The Art of Diagnosis: Cyto-Histopathological Correlation in Metastatic Lung Cancers - A Rare Case Report

Background

Metaplastic breast carcinoma (MBC), an exceptionally rare and heterogeneous triple-negative subtype of breast cancer, accounts for less than 1% of all breast carcinomas. This case report exemplifies the pivotal role of cytohistological correlation in diagnosing lung metastasis through fine needle aspiration biopsy. The case of a 90-year-old female with a complex medical history is presented, highlighting the importance of careful clinical assessment in metastatic lung cancers.

Case Information

A 90-year-old female, with a history of metaplastic breast carcinoma following a left mastectomy 20 months ago, was admitted due to a four-week history of progressive dyspnea and fatigue. Despite being a non-smoker, she had a history of essential tremor, dementia, and chronic obstructive pulmonary disease. Extensive diagnostic evaluations, including laboratory results and imaging, revealed pulmonary nodules and partially calcified pleural masses bilaterally along with pleural effusions, raising concerns of metastasis. Thoracentesis initially showed negative pathology findings, along with subsequent CT-guided lung biopsies, prompting an investigation into the patient’s prior oncology history.

The patient's past oncology reports were revisited, uncovering a diagnosis of metaplastic carcinoma with mesenchymal differentiation in the breast. Cytohistological correlation was performed, ultimately confirming the presence of malignant cells in the lung biopsy, leading to the diagnosis of stage IV triple-negative metaplastic breast carcinoma with malignant pleural effusion.

Conclusions

Metaplastic breast carcinoma is characterized by the differentiation of malignant cells toward mesenchymal and squamous elements, making it a rare and heterogeneous cancer. The patient's case, with lung metastasis originating from a metaplastic breast carcinoma, is a rare occurrence, further emphasizing the importance of accurate diagnosis in such unique situations. The report underscores the significance of meticulous medical history collection, interdisciplinary communication, expert consultation, and cyto-histopathological correlation in achieving accurate pathological and clinical diagnoses in metastatic lung cancers.

Metaplastic breast carcinoma's rarity and heterogeneity contribute to its generally poor prognosis, with factors like advanced age, high-grade tumors, and distant metastasis reducing survival rates. In most cases, surgical resection remains the primary treatment approach, followed by platinum-based chemotherapy. Promising treatment avenues, including immunotherapy and molecular targeted therapies, may improve patient outcomes, but these options depend on individual circumstances.

In the case presented here, the patient's age and comorbidities influenced the decision to opt for hospice care, highlighting the importance of tailoring treatment strategies to a patient's unique situation. This case report not only sheds light on a rare occurrence but also serves as a reminder of the importance of comprehensive medical assessments in managing complex clinical scenarios.