The objective of this report is to present the use and efficacy of ado-trastuzumab as an advanced line of therapy in salivary duct carcinoma (SDC) patient. An 84-year-old gentleman diagnosed with metastatic salivary duct tumor harboring overexpressed human epidermal growth factor receptor-2 has gone through resection surgery. The first line of treatment included initial doublet chemotherapy combined with trastuzumab, which was continued later as maintenance. PET-CT follow-up for 4 years has demonstrated no evidence of disease. However, upon recurrence, use of Ado-trastuzumab emtansine was prompted as second-line of treatment. This targeted patient-tailored therapy has accomplished a complete response. The effectiveness of ado-trastuzumab emtansine was notable within a short time period of two treatment cycles leading to full recovery. Specific agents aimed at altered oncogenes should be considered as a potential drug of choice in neoadjuvant HER2 positive SDC.

中文翻译：

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病例报告：ado-trastuzumab 作为 HER2 阳性唾液管癌的二线治疗。

本报告的目的是介绍 ado-trastuzumab 作为先进疗法在唾液管癌 (SDC) 患者中的用途和疗效。一位 84 岁的先生被诊断患有转移性唾液管肿瘤，该肿瘤含有过度表达的人类表皮生长因子受体 2，已接受切除手术。一线治疗包括初始双重化疗联合曲妥珠单抗，随后继续维持治疗。4 年的 PET-CT 随访未显示任何疾病证据。然而，复发后，建议使用 Ado-trastuzumab emtansine 作为二线治疗。这种针对患者的针对性治疗已取得完全缓解。ado-trastuzumab emtansine 在两个治疗周期的短时间内效果显着，导致完全康复。针对改变癌基因的特定药物应被视为新辅助 HER2 阳性 SDC 的潜在选择药物。