Electron beam radiotherapy for the management of squamous cell carcinoma of the anal margin
DOI:
https://doi.org/10.2340/1651-226X.2024.40199Keywords:
Squamous cell carcinoma of the anal margin, anal cancer, radiotherapy, electron beam radiotherapyAbstract
Purpose and objective: Squamous cell carcinoma of the anal margin (SCCAM) is an uncommon lesion that comprises one-third to a quarter of all anal squamous cell carcinoma. Treatment involves surgery or exclusive radiotherapy for small tumours, whereas the preferred treatment for larger tumours is chemoradiotherapy. In our department, selected patients with SCCAM are treated with electron beam radiotherapy using one perineal field. The present study evaluates this strategy.
Material and methods: All consecutive patients with SCCAM and treated with electron beam radiotherapy from 2012 to 2022 were included. Data were retrospectively extracted from the medical records and analysed descriptively. Local control (LC) and overall survival (OS) were analysed using Kaplan-Meier statistics.
Results: Forty patients were evaluated. Primary radiotherapy was delivered in 35 (87.5%) patients. Five (12.5%) patients had postoperative radiotherapy. Median prescription dose was 60.0 (range 45.0–60.2) Gy in 28 (range 10–30) fractions delivered with 8 (range 4–18) MeV using a standard circular aperture and bolus.
At a median follow-up of 73 (range 9–135) months, 7 (17.5%) patients were diagnosed with local recurrences. The 5-year LC rate was 84.3% (95% CI: 71.4%–97.2%). Analysis of LC according to T-stage revealed a 5-year LC of 100% (95% CI: 100%–100%) in T1 tumours compared to 57.0% (95% CI: 27.4%–86.6%) in T2 tumours (p < 0.001). 5-year OS was 91.6% (95% CI: 83.0%–100%). Late grade 3 toxicity included ulceration in the skin and subcutis in 2 (5.0%) patients.
Intepretation: Electron beam radiotherapy enables the delivery of ‘eye-guided’ radiotherapy directly to the tumour. LC is good in patients with T1 tumours. Patients with T2 tumours have less satisfactory LC and should be treated with chemoradiotherapy.
Electron beam radiotherapy enables the delivery of “eye-guided” RT directly to the tumour. LC is excellent in patients with T1 tumours. Patients with T2 tumours have less satisfactory LC and should be treated with chemoradiotherapy.
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References
Wietfeldt ED, Thiele J. Malignancies of the anal margin and perianal skin. Clin Colon Rectal Surg. 2009;22(2):127–35.
https://doi.org/10.1055/s-0029-1223845 DOI: https://doi.org/10.1055/s-0029-1223845
Papillon J, Chassard JL. Respective roles of radiotherapy and surgery in the management of epidermoid carcinoma of the anal margin. Series of 57 patients. Dis Colon Rectum. 1992;35(5):422–9.
https://doi.org/10.1007/BF02049397 DOI: https://doi.org/10.1007/BF02049397
Gracie J, Fortune ECt, Morris CG, Leach DF, 3rd, Mendenhall WM. Radiation treatment for cancer of the anal margin. Am J Clin Oncol. 2023;46(4):167–71.
https://doi.org/10.1097/COC.0000000000000986 DOI: https://doi.org/10.1097/COC.0000000000000986
Balamucki CJ, Zlotecki RA, Rout WR, Newlin HE, Morris CG, Kirwan JM, et al. Squamous cell carcinoma of the anal margin: the university of Florida experience. Am J Clin Oncol. 2011;34(4):406–10.
https://doi.org/10.1097/COC.0b013e3181e9c0c0 DOI: https://doi.org/10.1097/COC.0b013e3181e9c0c0
Maccabe TA, Parwaiz I, Longman RJ, Thomas MG, Messenger DE. Outcomes following local excision of early anal squamous cell carcinomas of the anal canal and perianal margin. Colorectal Dis. 2021;23(3):689–97.
https://doi.org/10.1111/codi.15424 DOI: https://doi.org/10.1111/codi.15424
Nilsson MP, Undseth C, Albertsson P, Eidem M, Havelund BM, Johannsson J, et al. Nordic anal cancer (NOAC) group consensus guidelines for risk-adapted delineation of the elective clinical target volume in anal cancer. Acta Oncol. 2023;62(8):897–906.
https://doi.org/10.1080/0284186X.2023.2240490 DOI: https://doi.org/10.1080/0284186X.2023.2240490
Rao S, Guren MG, Khan K, Brown G, Renehan AG, Steigen SE, et al. Anal cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up(☆). Ann Oncol. 2021;32(9):1087–100.
https://doi.org/10.1016/j.annonc.2021.06.015 DOI: https://doi.org/10.1016/j.annonc.2021.06.015
Khanfir K, Ozsahin M, Bieri S, Cavuto C, Mirimanoff RO, Zouhair A. Patterns of failure and outcome in patients with carcinoma of the anal margin. Ann Surg Oncol. 2008;15(4):1092–8.
