Anal melanoma

Surgical Management of Primary Anorectal Melanoma: Is Less More?

PURPOSE

Ano-uro-genital (AUG) Mucosal Melanoma UK guidelines recommended a less radical surgical strategy for anorectal melanoma (ARM) where possible. We report our experience of ARM consistent with that approach including clinical presentation, intervention undertaken and prognosis.

METHODS

We present a retrospective study of 15 consecutive patients with ARM surgically treated between November 2014 and April 2023. Patients were divided into the two surgery types: wide local excision (WLE, n = 9) and abdominoperineal resection (APR, n = 6). Data on demographics, diagnosis, treatment and oncological outcomes were assessed between the groups.

RESULTS

The mean age was 65.3 ± 17.4 years and 6 (40.0%) were female patients. Nine patients (60.0%) were diagnosed with stage I and six patients (40.0%) with stage II disease. R0 margins were achieved in all cases. The overall mean length of stay was lower following WLE compared to APR (2.6 ± 2.4 days versus 14.0 ± 9.8 days, p = 0.032). Two complications were observed in the WLE group compared to four complications after APR (p = 0.605). Five patients (55.5%) developed local/distant recurrence in the WLE group compared to three patients (50.0%) in the APR group (p = 0.707), with a median overall survival of 38.5 (12-83) months versus 26.5 (14-48) months, respectively.

CONCLUSIONS

Achieving clear margins by the least radical fashion may have equivalent oncological outcomes to radical surgery, potentially reducing patient morbidity and preserving function. In our experience, the surgical management of ARM consistent with the 'less is more' approach adhering to AUG guidelines has acceptable outcomes.

Anorectal Melanoma: A Rare Cause of Large Bowel Obstruction

Anorectal melanoma is a rare and aggressive malignancy with a challenging diagnosis and management. We present the case of a 69-year-old male with a history of chronic constipation and recent weight loss, who presented with symptoms suggestive of anorectal pathology. Despite initial diagnostic challenges, including an unsuccessful colonoscopy due to inadequate bowel preparation, the subsequent radiographic evaluation revealed a large bowel obstruction secondary to a protruding anorectal mass. Abdominal X-ray demonstrated significant colonic dilation while contrast-enhanced CT scan revealed a large hypodense mass protruding from the anal canal. Surgical intervention led to the excision of the mass, and histopathological examination confirmed malignant melanoma. Immunohistochemistry markers, including HMB 45, Melan A, and S100, supported the diagnosis. This case underscores the importance of considering anorectal melanoma in patients presenting with atypical anorectal symptoms, despite its rarity. Early recognition and intervention, supported by appropriate imaging modalities, are critical for optimizing patient outcomes in such cases.

Anorectal mucosal melanoma

Anorectal mucosal melanoma accounts for less than 1 % of all anorectal malignant tumors and a tendency for delayed diagnosis leads to advanced disease at presentation.1,2 Due to the rarity of the disease, there are limited prospective trials exploring the optimal treatment strategies. Generally, tumors are surgically excised, with a preference for conservative management with wide local excision. In the past decade, there have been advances with immunotherapy and other targeted therapies. Multiple clinical trials continue exploring neoadjuvant/adjuvant combination treatments in the setting of advanced or unresectable disease.

Beyond squamous cell carcinoma: MRI appearance of uncommon anal neoplasms and mimickers

Anal cancer is an uncommon malignancy. In addition to squamous cell carcinoma, there are a variety of other less common malignancies and benign pathologies that may afflict the anal canal, with which abdominal radiologists should be familiar. Abdominal radiologists should be familiar with the imaging features that can help distinguish different rare anal tumors beyond squamous cell carcinoma and that can aid in diagnosis therefore help steer management. This review discusses these uncommon pathologies with a focus on their imaging appearance, management, and prognosis.

Primary malignant melanoma of rectum: A rare case report

INTRODUCTION

Malignant melanoma of the gastrointestinal tract is an extremely rare event of which 50 % occurs in anorectal region. The lesion can easily be misdiagnosed as rectal-carcinoma, which comprises >90 % of rectal tumors and has a different treatment. The behavior of the anorectal melanoma is very aggressive and has very poor prognosis with fatal outcome.

PRESENTATION OF CASE

A 48-year-old man presented complaining of rectal bleeding of two months' duration, without any other significant history. Colonoscopy showed a polypoidal mass in the rectum that was in favor of adenocarcinoma. The microscope examination of biopsy tissue showed sheets of poorly differentiated malignant neoplasm. Immuno-histochemical (IHC) staining showed negativity of pan Cytokeratin and CD31. IHC for HMB45 showed diffuse and strong positivity in neoplastic cells, confirming the diagnosis of malignant melanoma.

CLINICAL DISCUSSION

According to a report by the National Cancer Database of the United States, primary rectal melanoma is very rare. Mucosal surface of the body is third most common site for primary melanoma after skin and eye. The first case of anorectal melanoma was reported in 1857. Histopathological examinations are gold standard for diagnosis, but histopathology examination without immunohistochemistry will misdiagnose some cases as poorly differentiated adenocarcinoma which has completely different treatment. Surgical resection has been reported as the most useful treatment option.

CONCLUSION

Malignant melanoma of the rectum is extremely rare and difficult to diagnose in low resources settings. Histopathologic examination with IHC stains can differentiate poorly differentiated adenocarcinoma from melanoma and other rare tumors of anorectal region.

Treatment outcomes and prognostic factors in 47 patients with primary anorectal malignant melanoma in the immune therapy era

PURPOSE

Primary anorectal melanoma (ARM) accounts for approximately 1.2% of all melanomas and 16.5% of all mucosal melanomas. ARM is associated with the shortest interval to disease progression and the highest rate of metastasis; however, optimal therapeutic strategies for ARM remain controversial. This study aimed to assess the ideal surgical intervention for ARM and to determine the effect of immune checkpoint inhibitors (ICI).

METHODS

We included 47 patients with ARM treated at the National Cancer Center Hospital in Japan from 2011 to 2020. We performed a survival analysis for each of these groups: (i) patients with ARM (n = 47); (ii) operable non-stage IV cases at initial presentation (n = 35); and (iii) stage IV cases (n = 32).

