Ohta Ryuichi, Tanaka Kaoru, Miyata Masayuki, Tanizaki Junko, Hayashi Hidetoshi
Community Care, Unnan City Hospital, Unnan, JPN.
Medical Oncology, Kindai University Faculty of Medicine, Sayama, JPN.
Cureus. 2025 Apr 18;17(4):e82530. doi: 10.7759/cureus.82530. eCollection 2025 Apr.
We report a case of a 64-year-old man with advanced non-small cell lung cancer (NSCLC) who developed peritoneal metastasis during systemic treatment. Initially diagnosed with lung adenocarcinoma with pleural dissemination and bone metastases, he received carboplatin, pemetrexed, and pembrolizumab, followed by docetaxel due to clinical progression. While primary lung lesions responded to docetaxel, the patient developed new-onset abdominal pain and ascites. Radiologic findings suggested peritoneal thickening, raising suspicion for either docetaxel-induced toxicity or disease progression. Given the rarity of peritoneal metastasis in NSCLC and concurrent treatment response elsewhere, drug-induced complications were initially considered. However, worsening symptoms and further imaging prompted cytological evaluation of ascitic fluid, which confirmed metastatic adenocarcinoma consistent with lung origin. This case highlights the diagnostic challenge of distinguishing treatment-related adverse events from disease progression, especially in patients presenting with nonspecific abdominal symptoms during therapy. Clinicians should maintain a high index of suspicion for uncommon metastatic sites when new symptoms arise, even in the setting of apparent response at the primary site.
我们报告一例64岁晚期非小细胞肺癌（NSCLC）男性患者，其在全身治疗期间发生了腹膜转移。该患者最初诊断为伴有胸膜播散和骨转移的肺腺癌，接受了卡铂、培美曲塞和帕博利珠单抗治疗，后因临床进展接受多西他赛治疗。虽然原发性肺部病变对多西他赛有反应，但患者出现了新发腹痛和腹水。影像学检查结果提示腹膜增厚，怀疑是多西他赛引起的毒性反应或疾病进展。鉴于NSCLC中腹膜转移罕见且其他部位有治疗反应，最初考虑为药物引起的并发症。然而，症状恶化及进一步影像学检查促使对腹水进行细胞学评估，结果证实为与肺原发灶一致的转移性腺癌。该病例凸显了区分治疗相关不良事件与疾病进展的诊断挑战，尤其是在治疗期间出现非特异性腹部症状的患者中。即使在原发部位有明显反应的情况下，当出现新症状时，临床医生对不常见转移部位也应保持高度怀疑。
