Anal neoplasms

Premalignant and Malignant Perianal Lesions

Anal cancer is a heterogeneous and rare disease process that accounts for ∼1.5% of all gastrointestinal tract malignancies. The perianal skin plays host to a variety of different premalignant and malignant lesions, all with variable histology, treatment options, and prognosis. Anal cancers in general are notorious for having a delayed or missed diagnosis leading to treatment delays and may have an impact on survival. This delay is in part due to the nonspecific symptomatology and also improper physical examination of the sensitive and anatomically complex perianal region and anal canal. This article examines the various types of perianal cancers and their precursor lesions and will explore treatment options as well as outcomes and prognosis.

Anal Malignant Melanoma Manifesting Hepatic Metastases Shown on FDG PET/CT

Multiple hepatic metastases are uncommon as initial presentation of primary anal malignant melanoma. We report FDG PET/CT findings of pathology-proven hepatic metastases from anal malignant melanoma of unknown origin in a 43-year-old woman whose initial presentation was worsening abdominal pain.

Perianal Paget's disease: case report and review of the literature

A peri-anal skin lesion, often eczema-like and with symptoms of pruritus, that does not resolve after classical local therapy should be biopsied. We present a case of peri-anal extramammary Paget's disease (EMDP) and associated anal adenocarcinoma. Reviewing the literature, more than 30% of patients with EMDP present a second primary tumour in their past, present or future history. In Europe, the risk of developing a new primary tumour in patients with this condition is increased compared with the standard population. In cases of peri-anal Paget's disease (PPD), specific histochemical markers allow us to differentiate between a primary and a secondary form, the secondary one is strongly associated with colorectal and anal tumours. We provide information about the most commonly suggested therapy for PPD with or without associated malignancy and about the recommended follow-up.

Tumours and inflammatory lesions of the anal canal and perianal skin revisited: an update and practical approach

Tumours of the anal and perianal region are relatively rare, and clinically often interpreted as innocuous lesions, leading to frequent delays in diagnosis and adequate treatment. Although squamous cell neoplasia represents the most common entity encountered in this anatomically complex area, many conditions, both neoplastic and inflammatory, may occur. Adding to the challenge of correct diagnosis and patient management, recent years have seen major updates in the terminology of squamous cell neoplasia, created to reflect advances in our understanding of the role of human papilloma virus and unify previous terminologies used for different sites in the anogenital tract. However, squamous cell neoplasia in the anal canal and perianal region may differ in terms of histology, biological behaviour, staging and treatment. The aim of this review is to present an overview of neoplastic and non-neoplastic lesions that may be seen in this area, an update on important developments and terminology, potential pitfalls that may be encountered in routine pathology practice and a practical approach on how to resolve these issues.

Anal cancer: current standards in care and recent changes in practice

Answer questions and earn CME/CNE The management of squamous cell carcinomas of the anal canal has evolved from surgery as first-line treatment to curative chemoradiation, with surgery reserved for salvage. Significant progress has been made in understanding how to most effectively deliver chemotherapy and reduce toxicity through advancements in radiation delivery. The purpose of this article is to review the multimodality approach to the diagnosis and management of anal cancer based on a review of the published data and in light of available guidelines.

Anal canal squamous cell carcinoma: overview, surveillance after treatment and management of local recurrence

SUMMARY Anal canal cancer is an uncommon gastrointestinal malignancy, although the incidence is increasing. Current treatment employs definitive chemoradiation, 5-fluorouracil, mitomycin C and a radiation dosage of 54–59 Gy for T3/T4 tumors, but not for T1 and T2 disease. Surveillance after completion of treatment is required. One acceptable strategy includes physical examinations every 3–6 months for 5 years and serial CT scans to detect advanced disease. A total of 40% of patients with T4 disease or immunosuppressed status may recur within the first 2 years after completion of treatment. Salvage therapy includes radical abdominoperineal resection. The most significant prognosticator after salvage surgery is the resection margin. Generally, patients with anal cancer should be treated by a multidisciplinary physician team and be assigned to clinical research trials, if feasible.