RESULTS

The 5-year overall survival (OS) was 53.6%, and the median OS was 78.7 months in patients with ARM. No statistically significant difference in 5-year OS was found between rectal and anal sites (50.9% vs. 56.7%). In the non-stage IV subgroup, the type of surgery (abdominoperineal resection or wide local excision) did not correlate with OS (HR 1.85; 95% CI 0.46-7.5; p = 0.39). In the stage IV subgroup, the 2-year OS of the ICI treatment group was 61.4%, whereas that of the dacarbazine regimen group was 0% (p = 0.048).

CONCLUSION

Our ARM prognosis was better than that of previous studies. Our findings suggest that the availability of ICI therapy may improve survival in patients with advanced ARM. However, further research is warranted to identify both the clinical and molecular predictors of response to improve patient selection.

BRAF, NRAS, KIT, TERT, GNAQ/GNA11 Mutation Profile and Histomorphological Analysis of Anorectal Melanomas: A Clinicopathologic Study

OBJECTIVE

Primary anorectal melanomas (AMs) are uncommon neoplasms with aggressive behavior. Molecular profile and clinicopathologic features of AMs are still not well established. In this study, we aimed to investigate BRAF, NRAS, KIT, TERT, and GNAQ/GNA11 mutation status and clinicopathologic features of AMs.

MATERIAL AND METHOD

All diagnostic slides of 15 AMs were reviewed. Histopathological and follow-up information were documented. Mutations in exon 15 of the BRAF gene; exons 2 and 3 of the NRAS gene; exons 9, 11, 13, 17, and 18 of the KIT gene; and exons 4 and 5 of the GNAQ/GNA11 genes and mutations in the promoter region of the TERT gene (chr.5, 1,295,228C > T and 1,295,250C > T) were analyzed.

RESULTS

BRAF(V600E) and KIT(V555I and K642E) mutations were observed in one (7%) and two cases (14%), respectively. NRAS, TERT and GNAQ/GNA11 mutations were not detected. The mean age was 65. Patients presented with rectal mass, rectal bleeding, pain, and weight loss. 73% of the lesions were macroscopically polypoid. The most common tumor cell type was epithelioid. Mean tumor thickness was 10.4 mm. One third of the cases lacked pigmentation. In situ melanoma was present in one third of the cases. Among 14 patients with follow-up data, 12 succumbed to disease. The mean overall survival was 36 months.

CONCLUSION

AMs are uncommon tumors with dismal survival, usually occurring in the elderly in various gross and microscopic appearances. In terms of molecular profile, BRAF and KIT mutations are rarely detected. Profiling of larger cohorts is required to elucidate the pathogenesis and to identify potential molecular indicators that may contribute to the development of individualized targeted therapies.

Clinicopathological profile and outcomes of anorectal melanoma from a tertiary care center in India

Background:

Anorectal melanoma (AM) is a rare subtype of melanoma.

Aim:

To study the clinic–pathologic features and outcomes in patients with AM.

Materials & methods:

Clinical, pathologic findings and outcomes of patients with AM were recorded.

Results:

Twenty-seven patients with AM were identified with median age of 57 years. Most patients presented in stage III (44.4%). Lymph node involvement was seen in 70.4%. The response to chemotherapy and immunotherapy was 16.6 and 25.0%, respectively. At a median follow up of 11 months, median overall survival was 30 months. Ballantine stage 3 and weight loss at presentation were predictors of poor survival.

Conclusion:

AM presents at an advanced stage with lymph node and distant metastasis.

Anorectal melanoma is a rare subset of melanoma presenting at an advanced stage with lymph node and distant metastasis. Early disease is managed surgically; however, optimal treatment of advanced disease is unclear. The stage at diagnosis is the most important prognostic factor. Prognosis is poor, but with the advent of targeted therapy and immunotherapy, the outcomes are improving.

Anorectal and Genital Mucosal Melanoma: Diagnostic Challenges, Current Knowledge and Therapeutic Opportunities of Rare Melanomas

Mucosal melanomas (MM) are rare tumors, being less than 2% of all diagnosed melanomas, comprising a variegated group of malignancies arising from melanocytes in virtually all mucosal epithelia, even if more frequently found in oral and sino-nasal cavities, ano-rectum and female genitalia (vulva and vagina). To date, there is no consensus about the optimal management strategy of MM. Furthermore, the clinical rationale of molecular tumor characterization regarding BRAF, KIT or NRAS, as well as the therapeutic value of immunotherapy, chemotherapy and targeted therapy, has not yet been deeply explored and clearly established in MM. In this overview, focused on anorectal and genital MM as models of rare melanomas deserving of a multidisciplinary approach, we highlight the need of referring these patients to centers with experts in melanoma, anorectal and uro-genital cancers treatments. Taking into account the rarity, the poor outcomes and the lack of effective treatment options for MM, tailored research needs to be promptly promoted.

Diagnostic performance of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in anorectal melanoma

To evaluate the diagnostic role of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) in initial staging and restaging of anorectal melanoma. This was a single-institution, retrospective observational study; patients for initial staging and with clinical or radiological suspicion of disease recurrence referred for PET/CT between January 2006 and December 2015 were included in the study. Diagnostic performance of PET/CT was evaluated for baseline staging and disease recurrence. A total of 61 patients who were referred for initial staging were included. PET/CT correctly detected primary lesion in 57 (93.44%) cases, regional nodes in 46 (75.4%) cases, nonregional nodes in 22 (36%) cases, and distant metastases in 25 (41%) cases. The sensitivity (SN); specificity (SP); positive predictive value (PPV); negative predictive value (NPV); and accuracy for primary lesion, regional nodes, nonregional nodes, and distant metastases were 96.6%, 100%, 100%, 50%, and 96.7%; 97.9%, 100%, 100%, 93.3%, and 98.4%; 100%, 100%, 100%, 100%, and 100%; and 100%, 100%, 100%, 100%, and 100%, respectively. A total of 24 patients were included for suspected recurrence/restaging. All the patients were treated previously by surgery, radiotherapy, or chemotherapy. PET/CT detected disease recurrence in 20 (83.3%) patients. Ten patients had recurrence at the primary site, 8 of whom also had distant metastases and 2 had only locoregional metastatic nodes. In the remaining 10 patients, there was no primary site recurrence; however, 2 patients had locoregional nodal and distant metastases and 8 patients had only distant metastases. PET/CT was false negative in 1 patient, which missed liver metastasis. SN, SP, PPV, and NPV of PET/CT was found to be 95%, 100%, 100%, and 75%, respectively, with accuracy of 96%. PET/CT demonstrates overall high diagnostic accuracy in the initial staging and detection of recurrent disease in cases of anorectal melanoma.

