Breast metastases from primary lung cancer: a retrospective case series on clinical, ultrasonographic, and immunohistochemical features

Primary lung adenocarcinoma with breast metastasis harboring the EML4‑ALK fusion: A case report

Pulmonary adenocarcinoma with breast metastasis is rarely encountered in clinical practice. Therefore, precise clinical diagnosis of patients with this disease is crucial when selecting subsequent treatment modalities and for overall prognosis assessment. The present study reported on a case of lung cancer with breast metastasis harboring the EML4-ALK fusion. The patient was initially diagnosed with triple-negative breast cancer with lung metastasis, but comprehensive breast cancer treatment was ineffective. Reevaluation of the patient's condition via lung biopsy revealed primary lung adenocarcinoma. In addition, the results of genetic testing revealed the EML4-ALK fusion protein in both lung and breast tissues. After treatment with ALK inhibitors, the patient's symptoms improved rapidly. This case highlights the prolonged diagnostic journey from presentation with a breast mass to ultimately being diagnosed with lung cancer with breast metastasis, underscoring the critical need for heightened awareness among clinicians regarding the possibility of rare metastatic patterns. Timely identification of lung cancer with breast metastasis, facilitated by comprehensive genetic testing, not only refines treatment decisions but also emphasizes the importance of interdisciplinary collaboration in navigating complex clinical scenarios. Such insight contributes to the ongoing development of personalized cancer care that guides clinicians toward more effective and tailored therapeutic strategies for patients with similar diagnostic challenges.

Lung cancer with breast metastasis: a case report and review of the literature

In this article, we present a rare case of breast metastasis of lung cancer. Chest computed tomography (CT) for a woman in her early 50s indicated right lung malignancy, multiple bone metastases, and an irregular mass in her right breast. Further inquiry into the case history revealed that the patient had been aware of the breast mass for 3 years, without respiratory symptoms. Biopsy of the breast mass suggested estrogen receptor (ER) (+), progesterone receptor (PR) (-), and human epidermal growth factor receptor 2 (HER2) (+ +) breast cancer. The patient was initially diagnosed with breast cancer with lung and bone metastasis. However, comprehensive breast cancer treatment was ineffective, and thyroid transcription factor-1 (TTF-1), napsin A, and cytokeratin 7 (CK7) were evaluated to better understand the origin of the cancer. To the best of our knowledge, this patient had the longest reported disease course from presentation with a breast lump as the first symptom to the final diagnosis of breast metastasis of lung cancer. To provide a better reference for differential diagnosis of ambiguous tumors, we also performed a systematic literature review.

Breast metastasis of a lung carcinoma

Breast metastasis is a rare phenomenon (0.2–1.3%)¹ compared to primary breast lesions. Several neoplasms have been reported to metastasize to the breast such as melanoma, lymphoma and lung cancer. In this article, we report a case of breast metastasis of lung cancer confirmed by biopsy and immunohistochemistry with CT and ultrasound imaging.