Impact of Overall Treatment Time on Local Control of Anal Cancer Treated with Radiochemotherapy

Abstract

Between 1987 and 2000, 111 patients with epidermoid anal cancer (T1–T4 Nx M0) were assigned to primary simultaneous radiochemotherapy (RCT) with a radiation dose of 45 Gy, performed either as a split course with 2-Gy single fractions (schedule A, 1987–1996, n = 65 patients) or continuously with fractions of 1.8 Gy (schedule B, 1996–2000; n = 38 patients). The chemotherapy consisted of continuous infusions of 5-fluorouracil (5-FU; 800/1,000 mg/m²/day, on 4/5 consecutive days, during weeks 1 and 5) together with one (schedule A) or two (schedule B) short infusions of mitomycin C (10 mg/m²) during the first course of 5-FU. Associations between clinical outcome and various prognostic factors were assessed in 103 patients who completed these schedules. For both patient groups combined, 5-year local control rate was 67% and 5-year survival rate 71%. Advanced tumor stage, size, and nodal status significantly decreased the 5-year local control rate as well as the overall treatment time (OTT) >41 days (58% for OTT >41 days vs. 79% for OTT ≤41 days; p = 0.04). However, we did not find a correlation with the prescribed radiotherapy schedule (A or B). In conclusion, in patients with anal carcinomas treated with RCT with a radiation dose of 45 Gy, the predominant determinant of local control is the resulting OTT and not the administration schedule (split course or continuous radiotherapy).

Clinical outcome in patients treated with simultaneous integrated boost – intensity modulated radiation therapy (SIB-IMRT) with and without concurrent chemotherapy for squamous cell carcinoma of the anal canal

“…The omission of a treatment gap in our series is probably the most important factor responsible for the better LRC and CCR compared with these two older trials. The negative impact of increased gap duration is well recognized [4][5][6][7][8]. The SIB-IMRT technique used in our series allows an even shorter treatment gap and further reduces the OTT, which has the theoretical advantage of improving local control.…”

“…The former was attributed to, among other factors, the use of a long treatment gap [i.e. a rest period of six weeks between initial CRT and radiotherapy (RT) boost] [4][5][6][7][8], whereas the latter is probably due to the use of two large opposed anterior-posterior fields or a three-field technique [1,2].…”

Treatment of carcinoma of the anal canal at Groote Schuur Hospital

“…15,16 We have changed our treatment protocol to a continuous regimen of 50.00 Gy in 2.00 Gy fractions using 3D conformal radiotherapy where possible.…”

Análise retrospectiva das neoplasias de ânus em pacientes atendidos no HC-FMRP-USP de 1979 a 2004 e revisão da literatura

“…Mesmo para grandes tumores, maiores que 5cm, que apresentam menor resposta à terapia combinada (cerca de 50 a 75%), devemos, inicialmente, tentar a terapia combinada, proporcionando ao paciente uma chance de cura, com boa sobrevida, sem a necessidade de colostomia definitiva 19 . Entretanto, os tumores em estágio avançado, com doença nodal inguinal e grande tamanho tumoral (> 5 cm) apresentaram queda significativa no controle local da doença em 5 anos e diminuição na taxa de sobrevida 37,39 . Entretanto, alguns poucos trabalhos, tais como Tobulou e colaboradores 7 , afirmam que a radioterapia isolada desde 1980 é a terapia de escolha (com intenção curativa) para os casos de CEC de canal anal na França.…”