Anorectal Mucosal Melanoma: A Case Report and Literature Review

BACKGROUND Anorectal mucosal melanoma (AMM) is a rare and aggressive neoplasm, with a 5-year survival rate of 10%. Due to its rarity and nonspecific symptoms, the diagnosis is often made late. Surgical resection remains the criterion standard for treatment of anorectal melanoma. CASE REPORT We present the case of an 81-year-old woman presenting with hematochezia, anal secretion, tenesmus, difficulty in defecation, and perianal pain. On physical examination, there was a prolapse of a 5-cm melanocytic nodule in the anal canal, hard on palpation. Biopsy confirmed anorectal melanoma. Staging revealed anal and metastatic disease, with adrenal, lymphatic, and hepatic involvement. As the patient continued to have bleeding, severe pain, and difficulty in defecation, she was submitted to a wide local excision. At 5-month follow-up, the anal lesion had relapsed, and the patient died 10 months after the procedure. CONCLUSIONS AMM is a rare and extremely aggressive tumor. Symptoms are nonspecific but early diagnosis should be pursued to allow curative treatment. Surgical resection with free margins is the goal of surgical treatment. New therapies are being studied, including immunotherapy, which can improve the dismal prognosis of this rare disease.

Multimodality Imaging and Genetics of Primary Mucosal Melanomas and Response to Treatment

Mucosal melanomas (MMs) are rare and aggressive tumors that arise from melanocytes in the mucosal tissues that line the respiratory, gastrointestinal, and urogenital tracts. Most MMs occur during the 6th and 7th decades of life. MMs may be asymptomatic but may also cause bleeding, pain, and itching, depending on the site of origin. Because of their asymptomatic or oligosymptomatic nature and the difficulty of visualizing them in some cases, they are often advanced tumors at patient presentation. MM staging varies depending on the site of the primary tumor. A simplified staging system allows classification of clinically localized disease as stage I, regional nodal involvement as stage II, and distant metastasis as stage III. MM differs genetically from its cutaneous counterparts. Common drivers in cutaneous melanoma such as B-raf proto-oncogene serine/threonine kinase (BRAF) have a lower mutation rate in MM, whereas mutations of other genes including the KIT proto-oncogene, receptor tyrosine kinase (KIT) and splicing factor 3b subunit 1 gene (SF3B1) are more common in MM. Complete resection is the best curative option. However, surgical intervention with wide local excision and negative margins may be difficult to attain because of the local anatomy and the extent of disease. In addition, despite aggressive surgical resection, most patients develop local recurrence and metastatic disease. Recent advances in the treatment of melanoma include immunotherapy and targeted therapy. Unfortunately, MMs have a relatively poor prognosis, with an overall 5-year survival rate of 25%. Online supplemental material is available for this article. ^©RSNA, 2021.

Primary melanoma of the anorectal region: clinical and histopathological review of 17 cases. A retrospective cohort study

AIM

The aim of our study was to scrutinize diagnostic and treatment factors that may contribute to the low survival rate from anorectal melanoma while adding 17 more cases to the global research database.

METHOD

We carried out a retrospective analysis of 17 cases of anorectal melanoma treated at a single institution from 2000 to 2020. Data on patient age, sex, complaints, treatment and survival as well as tumour size, resection margins, histological and immunohistochemical features were assessed.

RESULTS

The median age of patients was 72 ± 12.49 (45-92) years. Most of the patients were women (n = 11, 64.71%). Three (17.65%) patients underwent no radical treatment. Of eight patients treated initially with radical surgery (either total mesorectal excision or abdominoperineal resection), six (75%) were found to have positive lymph nodes. Mean survival was 20 ± 23.46 (1-84) months. The average diameter of the resected tumours was 5.43 ± 3.02 cm (1.3-10 cm). Most tumours had epithelioid or spindle cell morphology and were positive for one or more melanocytic markers (S100, HMB-45 or MITF). More than half of the tumours contained no or very little melanin pigment. None of the tumours had significant lymphocytic infiltration. Three tumours showed positivity for keratins (PANCK or CAM5.2) and one tumour showed positivity for C-KIT stain.

CONCLUSION

An aggressive surgical approach may have an effect on survival in most early stages while more advanced disease benefits from a more conservative approach. Attention to sentinel lymph nodes and further systemic research into therapy is required. For now, treatment and diagnostic modalities seem to be inconsistent, requiring further investigation to elucidate common points.

Locally advanced anorectal malignant melanoma in septuagenarian patient treated by laparoscopic abdominoperineal resection: A case report

Introduction

Anorectal malignant melanoma (ARMM) is a rare disease with a poor prognosis. In cases involving locally advanced disease, the treatment strategy is difficult, especially in octogenarian patients, because the prognosis is poor, despite the corresponding decrease or loss of the anal function.

Presentation of case

A 78-year-old woman was admitted to a local hospital with chief complaints of severe anal discomfort due to an egg-sized tumor that was protruding out of the anus and melena. A diagnosis of ARMM was confirmed based on the examination of biopsy specimens and imaging study showed swollen lymph nodes on the dorsal side of the middle rectum and left internal iliac lymph nodes.

Laparoscopic abdominoperineal resection with left lateral lymph node dissection was performed. The examination of the resected specimen revealed two polypoid tumors with a maximum diameter of 38 mm and 14 mm with a metastatic lymph node of 62 mm in the mesorectum. The postoperative course was uneventful. Relapse and local recurrence free survival without any complaints was obtained for more than 12 months.

