Journal Information
Vol. 88. Issue 3.
Pages 293-295 (July - September 2023)
Download PDF
More article options
Vol. 88. Issue 3.
Pages 293-295 (July - September 2023)
Scientific letter
Full text access
Surgical approach to anorectal melanoma: A case report
Abordaje quirúrgico del melanoma anorrectal, a propósito de un caso
M. Philippe-Poncea,
Corresponding author

Corresponding author at: Avenida 25 Poniente 1301, Colonia Volcanes, C.P. 72410, Puebla, Mexico. Tel.: 222239 2507.
, M.A. Vela-Ramosa, M.A. Jiménez-Duránb, C.Z. Díaz-Barrientosa, R. Zayas-Borqueza
a Servicio de Cirugía General, Hospital Universitario de Puebla, Puebla, Puebla, Mexico
b Medicina General, Puebla, Puebla, Mexico
This item has received
Article information
Full Text
Download PDF
Figures (2)
Full Text

Mucosal melanomas are rare tumors and account for 1.3% of all cases of melanoma.1 Anorectal melanoma (ARM) makes up 1% of the cancers of the anal canal and is the third most common melanoma, after the cutaneous and ocular types. The anal canal is the most common site for primary gastrointestinal melanoma.2,3 ARM is more frequent in women, with a female-to-male ratio of 1.5:1 and mainly affects advanced age patients.4 The disease tends to go undetected until symptoms present, which can include rectal bleeding, anal pain, pruritus, tenesmus, change in bowel habit, or the presence of an anorectal mass.3,5 Palpable inguinal lymphadenopathy, other regional adenopathy, or synchronous distant metastasis present less frequently.5

Abdominoperineal resection (APR) used to be considered the best treatment option, but more recent evidence suggests that survival is the same with local excision (LE), which results in less perioperative morbidity.6 The use of radiotherapy, chemotherapy, or adjuvant immunotherapy has been a subject of debate.2

A 63-year-old woman had a medical history of diabetes and high blood pressure, for which she was receiving treatment. Six months earlier she began to have scant rectal bleeding after a bowel movement that progressively increased. Pharmacologic treatment afforded little improvement. She arrived at the emergency department due to abundant rectal bleeding. Upon admission, an 8cm prolapsed tumor, protruding through the anus, with two 1cm flaps, was identified (Fig. 1A). Laboratory work-up reported leukocytes 13.2 cell/mm3, hemoglobin 9.8g/dl, hematocrit 29%, glucose 140mg/dl, BUN 40mg/dl, urea 85.6mg/dl, and creatinine 2.0mg/dl. The diagnosis was probable rectal cancer. Colonoscopy was performed, revealing a 6cm dark, friable tumor, and a computed tomography (CT) scan showed no metastasis. PET/CT imaging was not carried out because that test is not available at our institution.

Figure 1.

A. Anal tumor. B. Abdominoperineal resection specimen.


Due to the presence of active bleeding and prolapse that would hinder local resection, APR was performed, revealing, 2cm from the anus, a 7x5cm soft, dark, friable prolapsed tumor, with active bleeding, protruding from the rectum (Fig. 1B). The histopathologic analysis reported a 4x3.5cm anorectal melanoma that invaded the muscle wall, without reaching the radial margin; positive lymphovascular invasion; the resection of 11 lymph nodes (2 with metastasis); and neoplasia-free margins (Fig. 2). Immunohistochemistry revealed positive HMB-45 and positive Melan-A. The patient’s postoperative period was satisfactory, she was discharged, and is currently undergoing chemotherapy.

Figure 2.

A. Mucosa in the anal canal with neoplastic cell infiltration at the junction. B. Connective tissue with melanin pigmentation that extends in a lentiform manner.


ARM is a lethal disease, with a median survival of 15 to 21 months.1 The majority of lesions appear to arise at or below the level of the dentate line; at least 25% are amelanotic.3

Ford et al.1 found no significant differences in general survival, with respect to the surgical focus, with a 20.2% survival rate for APR, compared with the 17.3% survival rate of LE (p=0.31). Iddings et al.5 found a similar median general survival of 18 and 16 months, after transanal excision and APR, respectively. Five-year survival was similar in the two groups: 16.8% for APR versus 19.3% for transanal resection.

