Definitive radiotherapy vs. postoperative radiotherapy for lower gingival carcinomas of the mandible : A single-center report about outcome and toxicity

Frequency of osteoradionecrosis of the lower jaw after radiotherapy of oral cancer patients correlated with dosimetric parameters and other risk factors

Objectives

Osteoradionecrosis (ORN) of the lower jaw is a serious late complication after radiotherapy in patients with oral cavity cancer. The aim of this study is to generate more insight into which patient- and treatment-related factors are associated with the development of ORN in oral cavity cancer patients undergoing postoperative radiotherapy.

Material and methods

Retrospective evaluation and comparison of 44 patients with ORN (event group 1) matched according to 45 patients without ORN (control group 2) who received postoperative radiotherapy of oral cavity squamous cell carcinoma at our institution between 2012 and 2020. Dosimetric factors that favor the occurrence of ORN should be detected. The cumulative occurrence rate of ORN was calculated according to the Kaplan–Meier method and analyzed by Cox regression and log-rank test.

Results

The median time to develop ORN was 18 months (3–93 months) after radiotherapy. Dental status before radiotherapy (RT) treatment (HR 4.5; 1.8–11.5) and dosimetric parameters including Dmean > 45 Gy (HR 2.4; 1.0–5.7), Dmax > 60 Gy (HR 1.3; 1.1–2.8) and planning target volume (PTV) proportion > 40% intersection with the lower jaw (HR 1.1; 1.0–1.1) were significantly associated with ORN.

Conclusion

The results of this retrospective study reveal that oral cavity cancer patients who underwent pre-RT dental surgery as well as dosimetric parameters using Dmax > 60 Gy, higher mean doses > 45 Gy and more than 40% PTV intersection with the lower jaw bone are independent risk factors for ORN. These findings can assist in the management of patients undergoing RT for head and neck cancer regarding ORN prevention.

Clinical relevance

Poor oral hygiene and desolate dental status as well as high radiation doses to the mandibular bone significantly increase the risk of developing osteoradionecrosis. Before irradiating a patient with oral cavity cancer, an appointment with the dentist should be made and teeth sanitized if necessary. Likewise, maximum radiation doses to the lower jaw should be minimized.

Definitive radiotherapy for squamous cell carcinoma of the oral cavity: a single-institution experience

Background

Surgery is standard of care for oral cavity cancer (OCC). We provide a single-institution experience using definitive radiotherapy (RT) with or without concurrent systemic therapy for primary unresectable OCC.

Patients and methods

We retrospectively examined 49 patients with non-metastatic primary unresectable OCC treated with definitive RT between 2000 and 2019. The majority of patients (63.3%) were treated with definitive chemoradiotherapy while 26.5% were given single-agent cetuximab weekly simultaneous to definitive RT. Five patients were treated with definitive RT alone because of limited disease and no nodal involvement.

Results

Median follow-up was 73 months (range, 6–236 months), median progression free survival (PFS) was 42 months (range, 2–157 months), median local disease-free survival (LDFS) was 44 months (range, 2–157 months) and median overall survival (OS) from the time of RT initiation was 52 months (range, 5–236 months). There were 65.3% locoregional failures, 84.4% local and 15.6% distant metastasis. The majority of patients with local failure presented with American Joint Committee on Cancer (AJCC) Stage III–IV disease (59.2%). The 5-year Kaplan-Meier estimates for OS (III–IV vs. I–II) was 22.8% vs. 54.2 % (p = 0.03, HR 2.090, 1.1–4.2). Patients who were treated with systemic therapy had a significant better 5-year overall survival compared to those with RT alone (43.9% vs. 23.1%, p = 0.05, 1.0–4.1). RT with doses less than 70 Gy (p = 0.046, HR 2.1 (1.0–4.5) was associated with worse overall survival. Mucositis was the most common ≥ grade 3 acute toxicity and occurred in 19 patients (39%). Incidences of chronic toxicities were loss of taste, trismus, osteoradionecrosis and xerostomia.

Conclusions

Definitive RT with or without concurrent systemic agents in patients with unresectable OCC resulted in an eloquent rate of locoregional control and good overall survival rates and is currently the best available treatment option in this patient collective.

Challenging management of gingival squamous cell carcinoma: a 10 years single-center retrospective study on Northern-Italian patients

Background

Aim of this study was to describe the outcome of patients with gingival squamous cell carcinoma (GSCC), and to recognize aspects affecting clinical course and to consider survival rate.

Material and Methods

The case records of patients, over a 10-year period, were retrospectively examined. Differences in distribution of the potential risk factors by prognosis were investigated through non-parametrical tests (Wilcoxon Rank-Sum and Fisher’s Exact). Survival curves for age, therapy and stage were built by the Kaplan-Meier method and compared with Log-Rank test.

Results

79 patients were analysed. Significant increase in mortality for patients older than 77 and for those with advanced stages was found. Cumulative survival rate 5 years after the diagnosis was 43%, while at 10 years was of 11%.

Conclusions

With a statistical relationship between age and tumour stage with survival rates, and 70% of GSCC cases identified as stage IV, early GSCC diagnosis remains challenging.

Key words:Gingival cancer, clinical appearance, treatment, retrospective study.

Impact of superselective intra-arterial and systemic chemoradiotherapy for gingival carcinoma; analysis of treatment outcomes and prognostic factors

Background

We compared outcomes and toxicities between concurrent retrograde super-selective intra-arterial chemoradiotherapy (IACRT) and concurrent systemic chemoradiotherapy (SCRT) for gingival carcinoma (GC).

Methods

We included 84 consecutive patients who were treated for non-metastatic GC ≥ stage III, from 2006 to 2018, in this retrospective analysis (IACRT group: n = 66; SCRT group: n = 18).

Results

The median follow-up time was 24 (range: 1–124) months. The median prescribed dose was 60 (6–70.2) Gy (IACRT: 60 Gy; SCRT: 69 Gy). There were significant differences between the two groups in terms of 3-year overall survival (OS; IACRT: 78.8, 95% confidence interval [CI]: 66.0–87.6; SCRT: 50.4, 95% CI: 27.6–73.0; P = 0.039), progression-free survival (PFS; IACRT: 75.6, 95% CI: 62.7–85.2; SCRT: 42.0, 95% CI: 17.7–70.9; P = 0.028) and local control rates (LC; IACRT: 77.2, 95% CI: 64.2–86.4; SCRT: 42.0, 95% CI: 17.7–70.9; P = 0.015). In univariate analysis, age ≥ 65 years, decreased performance status (PS) and SCRT were significantly associated with worse outcomes (P < 0.05). In multivariate analysis, age ≥ 65 years, clinical stage IV, and SCRT were significantly correlated with a poor OS rate (P < 0.05). Patients with poorer PS had a significantly worse PFS rate. Regarding acute toxicity, 22 IACRT patients had grade 4 lymphopenia, and osteoradionecrosis was the most common late toxicity in both groups.

Conclusions

This is the first report to compare outcomes from IACRT and SCRT among patients with GC. ALL therapy related toxicities were manageable. IACRT is an effective and safe treatment for GC.