https://doi.org/10.1245/s10434-007-9794-9 DOI: https://doi.org/10.1245/s10434-007-9794-9
Franco PSE, Johnsson A, Riechelmann R, Guren MG, Das P, Rao S, et al. A machine-learning-based bibliometric analysis of the scientific literature on anal cancer. Cancers (Basel). 2022;14(7):1697.
https://doi.org/10.3390/cancers14071697 DOI: https://doi.org/10.3390/cancers14071697
Newlin HE, Zlotecki RA, Morris CG, Hochwald SN, Riggs CE, Mendenhall WM. Squamous cell carcinoma of the anal margin. J Surg Oncol. 2004;86(2):55–62; discussion 3.
https://doi.org/10.1002/jso.20054 DOI: https://doi.org/10.1002/jso.20054
Chai CY, Tran Cao HS, Awad S, Massarweh NN. Management of stage I squamous cell carcinoma of the anal canal. JAMA Surg. 2018;153(3):209–15.
https://doi.org/10.1001/jamasurg.2017.3151 DOI: https://doi.org/10.1001/jamasurg.2017.3151
Chapet O, Gerard JP, Mornex F, Goncalves-Tavan S, Ardiet JM, D’Hombres A, et al. Prognostic factors of squamous cell carcinoma of the anal margin treated by radiotherapy: the Lyon experience. Int J Colorectal Dis. 2007;22(2):191–9.
https://doi.org/10.1007/s00384-006-0114-9 DOI: https://doi.org/10.1007/s00384-006-0114-9
Touboul E, Schlienger M, Buffat L, Lefkopoulos D, Yao XG, Parc R, et al. Epidermoid carcinoma of the anal margin: 17 cases treated with curative-intent radiation therapy. Radiother Oncol. 1995;34(3):195–202.
https://doi.org/10.1016/0167-8140(95)01522-I DOI: https://doi.org/10.1016/0167-8140(95)01522-I
Bieri S, Allal AS, Kurtz JM. Sphincter-conserving treatment of carcinomas of the anal margin. Acta Oncol. 2001;40(1):29–33.
https://doi.org/10.1080/028418601750071019 DOI: https://doi.org/10.1080/028418601750071019
Peiffert D, Bey P, Pernot M, Hoffstetter S, Marchal C, Beckendorf V, et al. Conservative treatment by irradiation of epidermoid carcinomas of the anal margin. Int J Radiat Oncol Biol Phys. 1997;39(1):
57–66.
https://doi.org/10.1016/S0360-3016(97)00316-7 DOI: https://doi.org/10.1016/S0360-3016(97)00316-7
Myerson RJ, Outlaw ED, Chang A, Birnbaum EH, Fleshman JW, Grigsby PW, et al. Radiotherapy for epidermoid carcinoma of the anus: thirty years’ experience. Int J Radiat Oncol Biol Phys. 2009;75(2):428–35.
https://doi.org/10.1016/j.ijrobp.2008.11.047 DOI: https://doi.org/10.1016/j.ijrobp.2008.11.047
Spinelli L MS, Solla SD, Vigna Taglianti R, Olivero F, et al. Nodal elective volume selection and definition during radiation therapy for early stage (T1–T2 N0 M0) perianal squamous cell carcinoma: a narrative clinical review and critical appraisal. Cancers (Basel). 2023;15(24):5833.
https://doi.org/10.3390/cancers15245833 DOI: https://doi.org/10.3390/cancers15245833
UKCCCR Anal Cancer Trial Working Party. Epidermoid anal cancer: results from the UKCCCR randomised trial of radiotherapy alone versus radiotherapy, 5-fluorouracil, and mitomycin. UK Co-ordinating Committee on Cancer Research. Lancet. 1996;348(9034):1049–54.
https://doi.org/10.1016/S0140-6736(96)03409-5 DOI: https://doi.org/10.1016/S0140-6736(96)03409-5
Bartelink H, Roelofsen F, Eschwege F, Rougier P, Bosset JF, Gonzalez DG, et al. Concomitant radiotherapy and chemotherapy is superior to radiotherapy alone in the treatment of locally advanced anal cancer: results of a phase III randomized trial of the European Organization for Research and Treatment of Cancer Radiotherapy and Gastrointestinal Cooperative Groups. J Clin Oncol. 1997;15(5):
2040–9.
https://doi.org/10.1200/JCO.1997.15.5.2040 DOI: https://doi.org/10.1200/JCO.1997.15.5.2040
Northover J, Glynne-Jones R, Sebag-Montefiore D, James R, Meadows H, Wan S, et al. Chemoradiation for the treatment of epidermoid anal cancer: 13-year follow-up of the first randomised UKCCCR Anal Cancer Trial (ACT I).
Br J Cancer. 2010;102(7):1123–8.
https://doi.org/10.1038/sj.bjc.6605605 DOI: https://doi.org/10.1038/sj.bjc.6605605
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