Anorectal melanoma

Anorectal melanoma is a disease that can be difficult to diagnose because of its unclear presentation. After diagnosis, the main treatment available is surgical resection. Sentinel lymph node mapping has an unclear role in its management. Adjuvant therapy has long been recommended; however, there are no strong data to support its use. Prognostic factors to help gauge survival are also not clear; nevertheless, there is a strong association between stage of disease and histologic perineal invasion. Anorectal melanoma is a very rare disease with a dismal prognosis.

Premalignant neoplasms and squamous cell carcinoma of the anal margin

Premalignant and malignant lesions of the anal margin are rare. Understanding anal anatomy and performing a biopsy of any suspicious lesions are essential in avoiding a delay in diagnosis and appropriately treating these tumors. Wide local excision continues to remain the treatment of choice for many of these lesions. Combined multimodality treatment has come to play an important role in managing patient with more advanced or metastatic disease.

Anal neoplasms

A variety of lesions comprise tumors of the anal canal, with carcinoma in situ and epidermoid cancers being the most common. Less common anal neoplasms include adenocarcinoma, melanoma, gastrointestinal stromal cell tumors, neuroendocrine tumors, and Buschke-Lowenstein tumors. Treatment strategies are based on anatomic location and histopathology. In this article different tumors and management of each, including a brief review of local excision for rectal cancer, are discussed in turn.

Primary Small Cell Malignant Melanoma of the Rectum: Case Report of a Very Rare Tumor

Rectal/anorectal malignant melanomas are highly aggressive tumors with a poor prognosis and low 5-year survival rate. They are also very rare. Of the well-known histological variants of malignant melanoma, the small cell subtype is also very uncommon; consequently, small cell anorectal malignant melanoma is an exceedingly rare occurrence. In this article, the authors provide a detailed clinicopathological description of small cell malignant melanoma of the rectum, documenting clinical, histological, immunohistochemical, and ultrastructural features, to add to the sparse references on this tumor in the literature. The patient was a 53-year-old woman with a mass 2 cm from the anus, which was surgically removed. In histological sections, the tumor was a small cell malignant melanoma, with a tumor cell diameter of 7.6+/-1.0 microm, and a range of 5.5-10.7 microm (N = 100). Tumor cells were positive for S-100 protein and HMB-45 and contained sparse but unambiguous type II melanosomes. This article is one of the few detailed clinicopathological documentations of a small cell malignant melanoma of the rectum (anorectum) and the first to have the diagnosis confirmed ultrastructurally by the identification of melanosomes. The present case adds to the 3 mainly or entirely small cell anorectal malignant melanomas described in the literature. There are also at least 12 other cases with less well-defined numbers of small tumor cells or with small cells admixed with other cell morphologies. Documentation of these unusual morphological variants is important for identifying any distinctive outcome they might exhibit compared with conventional malignant melanoma.

Malignancies of the anal margin and perianal skin

Malignancies of the anal margin and perianal skin are relatively uncommon lesions, comprising 3 to 4% of all anorectal malignancies. Commonly included in this group of cancers are Bowen's disease (intraepithelial squamous cell cancer), perianal Paget's disease (intraepithelial adenocarcinoma), invasive squamous cell cancer, basal cell cancer, and malignant melanoma. Buschke-Lowenstein tumor, or giant condyloma acuminatum, is not always included because this lesion is technically benign, although it displays aggressive local invasive behavior that makes it difficult to manage. Complaints are usually nonspecific, such as itching or burning, bleeding, pain, drainage, or a mass. Proper diagnosis requires a high index of suspicion on the part of the surgeon. Innocent local irritations will resolve in a short time with appropriate therapy; those that persist must be biopsied for tissue diagnosis. Wide local excision is the mainstay of treatment for early stage tumors as it preserves continence and obtains adequate local control. Adjunct therapies have been utilized in more advanced or recurrent lesions, including radiotherapy, photodynamic therapy, and imiquimod. All have met with a fair amount of success in controlling local disease; however, the number of patients treated in each instance is small, making it difficult to design an evidence-based treatment strategy. Invasion and metastasis are relatively rare in this group of neoplasms; perianal Paget's disease has the highest risk of associated underlying neoplasm. The most important consideration in developing a treatment strategy is which strategy would achieve the best clinical result with the least morbidity to the patient.

