The relationship between primary breast and primary lung cancer: A case series

Prior to the initiation of curative treatment, patients with a confirmed breast malignancy undergo staging to assess for the presence of any metastasis. There are instances where instead of metastatic lesions, the patient is diagnosed with a primary lung malignancy. This is identified when the patient is given chemotherapy directed at the breast primary, but the lung lesion does not improve on imaging. Lung biopsy then confirms this diagnosis. Case Series: This case series highlights three such patients who were treated at Mater Dei Hospital, Malta. All three were first diagnosed with the breast malignancy and were later found to have a second primary in the lung. Management of these patients was always through a multidisciplinary team approach, involving the breast surgeons, cardiothoracic surgeons, the oncologist, respiratory physicians, breast and lung specialized radiologists, and the breast care nurses. Relevant literature is also discussed with a focus on synchronous breast and lung malignancies. Conclusion: The main conclusion from this case series is that it would be beneficial if all patients with breast cancer are regularly screened for a lung malignancy/metastasis by at least a chest X-ray. It is important to keep in mind the link between the two organs and the potential presence of a separate lung primary.