Pathologic complete response to pralsetinib in stage IV RET-positive non-small cell lung cancer: A case report

Neoadjuvant therapy with tyrosine kinase inhibitors has been proposed as a feasible approach for downstaging potential resectable non-small cell lung cancer (NSCLC). Pralsetinib is a paradigm of precision medicine for cancers driven by mutant RET (rearranged during transfection). In this case, we reported dramatic response to Pralsetinib in a stage IV NSCLC patient with RET rearrangement. Strikingly, treatment with 10 months of Pralsetinib impended downstaging of the N2 lymph node and metastatic pleural disease. Histological examination of the surgically resected specimen indicated a pathologic complete response (pCR). The patient was recommended to continue Pralsetinib as an adjuvant therapy. This case highlighted potential application of Pralsetinib in locally advanced RET-positive NSCLC to prime surgical resection. Postoperative Pralsetinib adjuvant therapy should also be considered.