Nilsson and Ragnarsson-Olding studied a total of 251 patients diagnosed with anorectal melanoma, describing a 5-year survival rate of 11.2%. There was no significant difference, regarding the median survival in patients treated with APR or LE (11 vs. 14 months), and the 5-year survival rate was 7 vs. 15%, respectively (p=0.0984). The risk for recurrence was significantly lower when an R0 resection was achieved (p<0.001), albeit the recurrence risk after APR and LE was similar (p=0.106).7

The majority of studies show a higher local control rate for patients that have undergone APR, but no survival benefit, when compared with LE. When surgery is indicated in cases of melanoma located in the anorectal junction, APR is likely required, given that LE is probably not possible in such cases. Likewise, APR can be applied to lesions within the anal canal itself, whereas those at the anal verge are benefited more by LE. APR has the advantage of controlling lymphatic spread and creating wider excision margins, resulting in a lower local recurrence rate. On the other hand, LE offers patients an apparently equivalent symptom control, in addition to the opportunity for cure, with significantly less morbidity and the avoidance of a permanent colostomy.3

Current scientific evidence indicates that radical surgery does not improve survival in patients with ARM, and so APR should only be performed in patients in whom LE is not technically possible. LE can be carried out if it results in R0 resection, i.e., an adequate resection margin.4

The planning of surgery after thorough clinical and radiologic evaluations, including magnetic resonance imaging of the pelvis and whole-body PET/CT, can aid in defining the appropriate surgical approach for achieving R0 resection.7 The goal of primary ARM resection should be to obtain negative margins, while maintaining sphincter function.5

Ethical considerations

The authors declare that they have met all ethical responsibilities regarding data protection, the right to privacy, informed consent.

Authorization by the ethics committee of the hospital was not necessary given that patient anonymity was never violated nor were any experimental procedures conducted that could put patient integrity at risk.

The authors declare that this article contains no personal information that could identify the patients.

Financial disclosure

No specific grants were received from public sector agencies, the business sector, or non-profit organizations in relation to this article.

Conflict of interest

The authors declare that there is no conflict of interest.

M.M. Ford, R.M. Kauffmann, T.M. Geiger, et al.
Resection for anal melanoma: Is there an optimal approach?.
J. Naqvi, A. Lee, A. Lederman, et al.
Patterns of care and survival outcomes in the treatment of anal melanoma.
J Gastrointest Cancer, 51 (2020), pp. 211-216
A. McBrearty, D. Porter, K. McCallion.
Anal melanoma: A general surgical experience.
J Clin Case Rep, 5 (2015), pp. 493
A. Reina, J. Errasti, E. Espín.
Melanoma anorrectal. Revisión de conjunto.
D.M. Iddings, A.J. Fleisig, S.L. Chen, et al.
Practice patterns and outcomes for anorectal melanoma in the USA, reviewing three decades of treatment: is more extensive surgical resection beneficial in all patients?.
Ann Surg Oncol, 17 (2010), pp. 40-44
G. Malaguarnera, R. Madeddu, V.E. Catania, et al.
Anorectal mucosal melanoma.
Oncotarget, 9 (2018), pp. 8785-8800
P.J. Nilsson, B.K. Ragnarsson-Olding.
Importance of clear resection margins in anorectal malignant melanoma.
Br J Surg, 97 (2010), pp. 98-103

Please cite this article as: Philippe-Ponce M, Vela-Ramos MA, Jiménez-Durán MA, Díaz-Barrientos CZ, Zayas-Borquez R. Abordaje quirúrgico del melanoma anorrectal, a propósito de un caso. Rev Gastroenterol Méx. 2023;88:293–295.

Copyright © 2023. Asociación Mexicana de Gastroenterología
Revista de Gastroenterología de México
Article options
es en
Política de cookies Cookies policy
Utilizamos cookies propias y de terceros para mejorar nuestros servicios y mostrarle publicidad relacionada con sus preferencias mediante el análisis de sus hábitos de navegación. Si continua navegando, consideramos que acepta su uso. Puede cambiar la configuración u obtener más información aquí. To improve our services and products, we use "cookies" (own or third parties authorized) to show advertising related to client preferences through the analyses of navigation customer behavior. Continuing navigation will be considered as acceptance of this use. You can change the settings or obtain more information by clicking here.