口腔癌是台灣常見的頭頸癌之一，大部分在初診斷時為局部性疾病。即使疾病進展到後 期，遠端轉移的比例仍然不多。在過去一旦癌症病人有了遠端轉移，即使轉移的數量少或體積 很小（寡量轉移）仍被認為是無法治癒的疾病。因此這類病人大部分接受緩和治療。然而有許 多的文獻顯示在接受積極的治療情況下，寡量轉移的癌症病人比起瀰漫性轉移，可以有較長的 無疾病存活期，這些證據顯示寡量轉移的癌症是有望治癒，而不是完全無法治癒的疾病。 這些現象在很多不同種類癌症上皆有被觀察到，包含大腸直腸癌、黑色素瘤、子宮內膜癌 等。然而口腔癌被報告的資料很少。因此本文報告一位口腔癌病人，合併無法切除的肺單顆轉 移病灶，接受「立體定位燒灼性」及「同步腫瘤內增量」放射治療。在治療完成的四個月後腫 瘤達到完全緩解。而且在最後一次回診追蹤時（完成放射治療兩年後），病人的頭頸部及肺部 區域皆沒有殘存的腫瘤。

Oral cancer, one common subtype of head and neck cancers in Taiwan, mainly presented as a locoregional disease at diagnosis. Even in its late course, distant metastasis is still rare. Previously, once cancer patients with distant metastasis – even in limited number or small size (i.e., oligometastasis) – were considered as having an “incurable” disease. Thus, palliative treatments were recommended. However, several lines of evidence showed that while applying aggressive managements, most oligometastatic cancer patients demonstrated a durable disease-free survival when compared with those patients with disseminated metastases. This observation implicated that oligometastasis may be a ‘potentially curable,’ rather than “incurable” disease status. This phenomenon has been observed in several types of cancers, such as colorectal cancer, melanoma, and endometrium cancer. But, few data were reported in oral cancer. Herein, we presented an oral cancer patient with an un-resectable pulmonary oligometastasis. Stereotactic ablative radiotherapy (SABR) was given in conjunction with Simultaneous Integrated Inner-Escalated Boost (SIEB) technique. Four months after SABR/SIEB, complete response was observed. Moreover, no evidence of cancer disease was noted in both lung and head-and-neck region till the last follow-up (two years after RT).