Takuma Sho, Karayama Masato, Suzuki Risa, Miyashita Koichi, Inoue Yusuke, Yasui Hideki, Hozumi Hironao, Suzuki Yuzo, Furuhashi Kazuki, Enomoto Noriyuki, Fujisawa Tomoyuki, Inui Naoki, Suda Takafumi
Second Division, Department of Internal Medicine, School of Medicine, Hamamatsu University, 1-20-1 Handayama Chuoku, Hamamatsu, 431-3192, Japan.
Department of Clinical Pharmacology and Therapeutics, School of Medicine, Hamamatsu University, 1-20-1 Handayama Chuo-ku, Hamamatsu, 431-3192, Japan.
Respir Med Case Rep. 2025 Jul 5;57:102260. doi: 10.1016/j.rmcr.2025.102260. eCollection 2025.
Photoimmunotherapy (PIT) using cetuximab-sarotalocan sodium (CS) is a novel therapy for unresectable or locally recurrent head and neck squamous cell carcinoma (HNSCC). CS is a conjugate of cetuximab (monoclonal antibody targeting epidermal growth factor receptor [EGFR]) and IR700 (light-activatable dye). Intravenously administered CS binds to cancer cells expressing EGFR. Upon exposure to a 690 nm wavelength laser, the conjugated IR700 is photoactivated and induces a photochemical reaction that damages the tumor cells. While CS-PIT showed a favorable safety profile in an HNSCC clinical trial with no cases of drug-induced interstitial lung disease (DIILD), cetuximab is known to cause DIILD, especially in patients with pre-existing interstitial lung disease (ILD).
A 79-year-old man with recurrent HNSCC after surgery and adjuvant chemoradiotherapy received CS-PIT. Pre-treatment high-resolution chest computed tomography (HRCT) revealed mild ILD in the lower lobes of both lungs. Two months after CS-PIT, he developed severe DIILD with hypoxia. He received two cycles of intravenous methylprednisolone (1 g/day, 3 days/cycle) followed by oral prednisolone at 1 mg/kg/day, which was gradually tapered. After the high-dose corticosteroid therapy, the DIILD improved.
We report the first case of DIILD caused by CS-PIT. Because cetuximab is a component of CS, CS-PIT has the potential to induce DIILD. Risk assessments and monitoring for DIILD are recommended for patients receiving CS-PIT.
使用西妥昔单抗-沙罗他洛钠（CS）的光免疫疗法（PIT）是一种针对不可切除或局部复发头颈部鳞状细胞癌（HNSCC）的新型疗法。CS是西妥昔单抗（靶向表皮生长因子受体[EGFR]的单克隆抗体）与IR700（光可激活染料）的偶联物。静脉注射的CS与表达EGFR的癌细胞结合。在暴露于690nm波长的激光后，偶联的IR700被光激活并引发光化学反应，从而损伤肿瘤细胞。虽然在一项HNSCC临床试验中CS-PIT显示出良好的安全性，未出现药物性间质性肺病（DIILD）病例，但已知西妥昔单抗会导致DIILD，尤其是在已有间质性肺病（ILD）的患者中。
一名79岁男性，在接受手术及辅助放化疗后出现复发性HNSCC，接受了CS-PIT治疗。治疗前的高分辨率胸部计算机断层扫描（HRCT）显示双肺下叶有轻度ILD。CS-PIT治疗两个月后，他出现了伴有低氧血症的严重DIILD。他接受了两个周期的静脉注射甲泼尼龙（1g/天，3天/周期），随后口服泼尼松龙，剂量为1mg/kg/天，并逐渐减量。经过高剂量糖皮质激素治疗后，DIILD有所改善。
我们报告了首例由CS-PIT引起的DIILD病例。由于西妥昔单抗是CS的组成部分，CS-PIT有诱发DIILD的可能性。建议对接受CS-PIT治疗的患者进行DIILD的风险评估和监测。