Discussion

With respect to locoregional disease control, it has been reported that abdominoperineal resection can obtain better control of local disease in comparison to local resection. Laparoscopic surgery is advantageous in its facilitation of an early postoperative recovery for elderly patient.

Conclusion

Laparoscopic abdominoperineal resection may control locoregional disease and improve the patient's QOL with early postoperative recovery. —even in septuagenarian patients—may become a treatment strategy for advanced ARMM.

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Anorectal malignant melanoma is a rare disease with a poor prognosis.

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Surgical procedure for anorectal malignant melanoma is controversial.

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APR may achieve better local control for advanced anorectal malignant melanoma.

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Laparoscopic surgery is advantageous in its facilitation of an early recovery for elderly patient.

Safety and efficacy of electrochemotherapy in a series of patients with nonmetastasized primary or recurrent anorectal malignant melanoma

Anorectal malignant melanoma (AMM) is a rare malignant tumor. Surgery remains the gold standard but new adjuvant treatments to allow local sphincter-saving are warranted. Electrochemotherapy (ECT) is an alternative to surgery in selected cohorts of patients. To evaluate safety and efficacy of ECT in a retrospective series of patients with primary or recurrent AMM in terms of local disease control, local progression free and overall survival. Seven primary and one recurrent AMM underwent ECT. Patients were followed at 1 and 2 months and at the longest available follow-up with clinical examination and/or ultrasound. One month after ECT 6/8 (75%) patients showed complete response, 1/8 partial response (12.5%) and 1/8 stable disease (12.5%), confirmed at 2 months. Bleeding stopped in all patients, and pain was absent or mild/moderate in all patients. No serious adverse events were observed. At 1 year of follow-up seven out of eight patients were alive (87.5%), four were disease-free and three were alive with disease. At the longest available follow-up (mean 4.9 ± 2.0 years) five out of eight (62.5%) of patients were still alive. Our study showed that ECT is well tolerated and effective in the treatment of patients with anal melanoma with good local control of disease.

18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Evaluation of Anorectal Malignant Melanoma: A Case Series

Melanomas are the malignancies that can affect any anatomic region where melanocytes exist (such as the epidermis, eyes, nasal cavity, and anus). Anorectal melanoma is a rare mucosal melanocytic malignancy, comprising 0.8% of all anorectal malignancies. Here, we report a case series of three patients of anorectal melanoma and role of positron emission tomography/computed tomography in diagnosis and follow-up to evaluate the local recurrence and distant metastases. Of three patients, two presented with rectal bleeding and one with obstruction. One patient had recurrence after 10 months, other after 24 months, and third remained disease free post surgery till 9 months.

Clinical and oncological outcomes of surgery in Anorectal melanoma in Asian population: A 15 year analysis at a tertiary cancer institute

INTRODUCTION

Anorectal malignant melanoma (ARMM) is an aggressive malignancy with dismal prognosis and a 5-year survival rate less than 20% in most of the previous studies. The ideal surgical treatment has still remained controversial. This retrospective study aims at analysing the outcome in patients with ARMM treated with curative surgical resection.

PATIENTS AND METHODS

This is a retrospective study of 38 patients of stage I anorectal malignant melanoma treated with curative surgical resection at our tertiary cancer institute.

RESULTS

WLE (Wide Local Excision) was carried out in 12 patients and APR (abdominoperineal resection) was done in 26 patients. The median overall survival of the entire group in this study was 20 months. Although the median overall survival of WLE patients was higher than those with APR (37 months versus 16 months, respectively), this was not a statistically significant event (P=0.317). The 1-, 2-, 3-, 5-year survival rates were similar with both APR and WLE with no significant difference in the 5-year survival rate (P=0.816); overall 5-year survival rate of just 13%. There were 3 long-term survivors in this study group who survived for more than 10 years.

CONCLUSION

Most patients ultimately succumb to the disease regardless of the management. Both APR and WLE have significant roles in the management depending on the subset of patients selected. Local treatment should be preferred wherever possible. Abdominoperineal resection should be offered in nodal disease or in a recurrent setting.

Anorectal Mucosal Melanoma in the Era of Immune Checkpoint Inhibition: Should We Change Our Surgical Management Paradigm?

BACKGROUND

The advent of immune checkpoint inhibition therapy has dramatically improved survival in patients with skin melanoma. Survival outcomes after resection of anorectal melanoma treated with immune checkpoint inhibition have not been reported.

OBJECTIVE

This study aimed to compare survival outcomes following surgical resection of anorectal melanoma between patients who received immune checkpoint inhibition and patients who did not.

DESIGN

This study is a retrospective analysis of data from a prospectively maintained database.

SETTING

This study was conducted at a comprehensive cancer center.

PATIENTS

Patients who underwent surgery for anorectal melanoma between 2006 and 2017 were included. They were stratified according to the use of immune checkpoint inhibition.

MAIN OUTCOME MEASURES

The primary outcomes measured were overall and disease-specific survival.

RESULTS

Of the 47 patients included in the analysis, 29 (62%) received immune checkpoint inhibition therapy. Twenty-two (76%) of the 29 patients received immune checkpoint inhibition after detection of metastasis or disease progression rather than in the neoadjuvant or adjuvant setting. Overall survival did not differ significantly between patients who received immune checkpoint inhibition therapy and patients who did not (median, 52 and 20 months; 5-year rate, 41% vs 35%; p = 0.25). Disease-specific survival also did not differ significantly. Our analysis did not identify any clinical or pathological features associated with response to immune checkpoint inhibition therapy or with survival.

LIMITATIONS

This study was limited by its relatively small sample and retrospective design and by the heterogeneous treatment regimen in the immune checkpoint inhibition group.

