A Rare Case of Pleomorphic Carcinoma of the Lung Harboring an Anaplastic Lymphoma Kinase (ALK) Rearrangement

Anaplastic lymphoma kinase (ALK)-rearranged pulmonary pleomorphic carcinoma successfully treated with crizotinib

Pulmonary pleomorphic carcinoma (PPC) is rare, and the response of patients to conventional chemotherapy is very poor. Here we present a patient with anaplastic lymphoma kinase (ALK)-rearranged advanced PPC treated with crizotinib. Computed tomography revealed a mass in the left upper lung of a nonsmoking 60-year-old woman. Pathological findings using resected tissue were consistent with PPC stage 1A, T1bN0M0. Although the patient received adjuvant radiotherapy, the disease relapsed, quickly progressed, and remained PPC according to analysis of biopsied tissue. Although negative for epidermal growth factor receptor mutations, ALK rearrangements were detected in adenocarcinoma and spindle-cell components. The patient received crizotinib therapy and achieved a partial response for 7 months. This case indicates that patients with PPC, particularly those with adenocarcinoma, may harbor an epithelial component with the ALK rearrangement. Although the progression-free survival of patients treated with crizotinib is limited, they may obtain more benefit compared with conventional chemotherapy.

Pulmonary Sarcomatoid Carcinoma with ALK Rearrangement: Frequency, Clinical-Pathologic Characteristics, and Response to ALK Inhibitor

PURPOSE: The incidence of anaplastic lymphoma kinase (ALK) rearrangement in pulmonary sarcomatoid carcinoma (PSC) is controversial. In this study, we aimed to reveal the reliable frequency and the clinical-pathologic characteristics of pulmonary sarcomatoid carcinoma (PSC) with ALK rearrangement in Chinese population, and to provide insight into the translatability of anti-ALK treatment in this treatment-refractory disease. METHODS: Immunohistochemistry (IHC) using a Ventana anti-ALK (D5F3) rabbit monoclonal antibody was performed in 141 PSC specimens collected from multiple medical centers. IHC-positive cases were then confirmed using ALK fluorescent in situ hybridization (FISH). The incidence rates and clinical-pathologic characteristics of ALK-rearranged PSC were then analyzed. Response to ALK inhibitor crizotinib in a patient with ALK-rearranged PSC was evaluated according to the response evaluation criteria for solid tumors (RECIST) version 1.1. RESULTS: Five of 141 (3.5%) of PSCs showed ALK rearrangement-positive by IHC and then were confirmed by FISH. Two were carcinosarcomas and the other three were pulmonary pleomorphic carcinoma (PPC). Strong positive ALK rearrangement was observed in both the epithelioid and sarcomatoid components. The median age of ALK-positive patients was younger than that of ALK-negative patients. PSCs in never-smokers were more likely to harbor ALK rearrangement than those in former or current smokers (P < .05). A 40-year-old woman diagnosed with ALK-rearranged PPC experienced a partial response (−32%) to the ALK inhibitor crizotinib. CONCLUSIONS: The incidence rates of ALK rearrangement in PSC in the Chinese population are similar to those of other subtypes of NSCLC. PSCs in younger never-smokers are more often to harbor ALK rearrangement. ALK inhibitors may serve as an effective treatment for ALK-rearranged PSC.