Thoracic SMARCA4-Deficient Undifferentiated Tumor in a 40-Year-Old Male Welder With No Smoking History.

Thoracic SMARCA4-deficient undifferentiated tumor (TSDUT) is a rare and quite new classification of primary pulmonary malignancy. It is classified as a non-small cell lung cancer, typically associated with smoking, and is highly aggressive. Its clinical features, immunohistochemistry, and pathology are quite unique. In this case report, we describe the clinical course of TSDUT pancoast tumor in a 40-year-old male, without a substantial smoking history, but a significant history of occupational welding.