CONCLUSIONS

Immune checkpoint inhibition therapy by itself does not appear to improve survival in patients who undergo resection or excision of anorectal melanoma. Combinations of immune checkpoint inhibition with other therapeutic modalities warrant further investigation. See Video Abstract at http://links.lww.com/DCR/B499. MELANOMA DE LA MUCOSA ANORRECTAL EN LA ERA DE LOS INHIBIDORES DEL PUNTO DE CONTROL INMUNOLÓGICO: ¿DEBEMOS DE CAMBIAR NUESTRO PARADIGMA DEL MANEJO QUIRÚRGICO: El advenimiento de la terapia de los inhibidores del punto de control inmunológico, han mejorado dramáticamente la supervivencia en pacientes con melanoma de piel. No se han informado los resultados de supervivencia después de la resección del melanoma anorrectal, tratado con inhibidores del punto de control inmunológico.Comparar los resultados de supervivencia después de la resección quirúrgica de melanoma anorrectal entre pacientes que recibieron y no recibieron inhibidores del punto de control inmunológico.Análisis retrospectivo de una base de datos mantenida prospectivamente.Centro oncológico integral.Pacientes que se sometieron a cirugía por melanoma anorrectal entre 2006 y 2017. Los pacientes fueron estratificados según el uso de inhibidores del punto de control inmunológico.Supervivencia global y específica de la enfermedad.De los 47 pacientes incluidos en el análisis, 29 (62%) recibieron terapia de inhibidores del punto de control inmunológico. Veintidós (76%) de los 29 pacientes recibieron inhibidores del punto de control inmunológico después de la detección de metástasis o progresión de la enfermedad, en vez de administración adyuvante o neoadyuvante. La supervivencia global no varió significativamente entre los pacientes que recibieron o no recibieron terapia de inhibidores del punto de control inmunológico (mediana, 52 y 20 meses, respectivamente; tasa a 5 años, 41% frente a 35%, respectivamente; p = 0,25). La supervivencia específica de la enfermedad tampoco varió significativamente. Nuestro análisis no identificó ninguna característica clínica o patológica, asociada con la respuesta a la terapia de inhibidores del punto de control inmunológico o con la supervivencia.Muestra relativamente pequeña y diseño retrospectivo. Régimen de tratamiento heterogéneo en el grupo de inhibidores del punto de control inmunológico.La terapia por sí sola, de inhibidores del punto de control inmunológico, no parece mejorar la supervivencia en pacientes que se someten a resección o escisión de melanoma anorrectal. Las combinaciones de inhibidores del punto de control inmunológico con otras modalidades terapéuticas, merecen una mayor investigación. Consulte Video Resumen en http://links.lww.com/DCR/B499. (Traducción-Dr. Fidel Ruiz Healy).

Outcomes of Surgical Treatment for Patients with Anorectal Malignant Melanoma; Results of Nine Cases in a Single Institution

Anorectal melanoma (AM) is a rare and aggressive malignancy. Two main types of surgical approach for AM are abdominoperineal resection (APR) and wide local excision (WLE). Nine patients with AM underwent surgical treatment between July 2005 and October 2017 at our institution. Two of the patients were diagnosed with localized stage, four with regional stage, and three with distant stage. Laparoscopic APR was performed in six patients with localized and regional stages, whereas palliative APR and/or WLE were performed in those with distant metastasis. Both patients with localized stage lived without relapse for 6.8 years after surgery. One of the patients with regional stage had no relapse during 3.6 years of follow-up. The other three patients had recurrence and died between 6 and 32 months after surgery. The median overall survival (OS) of the cohort was 14.8 months, and the 5- and 10-year OS were 33.3% and 16.7%, respectively. The tumor at the regional stage could be removed through WLE, but preoperative diagnosis of lymph node metastasis is difficult in patients with AM. Further development of the diagnostic method is expected, and future tasks will be to establish the selection criteria to determine which surgical approach is optimal for this devastating disease.

Metastatic anorectal malignant melanoma causing ileocaecal junction obstruction due to contiguous spread

Malignant melanoma of the anal canal is a rare and aggressive tumour associated with significant mortality. Early diagnosis and early curative surgical resection have shown to offer a survival advantage. We present a case of 53-year-old woman, who was accidentally diagnosed to have a localised lesion of malignant melanoma of the anal canal on histopathology report of the specimen of haemorrhoidectomy done for thrombosed external haemorrhoids. She refused any form of treatment and did not return for follow-up. Two years after the initial diagnosis, she presented with intestinal obstruction. The malignant melanoma had become advanced with multiple metastases to the lungs, the liver, the peritoneum and the spine. The patient underwent a diverting loop ileostomy. At the time of surgery, it was found that the primary malignant melanoma of anal canal had contiguously involved the entire large intestine up to the ileocaecal junction and hence transverse colostomy could not be done.

Anal Melanoma: A Case Report of a Rare and Lethal Malignancy in a Suburban Nigerian Teaching Hospital

The aim of this report is to highlight the challenges involved in the diagnosis and treatment of anal melanoma in a tertiary hospital in Nigeria. It is a case report of an 84-year-old man who was managed for anal malignant melanoma. Despite inadequate investigative tools and less radical surgical treatment, the survival period of the index patient was comparable to the median survival quoted in the literature. Despite its rarity, mucosal melanomas also occur in the tropics. Prompt diagnosis, adequate imaging, and standardized treatment may improve its outlook in the nearest future.

Do Not Skip the Retroflexion: A Case of Disseminated Anorectal Mucosal Melanoma

Less than 4% of melanomas are of mucosal origin, with primary anorectal mucosal melanomas comprising a small subset. Mucosal melanomas are often diagnosed at an advanced stage due to delay in patient presentation and obscured tumor origins leading to a more aggressive behavior and less favorable prognosis when compared with cutaneous melanomas. We present a case of metastatic anorectal mucosal melanoma with a negative colonoscopy 1 year earlier.

Primary Malignant Melanoma of Anorectum CT Findings: a Single Tertiary Center's Experience

Anorectal melanoma is a rare malignancy with very aggressive course. This case series emphasize the role of imaging, contrast-enhanced computed tomography in evaluating such cases before surgery. CT scan of four patients with pathologically proven primary anorectal malignant melanoma was included. CT findings were analyzed from the picture archiving and communication system for the site of involvement, morphological shape, presence of perirectal and anal infiltration, lymphadenopathy, liver metastasis, and occurrence of bowel obstruction for all the four patients. All the four patients presented as polypoidal mass that caused focal expansion and obscuration of rectal lumen without causing colonic obstruction. Perirectal infiltration was seen in 2/4 patients and involvement of anal canal was seen in 3 patients. Distant metastasis was seen in the liver in three out of four patients. In conclusion, primary anorectal malignant melanoma is a rare, highly aggressive tumor and should be considered in patients with a bulky intraluminal polypoid mass that does not cause colonic obstruction in the anorectal region with large-sized lymphadenopathy.

