Attempt to define sentinel node micrometastasis in oral squamous cell carcinoma

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K09620
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 56050:Otorhinolaryngology-related
• Research Institution: Asahi University
• Principal Investigator: MATSUZUKA Takashi 朝日大学, 保健医療学部, 教授 (80336461)
• Co-Investigator(Kenkyū-buntansha): 長谷川 泰久 朝日大学, 歯学部, 教授 (10261207)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: Sentinel lymph node / Lymphatic metastasis / Neck dissection / Micrometastases / Oral carcinoma

Outline of Final Research Achievements

This sentinel node (SN) biopsy trial,included 55 patients from three previous trials, aimed to assess its effectiveness in identifying predictive factors of micrometastases and to determine whether elective neck dissection (END) is necessary in oral squamous cell carcinoma. The relationship between the sizes of the metastatic focus and metastasis in non-sentinel node (NSN) was investigated.
The difference of prevalence between negative- and positive-NSN was statistically significant with regard to age, long diameter of primary site and number of cases with regional recurrence. In comparing the size of largest metastatic focus dividing the number of positive SN, with metastaic focus range of < 3.0 mm in one-positive SN group, there were 18 (33%) negative-NSN and no positive-NSN. Regarding prognosis,3-year overall survival rate of this group and other were 94 % and 73 % (p=0.04), and 3-year recurrence free survival rate of this group and other were 94 % and 51 % (p=0.03), respectively.

Free Research Field

頭頸部腫瘍

Academic Significance and Societal Importance of the Research Achievements

潜在転移リスクのない微小転移の定義についての提案は①SN転移が単発であり②SN内の病巣が3.0 mmかそれより小さいときである。これからもSNの情報を収集し頭頸部癌の微小転移を定義したい。本研究結果からSNの転移が微小であるとき、SNより下流の郭清を省略できる可能性がある。この結果を基にSNが微小転移であった際に、頸部郭清を省略するか、画一的な頸部郭清術を行うかとの治療法の比較・検証を行う前向き比較試験をデザインし次の研究に継承する。