Lucas Gomes Sapienza1, Matthew Stephen Ning2, Senzo Taguchi3, Vinícius Fernando Calsavara4, Antônio Cássio de Assis Pellizzon5, Maria José Leite Gomes6, Luiz Paulo Kowalski7, Glauco Baiocchi8. 1. Department of Radiation Oncology, A.C. Camargo Cancer Center, São Paulo, SP, Brazil; Department of Radiation Oncology, Hospital Central do Exército do Rio de Janeiro (HCE-RJ), Rio de Janeiro, RJ, Brazil. Electronic address: lucasgsapienza@gmail.com. 2. Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA. 3. Department of Radiation Oncology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan. 4. Department of Statistics and Epidemiology, AC Camargo Cancer Center, São Paulo, SP, Brazil. Electronic address: vinicius.calsavara@accamargo.org.br. 5. Department of Radiation Oncology, A.C. Camargo Cancer Center, São Paulo, SP, Brazil. 6. Department of Radiation Oncology, Hospital Federal dos Servidores do Estado (HFSE-RJ), Rio de Janeiro, RJ, Brazil. 7. Department of Head and Neck Surgery, A.C. Camargo Cancer Center, São Paulo, SP, Brazil. 8. Department of Gynecologic Oncology, A.C. Camargo Cancer Center, São Paulo, SP, Brazil.
Abstract
OBJECTIVES: To perform a systematic review of 1762 patients to comprehensively assess the benefit of altered-fractionation radiotherapy (ART) in early stage glottic carcinoma (ESGC). MATERIALS AND METHODS: Studies were identified in PubMed and EMBASE. Inclusion criteria were: (1) diagnosis of squamous cell ESGC (Tis, T1, T2); (2) ART versus conventionally-fractionationated radiotherapy (CRT); and (3) provision of number of local recurrence events and total numbers per fractionation arm. The random-effects model was fitted to estimate the pooled hazard ratio (HR). Subgroup sensitivity analyses were performed based on ART strategy (hypo- versus hyperfractionation), treatment-day reductions, machine type, tumor stage, and anterior commissure involvement. RESULTS: Eleven studies met inclusion criteria: 4 randomized controlled trials (RCTs) and 7 two-arm retrospective studies. ART was associated with 38% fewer (HR 0.62; 95% CI: 0.46-0.82, p = 0.0009) and 60% fewer (HR 0.40; 95% CI: 0.24-0.66, p = 0.0003) local failure events in pooled analyses of the RCTs and retrospective studies, respectively. Both hyperfractionation (HR 0.65; 95% CI: 0.43-0.97, p = 0.03) and hypofractionation (HR 0.55; 95% CI: 0.33-0.91, p = 0.02) strategies were superior to CRT. The benefit persisted for all treatment- and tumor-related parameters, including anterior commissure involvement, with the exception of a pooled analysis of studies with predominantly T2 (<50% T1) cases (HR 0.60, 95% CI: 0.30-1.20, p = 0.15). CONCLUSION: Both hypofractionation and hyperfractionation improve local control in ESGC, including T1 tumors and for anterior commissure involvement. However, this benefit may not persist for T2 tumors, for which alternative strategies should be considered.
OBJECTIVES: To perform a systematic review of 1762 patients to comprehensively assess the benefit of altered-fractionation radiotherapy (ART) in early stage glottic carcinoma (ESGC). MATERIALS AND METHODS: Studies were identified in PubMed and EMBASE. Inclusion criteria were: (1) diagnosis of squamous cell ESGC (Tis, T1, T2); (2) ART versus conventionally-fractionationated radiotherapy (CRT); and (3) provision of number of local recurrence events and total numbers per fractionation arm. The random-effects model was fitted to estimate the pooled hazard ratio (HR). Subgroup sensitivity analyses were performed based on ART strategy (hypo- versus hyperfractionation), treatment-day reductions, machine type, tumor stage, and anterior commissure involvement. RESULTS: Eleven studies met inclusion criteria: 4 randomized controlled trials (RCTs) and 7 two-arm retrospective studies. ART was associated with 38% fewer (HR 0.62; 95% CI: 0.46-0.82, p = 0.0009) and 60% fewer (HR 0.40; 95% CI: 0.24-0.66, p = 0.0003) local failure events in pooled analyses of the RCTs and retrospective studies, respectively. Both hyperfractionation (HR 0.65; 95% CI: 0.43-0.97, p = 0.03) and hypofractionation (HR 0.55; 95% CI: 0.33-0.91, p = 0.02) strategies were superior to CRT. The benefit persisted for all treatment- and tumor-related parameters, including anterior commissure involvement, with the exception of a pooled analysis of studies with predominantly T2 (<50% T1) cases (HR 0.60, 95% CI: 0.30-1.20, p = 0.15). CONCLUSION: Both hypofractionation and hyperfractionation improve local control in ESGC, including T1 tumors and for anterior commissure involvement. However, this benefit may not persist for T2 tumors, for which alternative strategies should be considered.