Extranodal extension in oral squamous cell carcinoma: Clinical and histopathological analysis

Mirai Higaki; Koichi Koizumi; Toshinori Ando; Nanako Ito; Fumitaka Obayashi; Atsuko Hamada; Souichi Yanamoto

doi:10.1016/j.oooo.2024.03.008

Extranodal extension in oral squamous cell carcinoma: Clinical and histopathological analysis

Oral Surg Oral Med Oral Pathol Oral Radiol. 2024 Mar 22:S2212-4403(24)00126-3. doi: 10.1016/j.oooo.2024.03.008. Online ahead of print.

Authors

Mirai Higaki¹, Koichi Koizumi², Toshinori Ando³, Nanako Ito², Fumitaka Obayashi², Atsuko Hamada², Souichi Yanamoto²

Affiliations

¹ Department of Oral Oncology, Division of Dentistry, Graduate School of Biomedical and Health Sciences, Hiroshima University, Minami-ku, Hiroshima Japan. Electronic address: mirai-higaki@hiroshima-u.ac.jp.
² Department of Oral Oncology, Division of Dentistry, Graduate School of Biomedical and Health Sciences, Hiroshima University, Minami-ku, Hiroshima Japan.
³ Center for Oral Clinical Examination, Hiroshima University Hospital, Minami-ku, Hiroshima, Japan.

PMID: 38679502
DOI: 10.1016/j.oooo.2024.03.008

Abstract

Objective: Extranodal extension (ENE) is an important prognostic factor in oral squamous cell carcinoma (OSCC). This study aimed to evaluate the clinical significance of stratifying minor or major ENE in OSCC.

Study design: This retrospective cohort study included 75 patients who had undergone neck dissection for OSCC and were classified as pN+. ENE was measured using hematoxylin-eosin-stained specimens and stratified into major (ENEma, >2 mm) and minor (ENEmi, ≤2 mm) by distance. Their association with survival, locoregional relapse, and distant metastases were assessed.

Results: Of 49 patients with pathological ENE, 23 had ENEmi, and 26 had ENEma. The 5-year overall survival (OS) was 38%, 66%, and 76% in the ENEma, ENEmi, and no ENE groups, respectively. Compared with no ENE, ENEma was associated with significantly decreased 5-year cumulative OS and disease-specific survival. ENEma was a risk factor for decreased OS (HR: 2.54, 95% CI: 1.04-6.18, P = .040) in the multivariable Cox regression analysis, and was associated with distant metastasis.

Conclusion: In patients with OSCC, ENEma is associated with a significantly poorer prognosis; therefore stratifying ENE is clinically relevant. ENEma may increase the risk of distant metastasis; therefore, new treatment modalities that contribute to distant metastasis control are required.