[SWI/SNF chromatin remodeling complex BAF subunit-deficient lung carcinoma: a case report].

Area of Science:

• Oncology
• Genetics
• Immunotherapy

Background:

• SMARCB1-deficient lung carcinoma is a rare subtype of non-small cell lung cancer.
• This deficiency may influence tumor behavior and response to treatment.
• Immunotherapy has shown potential in various advanced lung cancers.

Purpose of the Study:

• To report a case of SMARCB1-deficient lung carcinoma.
• To evaluate the treatment response and survival in a patient with this rare condition.
• To highlight the potential role of immunotherapy in managing SMARCB1-deficient lung carcinoma.

Main Methods:

• Case presentation of an elderly male with persistent cough.
• Diagnosis confirmed by bronchoscopic biopsy and immunohistochemical staining (SMARCB1, SMARCA4, PD-L1, Ki-67).
• Treatment with a combination of chemotherapy and immunotherapy.

Main Results:

• Immunohistochemistry revealed SMARCB1 deficiency, SMARCA4 positivity, high PD-L1 expression (60%), and high Ki-67 proliferation index (60%).
• The patient received one cycle of combined chemotherapy and immunotherapy.
• The patient has survived for 34 months with ongoing tumor presence, indicating a positive response to treatment.

Conclusions:

• SMARCB1-deficient lung carcinoma, though rare, can be managed with chemotherapy and immunotherapy.
• High PD-L1 expression in this subtype may predict response to immunotherapy.
• This case suggests that immunotherapy could be a viable treatment option for SMARCB1-deficient lung carcinoma, warranting further investigation.