利用硼中子捕獲治療方式針對一復發性耳下腺惡性腫瘤所進行之補救性處置-台灣首次新式標靶性粒子放射治療之臨床試驗

Salvage Boron Neutron Capture Therapy (BNCT) for Recurrent Parotid Adenocarcinoma ¾ Taiwan’s First Clinical Trial of Targeted Particle Radiotherapy

背景： 報告一例復發性耳下腺癌接受台灣首次硼中子捕獲治療臨床試驗的成果。
方法： 在2010 年十月，台灣第一次的硼中子捕獲治療臨床試驗開始並收案了一例51歲復發之左側耳下腺癌的患者。這位患者先前初次診斷治療時曾接受過完全性手術以及術後放射線治療，可是不幸在兩年後疾病復發，疾病透過顱底廣泛地侵犯至左側顳葉腦底部分，導致患者有顱內壓力增加的症狀。患者曾一度接受化學治療以及標靶治療的處置，然均無具體改善的效果，且症狀持續惡化。患者之後先接受部分腦內腫瘤切除且病理證實為復發性耳下腺癌，經評估合適並收案接受臨床硼中子捕獲治療之人體臨床試驗。在間隔30 天的治療療程內, 共接受了兩次計畫性硼中子捕獲治療安排。兩次治療前腫瘤與正常組織含硼藥物（BPA）的濃度比例（Tumor/Normal tissue ratio）分別為4.56以及3.73。患者於整個治療流程中共接受BPA 藥物460 毫克/ 體重公斤重的連續性藥物滴注處置，兩次治療劑量分別在80% 的腫瘤體積中接受了22.3 以及27.5 的生物等效劑量（Gray-Equivalent; Gy-E）。
結果： 在接受過硼中子捕獲治療的處置後六個月內，腫瘤活性及體積在正子攝影及磁振造影的檢查下呈現明顯腫瘤的縮小及改善，腫瘤縮小比例超過九成，且患者僅有照射區塊局部落髮的可復原反應。
結論： 硼中子捕獲治療對於復發耳下腺癌是一可以考慮的補救性治療方式。

Background: To describe the results of recurrent parotid adenocarcinoma after salvage BNCT .
Method: Taiwan’s first Boron Neutron Capture Therapy (BNCT ) clinical trial has started since October 2010. A 51-year-old patient with recurrent adenocarcinoma arisen from left parotid gland was described in this report. Before recurrence, he underwent standard treatment protocol including radical surgery and adjuvant radiotherapy for the primary tumor. However, tumor relapsed and invaded extensively to the left intracranial regions via skull base. Systemic chemotherapy and target therapy were given but disease still progressed. Tumor enlarged rapidly in brain and intracranial pressure was increased. After craniotomy for partial reduction of tumor volume, two fractions of BNCT were performed as salvage purpose within an interval of 30 days. The T/N ratios of BPA were 4.56 and 3.73, respectively. BPA was dripped continuously during the therapy and a total of 460 mg/Body Weight (kg) was delivered. Two BNCT biological equivalent doses of 22.3 and 27.5 Gy-E were respectively delivered at eighty percent of gross tumor volume.
Result: After BNCT , dramatic tumor regression was monitored by FDG-PET (Positron emission tomography with 2-deoxy-2-[fluorine-18] fluoro-D-glucose) and regular MRI (Magnetic resonance imaging) study within six months. More than ninety percent of tumor volume was reduced thereafter. Only alopecia was observed as the most adverse effect.
Conclusion: BNCT is an effective treatment even for intractable recurrent parotid adenocarcinoma.