Clinicopathologic Features of Cutaneous Malignant Melanoma and Their Impact on Prognosis

Introduction: Melanoma ranks 19th among malignancies overall and second among cutaneous types. The incidence worldwide has been on the rise over the last seven decades. Various prognostic factors have been assessed and found to have a profound impact on patient outcome. However, no such studies have been attempted in our population. Our study aimed to have an insight into the behavior of malignant melanoma in our population.

Materials and Methods: Cases of cutaneous malignant melanoma treated and followed up at our institute were included in this study. Cases of mucosal and choroidal melanoma were excluded. The parameters noted were age, gender, tumor thickness, Clark level, and presence of ulceration. These parameters were individually correlated with development of distant metastasis, two-year survival, survival duration, and primary tumor and lymph node stage. Appropriate statistical analyses were done.

Results: Thirty patients of cutaneous malignant melanomas were treated and followed up at our institution. There was male predilection of 1:1.5. Mean age at diagnosis was 50.1 years. Two-year survival was significantly better in females. Sun-exposed areas of the skin were most commonly involved followed by anal canal that has an unusually high incidence in our society. Majority of our cases were pT4(25) on tumor, nodal status, metastasis (TNM) staging at time of diagnosis. Increasing tumor thickness in terms of primary tumor staging was not found to have any significant impact on two-year survival, distant metastasis, lymph node stage, or survival duration. Sixty percent of cases had ulceration. There was no statistically significant effect on two-year survival (78% in ulcerated group vs 75% in nonulcerated group) and distant metastasis (61% vs 58.3%). In terms of Clark level, 20 cases were level V, seven cases were level IV, two were level III, and one was level I. There was no statistically significant difference between the Clark levels in terms of two years survival, development of distant metastasis, and lymph node stages.

Conclusion: Melanoma is an aggressive malignancy that causes high morbidity and morality. It commonly presents at an advanced stage at time of diagnosis in our population. Broader studies are required with early-stage melanomas to compare the various prognostic factors and their impact on prognosis.

A Rare Case of Primary Anorectal Melanoma and a Review of the Current Landscape of Therapy

INTRODUCTION

Anorectal mucosal melanoma (ARMM) is an uncommon and highly aggressive malignancy. Given its rarity, there is insufficient evidence on the optimal medical management which presents as a clinical challenge to its diagnosis and treatment. Treatment of ARMM typically involves a multimodal approach including surgical resection, chemotherapy, targeted therapy and/or immunotherapy.

CASE PRESENTATION

Here, we present a case of a 78-year-old female who presented with a four-month history of rectal bleeding and bowel incontinence. Ultimately, colonoscopy revealed a mass at the anal verge, and biopsy of the mass showed malignant cells that stained positive for S100, Melan-A and HMB-45, consistent with the diagnosis of malignant melanoma. Molecular testing revealed no BRAF, KIT or NRAS gene mutations. PD-L1 immunohistochemistry showed tumor proportion score of 1%. She underwent abdominoperineal resection with a plan to initiate immunotherapy with an anti-PD-1 checkpoint inhibitor. This case highlights a rare aggressive malignancy and reviews its treatment option, which are mostly extrapolated from its cutaneous counterpart and some derived from a few case reports. Due to its rarity, there is no consensus guideline for the treatment of ARMM.

Primary anorectal malignant melanoma with laparoscopic abdominoperineal resection: a case study and review of the relevant literature

ARMM is a disease with a poor prognosis. ARMM is often diagnosed at an advanced stage, and the 5-year survival rate of ARMM is < 20%. Although the number of case reports on ARMM is gradually increasing, the optimal treatment strategy for ARMM remains controversial. We report the case of an 81-year-old woman who had experienced bloody stool for 6 months before her diagnosis and who had been initially diagnosed with hemorrhoids. The pathological diagnosis of a biopsy specimen was malignant melanoma. Other examinations showed no evidence of lymph node or distant metastasis. Based on these results, laparoscopic abdominoperineal resection was performed. Three months later on her first follow-up examination, distant metastasis to the lung and liver was detected. Immunotherapy using Nivolumab was initiated to treat the recurrent disease. We reviewed the characteristics of a total of 1834 ARMM patients described in previous reports on ARMM for which the full text was available on PubMed. We experienced a case of ARMM. The prognosis of ARMM is still poor, regardless of the surgical procedure. Previous studies and our case report suggest that systemic therapy, such as immunotherapy using an anti-PD-1 ligand may be more important than reinforcement of local control for improving the prognosis of ARMM patients.

Primary Rectal Amelanotic Malignant Melanoma: A Rare Case Report

Malignant melanoma of the rectum comprises 0.5%-4% of all anorectal cancers. Malignant melanoma of the rectum is exceptionally a rare disease. It commonly affects the fifth or sixth decade, with nonspecific symptoms such as rectal bleeding or anal pain. After skin and retina, anorectum is the third common site for malignant melanoma. Proper diagnosis is difficult in the majority of cases due to lack of pigmentation and amelanotic histological appearance. Prognosis is very poor with a median survival of 24 months and five-year survival of 10%-15%. Anorectal malignant melanomas disseminate along the submucosal planes, therefore complete resection at the time of diagnosis is usually not possible.

A rare case of recurrent primary anorectal melanoma emphasizing the importance of postoperative follow-ups

BACKGROUND

Primary anorectal melanoma can be a rare differential diagnosis of anorectal mass. Due to the low case number reported in the literature, physicians are not aware of this aggressive disease. Although no consensus exists, wide local excision and abdominoperineal resection are considered the mainstay therapy.

