Incidental Oral Artifact Detected by PET/CT Scans Mimicking Local Recurrence in Patients Treated with Chemotherapy for DLBCL

正子攝影可追蹤淋巴癌化療效果並宜分辨口腔假影或局部復發

杜東峻(Dom-Gene Tu) ； 盧彥哲(Yin-Che Lu) ； 董俊良(Chun-Liang Tung) ； 許友齡(Yu-Ling Hsu) ； 涂啟文(Chi-Wen Tu)

《核子醫學暨分子影像雜誌》 28卷1期 (2015/03) Pp. 38-44

https://doi.org/10.6332/ANMMI.2801.006

摘要

評估瀰漫性大B細胞淋巴瘤的臨床治療反應，對於長遠的治療效果評估是有高度預測性的，但是對於該種臨床治療反應的判別仍存在不同的解釋標準。使用正子斷層造影以進行評估藥物治療反應，已被證實可以有效降低未確認的完全反應率，並可以藉由正子造影的高度敏感性與高度特異性而有效評估癌症治療反應。我們報告一個利用氟－18氟化去氧葡萄糖正子斷層造影評估瀰漫性大B 細胞淋巴瘤臨床治療反應的病例。在早期的正子造影結果，仍可看到少量氟－18氟化去氧葡萄糖的攝取，但是已明確顯示該病患對化學治療有良好的反應。在完成治療後的正子造影結果，雖然無任何顯著地氟－18氟化去氧葡萄糖的攝取；然而，在頭頸部，則發現一個異常的對稱影像。該異常影像原本被懷疑是瀰漫性大B細胞淋巴瘤復發或是遠端轉移病灶，但是依據其人工的對稱趨勢以及該病患的既往病史判斷，這是一個使用人工假牙所造成的發炎進而導致異常的氟－18氟化去氧葡萄糖的攝取所產生的假影。因此，使用正子斷層造影確實有助於評估瀰漫性大B細胞淋巴瘤的臨床治療反應。此外，在判讀正子造影結果時，應要特別注意異常的氟－18氟化去氧葡萄糖的攝取所產生的影像；該假影很容易被診斷為腫瘤的轉移或復發。

關鍵字

抗腫瘤聯合化學治療 ； 假影 ； 瀰漫性大B細胞淋巴瘤 ； 正子斷層造影 ； 評估臨床治療反應

並列摘要

Response to primarily clinical therapy in DLBCL is highly predictive of long-term outcome, but the diverse interpretations of response criteria exist. The application of PET/CT with its functional imaging ability has been indicated to cause the eradication of the Unconfirmed Complete Response category and advance the accuracy and specificity of response monitoring after primary therapy. Here, we present a case of DLBCL with monitoring response to primary therapy using F-18 FDG PET/CT. Minimal residual FDG uptake from an interim PET/CT result suggested good response to the clinical chemotherapy. No significant evidence of hypermetabolic lesions were detected in PET/CT scan after finishing the treatment. However, a symmetric pattern of FDG uptake was incidentally noticed in the oral region. This irregular hypermetabolic lesion raised questions about whether it represented recurrences of DLBCL specifically in the head and neck regions. Judged from this artificially symmetric pattern and the past medical history, this abnormal lesion was defined as a dental artifact caused by the usage of removable dental objects. Conclusively, the application of PET/CT for early assessment of therapeutic response critically facilitates the managing for DLBCL patients. Furthermore, carefulness should be taken to be aware of abnormal patterns of FDG uptake which could easily be diagnosed as tumor metastasis or recurrence.

並列關鍵字

antineoplastic combined chemotherapy ； artifacts ； DLBCL ； PET/CT ； treatment outcome