Outcomes of salvage surgery for squamous cell carcinoma of the anal canal

BACKGROUND

For patients with anal canal cancer who fail combined modality treatment (CMT), salvage surgery (SS) offers the potential for long term survival. The literature regarding SS is limited by small patient numbers and/or heterogeneous treatment protocols. We report on a large series of patients initially treated with chemoradiation at a major referral center.

METHODS

We identified 60 patients with persistent or recurrent anal cancer who had undergone SS; 20 were excluded. Overall and disease-free survival (OS, DFS) curves were constructed using the Kaplan Meier method. Univariate analysis was done using the Log-Rank test, and multivariable analysis using Cox proportional hazards.

RESULTS

The 40 patients (29 women, 11 men, median age 57) underwent curative intent resection. The initial procedure was multivisceral resection (n = 24), abdominoperineal resection alone (n = 14) or local excision (n = 2). Postoperative mortality was 5%. Postoperative complications were seen in 72%. Median follow-up was 18 months overall and 36 months in survivors. Median OS was 41 months; OS and disease free survival at 5 years were 39% and 30%, respectively. Recurrence was present in 21 patients at time of analysis. Failure was locoregional in 86% (18 of 21) and distant in 48% (10 of 21). Independent predictors of poor OS were male gender, Charlson Comorbidity Score and tumor size. Independent predictors of poor disease free survival were positive margins and lymphovascular invasion.

CONCLUSION

SS for anal canal cancer was associated with significant morbidity. Long-term survival was achieved in 39% of patients. Comorbidities should guide patient selection, and R0 resection should be the goal.

Justification for staging of epidermoid anal carcinoma after salvage surgery: a pathological guideline

The currently accepted first line treatment for epidermoid anal cancer is chemoradiotherapy (CRT). Tumour size and adjacent organ involvement are the key in the pretreatment assessment for T1-T4 tumours respectively. Residual or recurrent disease following initial CRT, is best treated by salvage anorectal excision. Pathological staging systems of resections were historically validated when surgery was the primary treatment and are therefore in need of revision. We propose a new pathological staging system for salvage anorectal excision specimens to allow improved prognostic guidelines postoperatively.

Management of Less Common Tumors of the Colon, Rectum, and Anus

The majority of colorectal and anal malignancies are adenocarcinomas and squamous cell cancers, respectively. Despite the predominance of these neoplasms in these locations, rare histiotypes of the colon, rectum, and anus do occur. These histotypes include but are not limited to lymphoma, melanoma, diffuse cavernous hemangioma, and sarcomas, such as leiomyosarcoma or Kaposi's sarcoma. These tumors often present challenges to clinicians with respect to diagnosis, staging, management, and pathology because of their unfamiliarity. A Medline search using "colon," "rectum,""anus," "lymphoma," "melanoma," "diffuse cavernous hemangioma," "squamous cell carcinoma," "carcinoid," "sarcoma," "leiomyosarcoma," "Kaposi's sarcoma," "Paget's disease," "Bowen's disease," and "basal cell carcinoma" as key words was performed as well as a cross-referencing of the bibliography cited in each work. Rare tumors of the colon, rectum, and anus present diagnostic and management dilemmas for clinicians. Because of their infrequency and poor prognosis, the optimal management of these tumors is controversial. For some histotypes, such as squamous cell carcinoma and carcinoids of the rectum, treatment depends on location and size of the tumor. For uncommon anal lesions, such as Bowen's disease, Paget's disease, and basal cell carcinoma, wide local excision (WLE) with negative margins is the standard of care. For other lesions such as anorectal melanoma or leiomyosarcoma, abdominal perineal resection versus WLE is still being debated. Because the optimal treatment of these tumors is still unclear, we recommend a multidisciplinary approach including a surgeon, primary care physician, medical oncologist, radiation oncologist, and pathologist to offer the patient the best outcome.