CASE PRESENTATION

An 85-year-old female patient presented with fecal incontinence 5 years after local resection of a primary anorectal melanoma. In the rectoscopy, a tumor proximal to the dentate line was identified and later confirmed as a recurrent primary anorectal melanoma. There were no signs of locoregional or distant metastasis on the MRI and PET/CT. She underwent another wide local excision and regained fecal continence postoperatively.

CONCLUSIONS

Primary anorectal melanoma should belong to the differential diagnosis of anorectal mass. If technically feasible, wide local excision represents a less invasive treatment than abdominoperineal resection, retaining the anal sphincter and patient's quality of life. Even though wide local excision has a higher recurrence rate than abdominoperineal resection, there is no difference in survival between the two procedures. This is only under the premise that patients are followed-up regularly after wide local excision so that recurrence can be spotted early on and locally excised.

Peritoneal Carcinomatosis Arising from Primary Anorectal Melanoma

Anorectal melanoma is a rare and aggressive malignancy with a poor prognosis. Anorectal melanoma makes up approximately 1 to 3% of all anorectal malignancies. There are no known risk factors for anorectal melanoma. Patients frequently experience a delay in diagnosis due to multiple factors including nonspecific symptoms and misdiagnosis for other benign entities. Anorectal melanoma has a high potential for distant metastases and radiographic imaging plays a key role in evaluating for metastatic disease. Common sites for metastasis include pelvic lymph nodes, lungs, liver, skin, and brain. We present a case report of a 75 year old female with a history of transanal excision of primary anorectal melanoma who presented with increasing abdominal pain and distention. Computed tomography scan of the abdomen and pelvis showed metastatic disease to the peritoneum with findings of extensive peritoneal carcinomatosis, demonstrating the aggressive nature of anorectal melanoma.

Primary Dedifferentiated Amelanotic Anorectal Melanoma: Report of a Rare Case

Anorectal melanoma (ARM) is an uncommon aggressive malignancy that comprises 0.5% to 1.6% of all melanoma manifestations. Dedifferentiated melanoma is very rare with loss of all melanocytic differentiation markers and is usually seen in metastatic melanoma of cutaneous origin. In this article, we report the first case of primary dedifferentiated amelanotic ARM in a 68-year-old male who presented with anal discomfort that was initially treated as inflamed hemorrhoids. Physical examination revealed a large protruding anal mass, biopsy of which showed biphasic malignant tumor cells with distinct immunoprofiles: a superficial spindled/sarcomatoid component positive for SOX10 and S100, and a deeper epithelioid/rhabdoid component positive for desmin, AE1/AE3, and EMA. Both components were negative for HMB-45, Melan-A/MART-1, c-Kit, and other lineage markers. Molecular analysis by polymerase chain reaction demonstrated wild-type BRAF and KRAS genes. A diagnosis of dedifferentiated ARM was made based on the coexistence of a differentiated component (spindled: S100 and SOX10 positive) and a dedifferentiated component (epithelioid: all melanoma markers including S100 and SOX10 negative). Shortly afterwards, the patient developed extensive pulmonary and liver metastases and expired 20 days after the diagnosis was rendered, reinforcing the highly aggressive nature of this disease entity.

Anorectal Malignant Melanoma-Defining the Optimal Surgical Treatment and Prognostic Factors

Patients with anorectal malignant melanoma (ARMM) have a poor prognosis. Optimal surgical treatment is not defined. The aim of the study was to define the surgical treatment for ARMM, to compare the overall survival (OS) of abdomino-perineal resection (APR) and wide local excision (WLE) and to study various prognostic factors. Thirty patients of ARMM were managed, 20 with locoregional disease, 10 metastatic. Of the 20 patients with locoregional disease, 15 underwent APR and 5 WLE. The 1-, 2-, 3-, and 4-year overall survival rates (by Kaplan-Meier survival analysis) in the APR group were 67, 40, 40, and 32%, and in WLE group were 100, 100, 67, and 67% respectively. Median survival for APR and WLE groups were 13 and 36 months and were not significant (p 0.48). Node-negative patients had better survival than node positive in the APR group (56 vs. 13 months) (p 0.017). Patients with tumor size < 2cm, lymphovascular invasion and perineural invasion negative, and margin-negative and with superficial infiltration had a trend toward better survival than their counterparts. WLE gives an equivalent oncological outcome and can be offered for patients with smaller ARMM and APR for locally advanced, larger tumors or as a salvage following recurrence after WLE.

Morphologic and Immunohistochemical Characteristics of Anorectal Melanoma

Anorectal melanoma is a rare aggressive disease. Due to its rarity and considerable histologic and immunohistochemical variabilities, misdiagnosis as lymphoma, carcinoma, sarcoma, and/or gastrointestinal stromal tumor is not uncommon, particularly in amelanotic cases. We reviewed histologic features and immunohistochemical stains of 19 anorectal melanoma cases. Histopathologic features were evaluated including junctional activity, melanin pigment, and morphologic features. Immunohistochemical stains were performed using Sox10, S100 protein, HMB-45, melan-A, CD56, and cytokeratins. Epithelioid histopathologic morphology was observed in 63.2% of the cases followed by 47.4% of the cases with spindle-cell, 26.3% with lymphoma-like, and 26.3% with pleomorphic morphologies. Junctional melanocytic activity was seen in almost half of the cases. Melanin pigment was absent (amelanotic) in nearly 40% of the cases. Immunohistochemically, diffuse positive expression of Sox10, S100 protein, melan-A, and HMB-45 was seen in 100%, 40%, 53.3%, and 38.5% of the cases, respectively. Cytokeratins were negative and CD56 was positive in 2 cases. These findings indicate that anorectal melanomas often show one or combined histolopathologic features without presence of melanin pigment and absence of junctional melanocytic activity. Anorectal melanoma should be kept in mind in the differential diagnosis of malignant neoplasms of anorectal region with epithelioid, spindle-cell, lymphoma-like, and pleomorphic morphologies. Sox10 immunohistochemistry stain can be used as a first-line screening tool to avoid extensive or unnecessary workups and/or potential misdiagnosis.

