Primary Pulmonary Leiomyosarcoma Managed With Pazopanib: A Case Report and Literature Review.

Primary pulmonary leiomyosarcoma (PPL) arises from pulmonary smooth muscle tissue, with less than 0.5% incidence among pulmonary malignancies and 30% among primary pulmonary sarcomas. Here, we present a case of PPL managed with pazopanib. Moreover, a brief review of relevant literature was conducted. A 65-year-old female presented with chronic cough, weight loss, and recurrent pneumonia, with a medical history including diabetes mellitus, hypertension, and hyperlipidemia, as well as past surgical colectomy and hysterectomy (due to abnormal uterine bleeding with normal pathology and no evidence of uterine leiomyosarcoma). Upon admission, she exhibited fever, cough, dyspnea, and decreased breath sounds over the upper lung lobe. Diagnostic workups revealed a large pulmonary mass, diagnosed as leiomyosarcoma via core needle biopsy and subsequent immunohistochemical staining. Neoadjuvant treatment with ifosfamide and adriamycin followed by chemoradiotherapy was attempted, but surgery for tumor resection was not feasible. Then, gemcitabine and docetaxel were chosen as the new treatment after ifosfamide and adriamycin were not effective. Imaging revealed tumor not reacting to latest treatment, either. Given the disease's persistence and the patient's diminished capacity for chemotherapy, the patient is presently undergoing pazopanib treatment, with ongoing monitoring of its effects. After 3 months of treatment with pazopanib (administered orally at 200 mg twice daily), the patient experienced a significant reduction in tumor size, with a notable decrease from 135 mm to 80 mm, approximating one-third of the initial size, indicating a positive therapeutic effect. This case report provides preliminary evidence suggesting that pazopanib, an oral multi-tyrosine kinase inhibitor, may be a promising therapeutic option for the management of PPL. However, further in-depth and long-term studies are warranted to evaluate the clinical efficacy and superiority of this treatment.