Salvage Abdominoperineal Resection and Perineal Wound Healing in Local Recurrent or Persistent Anal Cancer

The primary treatment for anal cancer is chemoradiation (CRT). Failures after CRT are potentially curable with an abdominoperineal resection (APR). A major problem of surgery in the anal area is poor healing of the perineal wound. Between 1985 and 2000, 129 patients treated for anal cancer were retrospectively reviewed. Of the 24 patients with local failure, 18 patients were treated with an APR. The aim of this study was to review the results and long-term outcome after salvage APR, with special emphasis on perineal wound healing. Mean age at diagnosis was 59 (range: 41-83) years. After a median of 16 months, only 2 patients developed a local recurrence. The 5-year overall survival was 30%. In 11 patients the perineal wound was closed primarily, in 3 patients the perineal wound was left open, and in 4 patients a vertical rectus abdominus musculocutaneous (VRAM) flap was used. Perineal wound breakdown occurred in 5 of the 14 patients (36%) not treated with primary muscle reconstruction. In all patients treated with a VRAM flap the perineal wound healed primarily. In the present study salvage APR in recurrent or persistent anal cancer results in good local control and 5-year overall survival of 30%. When performing an APR a VRAM flap reconstruction should be considered to prevent disabling perineal wound complications.

Citologia anal como método de rastreamento para a detecção precoce do câncer anal: esfregaços com algodão hidrófilo são mesmo insatisfatórios?

OBJETIVO: Testar se swabs de algodão hidrófilo são capazes de produzir esfregaços de secreção anal que permitam leituras citológicas satisfatórias ao Pap-a em comparação a métodos tradicionais de coleta. MÉTODOS: 318 pacientes sofreram coleta de material anal para a realização do Pap-a. 180 deles realizaram a captura de células anais com material sorteado (escova citológica, swab de poliéster ou cotonete de algodão). Foram comparados entre si os materiais usados para a coleta de secreção anal segundo a capacidade de produção de leitura citológica satisfatória. RESULTADOS: Não houve diferença estatística entre o algodão hidrófilo, o poliéster e a escova na capacidade de produzir leituras citológicas satisfatórias (p>0,05). CONCLUSÃO: No material estudado, o algodão hidrófilo foi tão bom quanto o poliéster ou a escova citológica na produção de leituras citológicas adequadas no Pap-a.

Overview of anal cancer for the surgeon

Cancers of the anal canal represent a diverse group of pathology and require a multidisciplinary approach for treatment. For the most common anal canal cancer, anal SCC, the primary therapy is CMT with systemic chemotherapy and radiation. The surgeon plays a key role in the diagnosis and follow-up after treatment, with surgical intervention reserved for residual or recurrent disease. The overall prognosis for this disease is favorable. For anal adenocarcinoma, aggressive surgical resection remains the mainstay of therapy, with radiation therapy and chemotherapy used to aid in local disease control and for treatment of metastatic disease. A high rate of distant failure in this disease is responsible for the poor long-term prognosis. Anorectal melanoma has a high rate of distant failure and a poor overall survival rate. Surgical intervention is focused on local disease control with preservation of sphincter function. The biggest improvements in survival for this disease will come with more effective systemic therapy.

Uncommon anal neoplasms

The neoplasms of the anus discussed in this article are uncommon, and therefore lack a consistent diagnostic and treatment algorithm derived from prospective clinical trial datasets. There may be an opportunity to design prospective Phase II clinical trials, with established uniform surgical pathology, surgical technique guidelines, and endpoints. The American College of Surgeons Oncology Group may have an opportunity to design and carry out controlled clinical trials for select rare anal neoplasms. Such an effort may yield modern benchmarks with which to base subsequent patient care algorithms.

Anorectal anatomy and embryology

The anal canal is complex in its anatomy and its embryologic origin. The intricate and changing histology of the anal canal explains the different types of anal cancer. In addition, an understanding of the venous and the lymphatic drainage of the anal canal helps to explain its methods of dissemination. Finally, the basis for the treatment of anal cancer is derived from the cancer's anatomic origins.