Adjuvant brachytherapy for oral squamous cell carcinomas: a single-center experience comparing low-dose and pulsed-dose-rate techniques.

OBJECTIVE: This study aims to assess the outcomes of adjuvant interstitial brachytherapy (BT) to the tumor bed for oral cavity squamous cell carcinoma (SCC), and to compare the oncological outcomes and toxicity profile of low-dose-rate (LDR) and pulsed-dose-rate (PDR) BT. DESIGN: This retrospective single-center study included all patients who underwent postoperative LDR- or PDR-BT to the tumor bed as the sole adjuvant treatment for an oral tongue or floor of the mouth SCC between January 2000 and December 2020. RESULTS: A total of 79 patients were eligible for this study. The cohort was divided into an LDR group (n = 38) and a PDR group (n = 41). The median time interval between surgery and brachytherapy was 55 days. Median delivered total dose was 55 Gy and median hospital stay was 5 days. Five patients (8.3%) experienced grade 3-4 early toxicity, 2 in the LDR group and 3 in the PDR group. Late toxicities were present in 28 patients (44.4%) and were dominated by grade 1-2 residual pain and dysesthesia, without a statistical difference between the groups. After a median follow-up of 65.1 months, 5­year local control (LC), disease-free survival (DFS), and overall survival (OS) for the whole cohort were 76.3% (95% CI = 63.4-85.1), 61.6% (95% CI = 49.0-72.0), and 71.4% (95% CI = 58.6-80.8), respectively. CONCLUSION: Adjuvant BT after excision of oral cavity SCC provides satisfactory oncological outcomes along with good tolerance. In our study, PDR-BT showed similar oncological and functional results to LDR-BT in this indication.

Osteoradionecrosis After Mandibulotomy and Marginal Mandibulectomy in Patients With Oral Cancer.

Objectives Osteoradionecrosis is one of the most severe complications in patients with head and neck cancer, which is characterized by persistent exposed and devitalized bone without proper healing after radiation. The extent to which mandibulotomy and marginal mandibulectomy influence the occurrence of osteoradionecrosis remains unclear. This study evaluated the incidence and risk factors for developing osteoradionecrosis of the mandible after oral cancer treatments. Methods A retrospective study was performed to analyze medical records of patients who underwent surgery and postoperative radiotherapy for oral cancers from 2009 to 2019 at a tertiary care hospital. Patient characteristics, incidence, and risk factors for developing osteoradionecrosis were reviewed. Comparisons between continuous and categorical data were performed using t-test and Chi-squared test. Cox regression analysis was used to assess the association between factors and the development of osteoradionecrosis. Results Among the 61 patients included in the study, osteoradionecrosis of the mandible occurred in 9 of 32 (28.1%) patients who underwent mandibular surgery during oral cancer resection (marginal mandibulectomy and/or mandibulotomy) and 2 of 29 (6.9%) patients without mandibular surgery. The development of osteoradionecrosis was significantly associated with performing mandibular surgery (hazard ratio 4.64, 95% confidence interval: 1.002, 21.5) and HIV infection (hazard ratio 8.53, 95% confidence interval: 2.2, 33.3). In the subgroup analysis of mandibular surgery, the development of osteoradionecrosis significantly increased in patients undergoing mandibulotomy (hazard ratio 6.62, 95% confidence interval: 1.3, 34.8) but not in patients undergoing marginal mandibulectomy (hazard ratio 3.56, 95% confidence interval: 0.6, 22.0). The analysis also showed that concurrent chemoradiation, radiation doses ≥ 60 Gy, and smoking were potential risk factors for the development of osteoradionecrosis, but none of these factors were statistically significant. Conclusion Our findings suggest that mandibular surgery is a significant risk factor for the development of osteoradionecrosis in patients with oral cancer. Further studies including larger population sizes are required to verify these findings.

Retrograde Migration of an Au-198 Grain to the Submandibular Gland Post Brachytherapy Treatment of Floor of Mouth Cancer.

