Abstract Background: Breast cancer is the most commonly diagnosed malignancy in women and the second leading cause of cancer death. While bone, lung, liver, and regional lymph nodes are frequent sites of metastasis, laryngeal involvement is exceedingly rare, accounting for 1% of all laryngeal tumors, with breast cancer representing an uncommon primary source. Diagnosis can be challenging when laryngeal lesions present as the sole clinical manifestation of recurrence. Case Presentation: A 79-year-old woman with history of hormone receptor-positive, HER2-negative, high-risk luminal breast cancer (stage IIB) diagnosed in 2015, previously treated with mastectomy, adjuvant chemotherapy (docetaxel/cyclophosphamide), and seven years of endocrine therapy, presented with progressive hoarseness and a 10-pound unintentional weight loss over four months. She denied dysphagia, decreased appetite, recent infections, neck trauma, surgery, or tobacco and alcohol use. On physical examination, the larynx was midline with mild left-sided tenderness, but no palpable cervical or supraclavicular lymphadenopathy. Flexible laryngoscopy revealed left vocal cord swelling, reduced mobility and fullness of the left aryepiglottic fold. Computed tomography (CT) revealed a left laryngeal mass destroying the thyroid cartilage, associated left level II lymphadenopathy, and lytic bone lesions in the right sixth rib and T11 vertebra, concerning for metastatic disease. Biopsy of the laryngeal lesion confirmed poorly differentiated carcinoma, which was strongly estrogen receptor-positive (100%), moderately progesterone receptor-positive (30%), HER2-negative, high Ki-67 (30%). Immunohistochemistry supported metastatic breast carcinoma. Positron emission tomography-CT showed intense FDG uptake in the laryngeal mass (SUVmax 15.1) and multiple skeletal metastases, without visceral involvement. Intensity-modulated radiation therapy was administered to the larynx for local control and symptom palliation. Antiestrogen therapy with letrozole was initiated, with plans to add a CDK 4/6 inhibitor after the completion of radiation. Given her diffuse bony disease, she was started on monthly denosumab, with radiation planned for symptomatic bony lesions. Discussion: Laryngeal metastasis from breast cancer is exceedingly rare and carries a poor prognosis, typically signaling disseminated disease. Laryngeal involvement usually presents with nonspecific symptoms such as dysphonia, chronic cough, dysphagia, or stridor, which are often misattributed to benign conditions or primary laryngeal cancer, leading to diagnostic delays. Hormone receptor status is a key determinant of prognosis and mortality in metastatic breast cancer, including rare sites like the larynx. ER-positive metastatic disease is associated with longer median survival, whereas triple-negative breast cancer has the poorest prognosis and highest mortality. Notably, receptor status can change between the primary tumor and metastatic sites; thus, biopsy and reassessment of receptor status in metastatic lesions is recommended, as it may impact both prognosis and therapeutic options. Management remains multidisciplinary, with systemic endocrine therapy preferred for hormone receptor-positive disease and localized radiotherapy for symptom control. Conclusion: Laryngeal metastasis from breast cancer, though rare, should be considered in patients presenting with persistent hoarseness or other unexplained laryngeal symptoms. Improved survival among breast cancer patients has increased the risk of metastasis to uncommon sites, underscoring the importance of vigilant follow-up and a high index of suspicion for atypical presentations. Timely diagnosis and individualized therapy are essential to optimize outcomes and maintain quality of life. Citation Format: D. Samat, S. Iqbal, M. Haas, N. Leasure, S. Singh. A Rare Case of Breast Cancer Recurrence Presenting as Laryngeal Metastasis abstract. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS5-06-05.
Samat et al. (Tue,) studied this question.