A 46-year-old female was admitted with a 20-day history of cough and sputum production, accompanied by chest tightness and dyspnea for over 10 days. Laboratory tests revealed a white blood cell count of 10.55×109/L, elevated neutrophil count (6.59×109/L), and platelet count of 435×109/L. Tumor markers were within normal limits. Chest CT (Fig. 1A, B) demonstrated a linear soft tissue density within the left main bronchus causing obstructive atelectasis, with mild enhancement of the endobronchial lesion post-contrast. Bronchoscopy (Fig. 1C) revealed a bar-shaped neoplasm completely obstructing the left main bronchial orifice, extending cranially to the carina for 3–4cm, and exhibiting respiratory movement. Whitish necrotic material was observed on the tumor surface. Endobronchial tumor resection was performed using an electrosurgical knife via flexible bronchoscopy. A diagnosis of undifferentiated carcinosarcoma was established (Fig. 1D). Pulmonary carcinosarcoma, an exceptionally rare malignancy exhibiting both carcinomatous and sarcomatous histology, accounts for <1% of all lung cancers [1]. It demonstrates a strong male predominance (male-to-female ratio ≈7.25:1) with a median onset age of 65 years. Tobacco smoking is recognized as the primary risk factor. Surgical resection constitutes the mainstay of treatment. Prognosis remains poor, with a 5-year survival rate of approximately 6%. Early diagnosis and multimodal therapy are critical for optimizing outcomes in this highly aggressive tumor.
Chest CT (A, B) demonstrated a linear soft tissue density (arrows) within the left main bronchus causing obstructive atelectasis, with mild enhancement of the endobronchial lesion post-contrast. Bronchoscopy (C) revealed a bar-shaped neoplasm completely obstructing the left main bronchial orifice, extending cranially to the carina for 3–4cm. Under the microscope (D), cells are tightly packed with deeply stained nuclei and lightly stained cytoplasm. Cells are irregular in shape and size, with evident mitotic figures.
Q.L.Z. contributed to the acquisition and analysis of data; B.L.L. contributed to drafting the text and preparing the figures.
DeclarationNever used any artificial intelligence tools or technologies to assist in generating the paper.
FundScience and Technology Program of Jiangxi Provincial Health Commission (No. 202511053).
Conflict of interestThe authors disclose no conflicts.