Anaplastic lymphoma kinase-negative pulmonary inflammatory myofibroblastic tumor with multiple metastases and its treatment by Apatinib: A case report

RATIONALE: Primary pulmonary inflammatory myofibroblastic tumor (IMT) with distant metastasis is extremely rare. Moreover, metastasis of pulmonary IMT to bone marrow has never been reported in previous studies. Therapeutic approaches for anaplastic lymphoma kinase (ALK)-negative pulmonary IMT with metastasis are limited. Yet there is no report on the treatment of advanced IMT cases with anti-angiogenesis drugs. PATIENT CONCERNS: We described a patient with a complaint of fatigue, with the chest computed tomography (CT) scan revealing 2 masses in bilateral lung. DIAGNOSES: The CT-guided lung biopsy examined 1 lesion in the right lung, and the post-operative pathological diagnosis of ALK-negative pulmonary IMT was recommended. However, the lung lesions were found significantly enlarged during the subsequent visit 8 months later, along with multiple metastases to the bone and abdominal cavity. A bone marrow biopsy revealed bone marrow infiltration by spindle cells. INTERVENTIONS: The patient began to take Celecoxib due to the rapid progression of IMT, however, resulting in the aggravated gastric ulcer. He stopped taking the medicine 1 month later, with no remarkable change in the lesions by CT. Apatinib was administrated instead of Celecoxib. OUTCOMES: After the 5-month treatment of Apatinib, the mass in the abdominal cavity significantly shrank and the lung lesions slightly decreased in size. With the 9-month administration of Apatinib, the lung lesions and the abdominal mass kept stable, compared with the situation in the 5-month follow-up. LESSONS: Although pulmonary IMT shows the potential of metastasis, its metastasizing to bone marrow is a highly unusual event. Apatinib is effective for pulmonary IMT, and should be taken into consideration for the treatment of inoperable pulmonary IMT patients who lack ALK rearrangement.