At our institution, radiation oncologists routinely treat early-stage oral cancer with low-dose-rate brachytherapy (LDR-BRT) using Au-198 grains. In this report, we show a unique case of a patient with a gold grain located within the submandibular gland, found incidentally during follow-up after LDR-BRT for floor of mouth cancer. One month after the implant, he showed sialadenitis-like symptoms, but the pain resolved two months later. All the grains were detected around the anterior sublingual area by computed tomography (CT) four months after the implant. Unexpectedly, 11 months after the implant, CT revealed that a grain was located in an intraglandular site of the submandibular gland. This finding clearly demonstrates that the grain entered Wharton's duct and retrogradely migrated to the submandibular gland through the duct. As a mechanism of the calculus formation within Wharton's duct, retrograde migration of foreign bodies to the inside of the duct has been proposed. Our incidental finding after LDR-BRT highlights the need for monitoring post-LDR-BRT using Au-198 grains for the treatment of floor of mouth cancer and sheds additional light on retrograde theory within Wharton's duct.

Application of vascularized mucosal flap for early-medium-term tongue cancer and floor of mouth cancer defect repair: a preliminary study.

OBJECTIVES: This study aimed to assess the efficacy and safety of facial artery musculomucosal (FAMM) flap for small-medium tongue or floor of mouth defects caused by surgical resection of early-medium stage tongue or floor of mouth cancer. METHODS: A retrospective cohort study was conducted and included patients with early-medium stage tongue or floor of mouth cancer and reconstructed by FAMM flap or traditional free or axial flaps. Demographic data and surgery-related data were collected. Patients were followed up for 6 months and evaluated with satisfaction, maximal mouth opening, satisfactory contour and speech, and oral intake function at months 3 and 6. RESULTS: Forty-five patients were included, with 15 in the FAMM group and 30 in the flap group. All patients finished 3 months follow-up, and 1 in each group was lost to follow-up at month 6. All followed-up patients had no recurrence or metastasis. The FAMM group had a significantly shorter surgical time than the flap group (P<0.05). The flap group had significantly more donor sites that were uncomfortable compared with the FAMM group (P<0.05). There was no statistical significance on satisfaction, but the FAMM group had better outcomes on contour, speech, and oral intake function at month 6 than the flap group (P<0.05). The FAMM group had smaller maximal mouth opening than the flap group (P<0.05) at month 3 but equivalent maximal mouth opening at month 6 (P>0.05). CONCLUSIONS: FAMM flap has some advantages for small-medium tongue or floor of mouth defects caused by surgical resection of early-medium stage tongue or floor of mouth cancer, and it could be an ideal choice for clinical application.

Clinicopathologic Characteristics and Survival Outcomes in Floor of Mouth Squamous Cell Carcinoma: A Population-Based Study.

Objective To describe the determinants of survival for patients with floor of mouth (FOM) squamous cell carcinoma (SCC) from 1973 to 2013 with the SEER database (Surveillance, Epidemiology, and End Results). Study Design and Setting Retrospective cohort study with a national database. Subjects and Methods The SEER registry was utilized to calculate survival trends for patients with FOM SCC between 1973 and 2013. Patient data were analyzed with respect to age, sex, race, primary site, stage at presentation, tumor size, grade, and treatment modalities (surgery and radiotherapy). Overall survival (OS) and disease-specific survival (DSS) were calculated. Results A total of 14,010 FOM SCC cases were identified. The cohort was 69.5% male, and the median age at diagnosis was 62 years. Forty-six percent of cases were treated with surgery, while 14% received radiotherapy. Kaplan-Meier analysis demonstrated OS and DSS of 39% and 59% at 5 years, respectively. Multivariate analysis showed that age, grade, stage, size, and surgery were determinants for OS and DSS (all P < .05). For early- and advanced-stage cancers, age, grade, size, and surgery predicted OS and DSS, while radiotherapy was a predictor of OS and DSS in advanced-stage tumors only (all P < .05). Conclusion To our knowledge, this study is the largest to date investigating prognostic factors for survival of patients diagnosed with FOM SCC. Determinants of survival include age, grade, stage, size, and surgery. Surgery appears to play a critical role in the management of these tumors.