Low Grade Pulmonary Spindle Cell Neoplasm in a 30-Year-Old Asymptomatic Female: A Diagnostic Dilemma: A Case Report.

Pulmonary spindle cell carcinoma is a highly malignant rare variant of sarcomatoid lung carcinomas. This is a case of an asymptomatic 30-year-old Filipino female with an incidental finding of pulmonary nodules on chest x-ray. Patient was diagnosed with Wilms tumor at the age of 2, S/P nephrectomy with no documented recurrence thereafter. Computed tomography (CT) chest scan showed non-calcified fat density nodules in her right upper, middle and lower lobe. A positron emission tomography (PET) CT scan identified lobulated pulmonary mass with low-grade metabolic activity. Video Assisted Thoracic Surgery with wedge resection of the right lung was done. Final biopsy noted fibroepithelial lesions in the parenchyma which composed of bland spindle cells. ER, SMA, desmin, and caldesmon were diffusely positive consistent with a low-grade spindle cell neoplasm. Genetic testing showed CTNNB1 S45F subclonal mutations. No chemotherapy nor radiotherapy were done. Repeat PET CT of the whole body showed a decrease in size of the mass.