ABSTRACT
BACKGROUND: Cutaneous neurotropic melanoma (NM) of the head and neck (H&N) is prone to local relapse, possibly due to difficulties widely excising the tumor. This trial assessed radiation therapy (RT) to the primary site after local excision. METHODS: Participants from 15 international centers were randomized to observation or RT. The participants were required to have microscopically negative excision margins 5 mm wide or wider and no evidence of disease elsewhere. The primary outcome was time to local relapse. The secondary outcomes included time to any recurrence, overall survival (OS), and toxicity. RESULTS: The trial ceased prematurely due to slow recruitment and the COVID-19 pandemic. During 2009-2020, 50 participants were randomized: 23 to observation and 27 to RT. The most common NM subsites were scalp (32%), midface (22%), and lip (20%). The median depth of invasion was 5 mm, and desmoplasia observed in 69%. The median duration from randomization to last contact was 4.8 years. Four participants (8%) experienced local relapse as a first recurrence during the study period: 3 in the observation arm and 1 in the RT arm (hazard ratio [HR] 0.29; 95% confidence interval [CI] 0.03-2.76; p = 0.279). No statistically significant difference in time to any relapse or OS was observed. More than 6 months after randomization, grade 3 or greater toxicity was experienced by 10% of the participants in the observation arm and 12.5% of the participants in the RT arm of the study. CONCLUSION: Due to low accrual, the role of adjuvant RT for cutaneous NM of the H&N excised with microscopically negative margins 5 mm wide or wider remains undefined. Its routine use cannot be recommended. Local relapse might be less common than previously anticipated based on retrospective reports.
Subject(s)
Head and Neck Neoplasms , Melanoma , Neoplasm Recurrence, Local , Skin Neoplasms , Humans , Melanoma/surgery , Melanoma/pathology , Melanoma/radiotherapy , Female , Male , Middle Aged , Head and Neck Neoplasms/radiotherapy , Head and Neck Neoplasms/surgery , Head and Neck Neoplasms/pathology , Aged , Neoplasm Recurrence, Local/pathology , Survival Rate , Skin Neoplasms/pathology , Skin Neoplasms/surgery , Skin Neoplasms/radiotherapy , Radiotherapy, Adjuvant , Follow-Up Studies , Adult , Prognosis , COVID-19/epidemiology , Margins of Excision , Aged, 80 and over , SARS-CoV-2 , Melanoma, Cutaneous MalignantABSTRACT
OBJECTIVE: To determine the association of MRI features of extra-abdominal desmoid tumours (DTs) with prognosis. METHODS: MRIs for 90 patients with DT were retrospectively reviewed for imaging features associated with biological behaviour. The primary end point was progression (for lesions managed with chemotherapy, radiation therapy and observation) or recurrence (following surgery). Time to event was studied using univariate and multivariable Cox proportional hazards regression models when accounting for demographic, clinicopathological and imaging variables. Kaplan-Meier plots were used to estimate event-free rate (EFR). RESULTS: Univariate analysis revealed a significant relationship between EFR and treatment, location and compartment of origin [subcutaneous (SC), superficial fascial, intramuscular (IM) and deep fascial/intermuscular]. None of the imaging features commonly associated with biological behaviour of DTs (e.g., shape, enhancement, T2 signal etc.) or surgical margins (in surgical cases) was associated with EFR. Multivariate analysis showed that treatment modality and compartment of origin were independent predictors of EFR. Superficial and deep fascial lesions had a significantly worse EFR as a group [hazard ratio: 3.9; 95% confidence interval (CI): 1.83-8.32; p = 0.0004] than did the SC and IM lesions as a group. 5-year EFR for the fascial lesions was 18% (95% CI: 6-36%), compared with 57% (95% CI: 25-79%) for the SC and IM groups. CONCLUSION: Intramuscular or SC DTs may be associated with improved prognosis. If validated on multireader and prospective studies, these results can provide for rapid risk stratification at the time of initial MRI. ADVANCES IN KNOWLEDGE: This work has shown that imaging features commonly associated with biological activity of desmoid tumours (e.g. shape, T2 signal and enhancement) do not appear to be associated with prognosis in patients undergoing a variety of treatment modalities. The compartment of origin of the lesion, which can be determined on pre-operative MRI, was shown to be associated with prognosis and can allow for risk stratification in patients with DTs.