Rethinking Radiation Therapy for Perineural Invasion in Oral Cancer: Does More Coverage Improve Outcomes?
- PMID: 40792421
- PMCID: PMC12340603
- DOI: 10.1002/cam4.71134
Rethinking Radiation Therapy for Perineural Invasion in Oral Cancer: Does More Coverage Improve Outcomes?
Abstract
Introduction: Perineural invasion (PNI) in oral squamous cell carcinoma (OSCC) is linked to aggressive tumour behaviour and poorer survival outcomes. Adjuvant radiotherapy (RT) is recommended for PNI-positive OSCC, but optimal RT target volume remains uncertain.
Methods: This study retrospectively analysed 103 patients with histopathologically confirmed PNI-positive OSCC treated between January 2017 and December 2023. All patients underwent surgery followed by adjuvant RT, with or without concurrent chemotherapy. Recurrence patterns were categorised as in-field, marginal or out-of-field. Survival outcomes, including overall survival (OS) and disease-free survival (DFS), were assessed using the Kaplan-Meier method, and prognostic factors were analysed using univariate and multivariate models.
Results: The median follow-up was 22.2 months. The 2-year OS and DFS were 63% (95% CI: 53%-75%) and 57% (95% CI: 48%-68%), respectively. In-field recurrences constituted 70% of local failures, with no recurrences observed at the skull base despite conservative RT volumes. Extensive PNI, large nerve involvement and extratumoral spread were significantly associated with higher recurrence rates and poorer survival. Multivariate analysis identified advanced tumour stage (T3/T4) and extranodal extension (ENE) as independent predictors of worse OS (HR: 2.67, p = 0.016; HR: 2.08, p = 0.045, respectively), while depth of invasion (DoI) > 10 mm significantly impacted DFS (HR: 0.28, p = 0.04 for DoI ≤ 10 mm).
Conclusion: Our findings suggest that expanding RT volumes to cover entire cranial nerve pathways may not improve outcomes and increase the risk of toxicity. A personalised approach to RT planning, incorporating PNI extent, nerve involvement and other high-risk features, is essential for optimising treatment outcomes in PNI-positive OSCC.
Keywords: oral squamous cell carcinoma; perineural invasion; radiation therapy; recurrence patterns; survival outcomes; target volumes.
© 2025 The Author(s). Cancer Medicine published by John Wiley & Sons Ltd.
Conflict of interest statement
The authors declare no conflicts of interest.
Figures
Similar articles
-
Predictors of recurrence, and the impact of adjuvant radiation therapy on survival in early stage (pT1-2, N0) oral cavity squamous cell carcinoma: A matched pair analysis.Oral Oncol. 2025 Sep;168:107566. doi: 10.1016/j.oraloncology.2025.107566. Epub 2025 Aug 5. Oral Oncol. 2025. PMID: 40753828
-
Tumor Budding as an Independent Prognostic Histopathological Marker in Oral Squamous Cell Carcinoma - An Indian Tertiary Care Center Experience.Turk Patoloji Derg. 2025;41(2):31-41. doi: 10.5146/tjpath.2025.13761. Turk Patoloji Derg. 2025. PMID: 40091314 Free PMC article.
-
Adjuvant Chemoradiotherapy for Oral Cavity SCC With Minor and Major Extranodal Extension.JAMA Otolaryngol Head Neck Surg. 2025 Aug 1;151(8):785-794. doi: 10.1001/jamaoto.2025.1721. JAMA Otolaryngol Head Neck Surg. 2025. PMID: 40531540
-
The role of perineural invasion in treatment decisions for oral cancer patients: A review of the literature.J Craniomaxillofac Surg. 2017 Jun;45(6):821-825. doi: 10.1016/j.jcms.2017.02.022. Epub 2017 Feb 24. J Craniomaxillofac Surg. 2017. PMID: 28359633
-
Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment.Cochrane Database Syst Rev. 2023 Aug 31;8(8):CD006205. doi: 10.1002/14651858.CD006205.pub5. Cochrane Database Syst Rev. 2023. PMID: 37650478 Free PMC article.
References
-
- Chaturvedi P., Byakodi S., Hiremath S., et al., “Oral Cancer in India: Epidemiological and Clinical Aspects,” Journal of the Indian Medical Association 113, no. 7 (2015): 37–42.
-
- Ministry of Health and Family Welfare , “Global Adult Tobacco Survey, India, 2017,” 2017.
-
- GLOBOCAN , “GLOBOCAN 2022: Global Cancer Statistics,” 2022, https://gco.iarc.fr/.
-
- Evans M., Bonomo P., Chan P. C., et al., “Post‐Operative Radiotherapy for Oral Cavity Squamous Cell Carcinoma: Review of the Data Guiding the Selection and the Delineation of Post‐Operative Target Volumes,” Radiotherapy and Oncology 207 (2025): 110880. - PubMed
-
- Batsakis J. G., “Nerves and Neurotropic Carcinomas,” Annals of Otology, Rhinology, and Laryngology 94, no. 4 Pt 1 (1985): 426–427. - PubMed
MeSH terms
LinkOut - more resources
Full Text Sources
Medical