First-line penpulimab combined with anlotinib achieves complete response in an elderly patient with occult lung squamous cell carcinoma: a case report.

Occult lung cancer is a rare subtype of non-small cell lung cancer (NSCLC), characterized as an aggressive tumor with a poor prognosis. Its diagnosis relies on biopsy and pathological examinations. A durable complete response (CR) in advanced NSCLC achieved with a chemo-free and radiotherapy-free regimen remains exceedingly rare, particularly in elderly patients with a high tumor burden and unknown PD-L1 status. Here, we report an elderly patient who achieved CR of occult lung squamous cell carcinoma (LUSC) after treatment with a combination of penpulimab and anlotinib as first-line therapy. An 83-year-old man with occult LUSC (cTxN3M0, stage IIIB) presented with a mediastinal mass and multiple mediastinal and bilateral supraclavicular lymph node metastases, confirmed by supraclavicular lymph node examination biopsy. The patient was treated with a combination of penpulimab and anlotinib under close safety monitoring, resulting in a rapid tumor response and complete remission after ten cycles. This remission lasted over two years with no adverse effects observed during or after treatment. The therapy with penpulimab and anlotinib was continued for 26 months before being stopped at the patient's request. These results suggest that penpulimab plus anlotinib may be a feasible first-line treatment option for elderly patients with advanced LUSC who cannot tolerate or choose to decline standard therapies. Notably, PD-L1 expression was not assessed because the patient refused testing, which prevents definitive conclusions regarding predictive factors associated with the observed response.