Case Report: Cracking the case: unique presentation of pulmonary sarcomatoid carcinoma with spherical lung metastases.

Background: Pulmonary sarcomatoid carcinoma (PSC) is rare among lung malignancies, but it has a high degree of malignancy, and the average survival time for clinically diagnosed patients with PSC is less than 1 year. There are few reports of multiple solid spherical metastases in the lungs of patients with PSC. Case presentation: This case presents an 80-year-old male with a history of Alzheimer's disease who was hospitalized due to a frequent dry cough. A 16-slice computed tomography examination of the chest revealed multiple solid, egg-sized lesions with smooth borders in both lungs. Because this type of medical imaging data is very rare in clinical practice, the patient's diagnosis was initially confusing. Given that the patient had no history of fever and no special abnormalities in the results of laboratory tests, the multidisciplinary team (MDT) suggested that lung metastases or lung malignancies with intrapulmonary metastasis should be considered. A magnetic resonance imaging (MRI) examination of the head was performed and revealed brain metastatic lesion. Finally, a puncture biopsy of the lung lesion was performed under ultrasound guidance. The case results confirmed PSC. Conclusion: This case presents a very rare medical imaging dataset of solid lesions with multiple egg-sized having smooth borders in both lungs. This special medical imaging data highlights the variability of PSC imaging and the complexity of accurate diagnosis, aiming to improve the understanding of PSC.