Metastatic Breast Cancer in a Patient with Neurofibromatosis Type I: A Rare Case Report Highlighting Aggressive Disease and Management Challenges

Neurofibromatosis Type 1 (NF1) is a genetic condition caused by a mutation in the NF1 tumour suppressor gene and is associated with a high risk of malignancies, especially breast cancer. Individuals with NF1 face an exceptionally high burden of cancer. Breast cancer is of special concern in NF1, with the risk being increased in women younger than 50 years. NF1-associated breast cancer appears to be more aggressive, often presenting as the basal subtype, and has been noted to occur at an earlier age. This case report describes a 45-year-old female with NF1 who was diagnosed with right-sided triple-negative breast cancer. She received adjuvant chemotherapy and radiotherapy but did not follow up regularly. Two years later, she developed widespread metastatic disease in her liver, bones, lungs, and pleura, with imaging revealing extensive metastases and lymphangitic carcinomatosis. Breast cancer in NF1 patients usually develops at a younger age and is more aggressive, as illustrated in this case. Patients with confirmed NF1 should undergo regular screening starting at the age of 30 years, and any suspicious mass should be biopsied. Most cases are basal; hence, discussions in a multidisciplinary tumour board are essential. Neoadjuvant chemotherapy can provide a survival advantage. Given that radiation therapy in NF1 can cause fibrosis and lead to secondary malignancies, its use should be limited wherever possible. This report emphasises the high risk of breast cancer in NF1, the management of the disease, and the necessity of early detection to improve patient outcomes.