with breast symptoms. A positive result on any component of the triple test warrants referral for specialist surgical assessment and/or further investigation, irrespective of any other normal test results. This implies that not all three components of the triple test need to be performed to reach the conclusion that appropriate referral is needed. The triple test is positive if any component is indeterminate, suspicious or malignant (Cancer Australia 2017a).

For screen-detected lesions, a 2020 review by Cancer Australia established that core biopsy (including vacuum-assisted core biopsy) is the procedure of choice for assessing most screen-detected breast abnormalities (Cancer Australia 2020c). Fine-needle aspiration in the screening setting is appropriate for simple cysts, some complex cystic lesions, axillary lymph nodes and rare situations where a core biopsy is hazardous or technically difficult.

BreastScreen Australia services take responsibility for screening and investigation of screen-detected lesions, including needle biopsies. After multidisciplinary assessment and review of results, recommendations are made for the next steps in management. The woman and her general practitioner are advised of these recommendations in writing. Surgery and ongoing care are typically not part of the BreastScreen program and must be coordinated by the general practitioner through appropriate surgical referral.

To enable timely treatment planning, including consideration of neoadjuvant therapies, it is preferable that the histologic findings, including the receptor profile results, be available in time for the patient’s first consultation with the treating surgeon. Information could be provided to patients to enable them to make an informed decision on neoadjuvant therapy. See Breast Cancer Trials ‘Neoadjuvant patient decision aid’ brochure.