Hyperprogressive Disease in Anorectal Melanoma Treated by PD-1 Inhibitors

The 5-year survival rate of primary anorectal malignant melanoma is less than 20%. Optimal treatment of this condition remains controversial regarding locally disease, and whether any preferential survival benefit arises from either abdominoperineal resection or wide local excision remains unknown. The majority of patients progress to metastatic disease, and for decades, the use of chemotherapies, such as platines or dacarbazine, has been advocated to improve overall survival. The therapeutic use of new checkpoint inhibitors in a variety of trials has provided evidence for an antitumoral effect of PD-1 and/or CTL4 inhibitors in mucosal melanomas, but these treatments must still be further evaluated. Some anecdotal occurrences of rapid progression [i.e., hyperprogressive disease (HPD)] while using these immune agents have been described, suggesting potentially deleterious effects of these drugs for some patients. We report a 77-year-old male metastatic anorectal melanoma patient presenting with HPD over 2 months of a PD1 inhibitor treatment course and document this HPD blood phenotype.

Malignant rectal melanoma in 2 dogs

Two rare cases of malignant rectal melanoma in dogs are described. Tumors were locally invasive and composed of spindle cells arranged in interweaving bundles, sheets, and nests within preexisting fibrovascular stroma. Mitotic count was high. The diagnosis was achieved based on histopathology and immunohistochemistry for PNL2 and melan-A.

Anorectal mucosal melanoma

Anorectal melanoma is an uncommon and aggressive mucosal melanocytic malignancy. Due to its rarity, the pre-operative diagnosis remains difficult. The first symptoms are non-specific such as anal bleeding, anal mass or pain. Although anorectal melanoma carries a poor prognosis; optimal therapeutics strategies are unclear. Surgical resection remains the mainstay of treatment. The optimal surgical procedure for primary tumours is controversial and can vary from wide local excision or endoscopic mucosal resection (EMR) to an abdomino-perineal resection. A high degree of uncertainly exists regarding the benefit of radiation therapy or chemotherapy. The treatment of advanced melanoma is evolving rapidly with better understanding of the disease biology and immunology. Considerable effort has been devoted to the identification of molecular determinants of response to target therapies and immunotherapy.

Anorectal Melanoma: An Unusual Cause of Rectal Bleeding

Anorectum is a rare site for primary melanoma. It is an aggressive cancer with poor prognosis. The diagnosis is often delayed due to non-specific signs and symptoms. Clinically, it is often misdiagnosed as hemorrhoids. The cytological diagnosis can be challenging especially when melanin pigment is sparse or absent. Herein, we present a rare case of anorectal melanoma which was initially misdiagnosed as hemorrhoids. A final correct diagnosis was made on cytology when later on the patient developed inguinal metastasis.

Cancer of the Anal Canal: Diagnosis, Staging and Follow-Up with MRI

Although a rare disease, anal cancer is increasingly being diagnosed in patients with risk factors, mainly anal infection with the human papilloma virus. Magnetic resonance imaging (MRI) with external phased-array coils is recommended as the imaging modality of choice to grade anal cancers and to evaluate the response assessment after chemoradiotherapy, with a high contrast and good anatomic resolution of the anal canal. MRI provides a performant evaluation of size, extent and signal characteristics of the anal tumor before and after treatment, as well as lymph node involvement and extension to the adjacent organs. MRI is also particularly helpful in the assessment of complications after treatment, and in the diagnosis for relapse of the diseases.

Abdominal perineal resection or wilde local excision in primary anorectal malignant melanoma. Case report and review

Introduction

Primary anorectal malignant melanoma is a rare and aggressive tumor that carries a poor prognosis. Anorectal melanoma (ARM) is often misdiagnosed as hemorrhoids adenocarcinoma polips and rectal cancer. ARM spreads along sub-mucosal planes and is often to wide-spread for complete resection at time of diagnosis and almost all patients die because of metastases.

Presentation of the case

A 77-year-old male patient presented a history of recurrent rectal bleeding and whose histopathological diagnosis was melanoma.

Discussion

The treatment of choice remains controversial. Surgery with complete resection represents the typical treatment. However standard operative procedures related to the area of resection and lymph dissection have yet to be established. Abdominal perineal resection (APR) with or without bilateral inguinal lymphadenectomy or wide local excision (WLE) have been used to manage patients with ARM.

Conclusion

The higher serum levels of LDH and YKL-40 are suggestive for Anorectal Melanoma diagnosis. The decrease of these findings may be associated with good prognosis. The review of both APR and WLE options suggests no significant difference in survival among patients.

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Anorectal melanoma (ARM) is a systemic disease.

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Regardless how aggressive is ARM, no surgical treatment will truly change the outcome.

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If surgical teqchniques are available, patients should undergo to wide local excision.

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In case of recurrence, the abdominal resection should be considered as the best surgical treatment.

Primary anorectal melanoma-a rare entity: case report

Anorectal melanoma is a rare disorder. There have only been a few cases reported and there is no consensus of treatment. We report a case of 50-year-old Caucasian man presenting intermittent prolapse of an anorectal mass during 6 months with occasional bleeding. Biopsies came up with the diagnosis of malignant melanoma. No distant metastases were found. He underwent an abdominoperineal resection due to internal sphincter invasion. A second tumour was diagnosed in final histologic examination: a dysplastic rectal polyp invaded by the melanoma (collision tumour). At 12 months of follow up he presented loco-regional recurrence (a single pelvic lymph node) and hepatic metastases. He was included in a study protocol comparing new medical treatments (nivolumab versus ipilimumab or both).

Clinical and Imaging Features of Noncutaneous Melanoma

OBJECTIVE

The purpose of this article is to summarize the epidemiologic characteristics, clinical aspects, and radiologic appearance of as well as the management considerations and differential diagnoses for noncutaneous primary melanomas occurring at specific anatomic sites. Primary ocular, sinonasal, meningeal, biliary, adrenal, alimentary tract, and genitourinary melanomas are highlighted.

CONCLUSION

Noncutaneous primary melanomas are a complex group of malignancies with biologic findings that are unique when compared with findings for cutaneous melanomas. Each noncutaneous primary melanoma has its own specific diagnostic and management challenges, depending on the anatomic location where they arise.