Primary and secondary adenocarcinomas associated with anal fistulae

Perianal Mucinous Adenocarcinoma: A Case Report and a Systematic Review of the Literature

BACKGROUND

Mucinous adenocarcinoma of anus is an uncommon neoplasm of the gastrointestinal tract. In most of the cases, early diagnosis of this disease is difficult since its symptoms frequently mimic benign inflammatory conditions.

METHODS

A systematic PubMed and Scopus search was conducted, a propos of a case report.

RESULTS

One hundred fifty patients from 93 case reports were included. The mean age of the patients was 60.5 years (range: 18-81). The majority of them were males (124 out of 150, 82.7%), while the main known risk factor was the history of chronic fistula (109 out of 150, 72.7%). Recurrent perianal sepsis and perianal pain were the principal symptoms at the time of presentation. No symptoms have been reported only in three patients (3 out of 150, 2%). Regarding the prior surgical history of the patients, multiple abscess drainage and perianal fistula's related interventions were present in 62 (41.3%) and 19 (12.7%) patients, respectively. Neoadjuvant chemoradiotherapy was administered in 53 out of 150 patients (35.3%), while the majority of them have been treated with combined treatment of chemotherapy and radiotherapy. APR and its variations were the most applied surgical treatment (68%). Adjuvant chemoradiotherapy was administered almost up to one-third of the included patients (34%). Recurrence of the disease was reported in 41 out of 150 patients (27.3%). Death was reported in 44 out of 150 patients (29.3%).

CONCLUSION

Review of the available published literature suggests that perianal mucinous adenocarcinoma is an extremely rare neoplasia. Τhere is no consensus as far as the diagnosis and the treatment strategies, due to the rarity of this neoplasm. High degree of clinical suspicion as well as histopathological confirmation is the principal requisites for the diagnosis of mucinous adenocarcinoma, especially in the ground of chronic ulcero-proliferative perianal lesions.

Adenocarcinoma arising from a chronic perianal fistula in a Crohn's disease patient: case report and review of the literature

Crohn's disease patients frequently develop perianal fistulas during their life. They are also at higher risk to develop cancers. Rarely, those cancers appear within a prior chronic fistula. The main types are adenocarcinoma mostly mucinous and squamous cell carcinoma. They are generally discovered at an advanced stage with a poor prognosis because symptoms are generally the same as those of the fistula itself. Regular follow-up of chronic fistulas is then important for an early diagnosis as well as histological analysis of the fistula during surgery. There is no consensus on the ideal treatment but abdominoperineal resection is the corner stone with or without neo or adjuvant chemo-radiotherapy. This paper presents a rare case of mucinous adenocarcinoma in a chronic perianal fistula in a Crohn's disease female and provides a review of the literature.

Fistula-Associated Anal Adenocarcinoma: A 20-Year Single-Center Experience

BACKGROUND

Fistula-associated anal adenocarcinoma (FAAC) is a rare consequence in patients with long-standing perianal fistulas. A paucity of data are available for this patient collective, making clinical characterization and management of this disease difficult.

OBJECTIVE

This study aimed to describe a single-center experience with FAAC patients, their clinical course, and histopathological and molecular pathological characterization.

METHODS

All patients receiving surgery for an anal fistula in 1999-2019 at a tertiary university referral hospital were included in this retrospective analysis. Patients with FAAC were eligible for histopathological analysis, including immunohistochemistry and molecular profiling.

RESULTS

This study included 1004 patients receiving surgical treatment for an anal fistula, of whom 242 had an underlying inflammatory bowel disease (IBD). Ten patients were diagnosed with a fistula-associated anal carcinoma (1.0%), and six of these patients had an FAAC (0.6%). The mean overall survival of FAAC patients was 24 ± 3 months. FAAC immunohistochemistry revealed positive staining for CK20, CDX2 and MUC2, while stainings for CK5/6 and CK7 were negative. All FAAC specimens revealed microsatellite stability. Molecular profiling detected mutations in 35 genes, with the most frequent mutations being TP53, NOTCH1, NOTCH3, ATM, PIK3R1 and SMAD4.

CONCLUSION

FAAC is rare but associated with poor clinical outcome. Tissue acquisition is crucial for early diagnosis and therapy and should be performed in long-standing, non-healing, IBD-associated fistulas in particular. The immunophenotype of FAAC seems more similar to the rectal-type mucosa than the anal glands.

Adjuvant chemoradiotherapy does not improve outcomes in patients with fistula-associated anal adenocarcinoma undergoing abdominoperineal resection

OBJECTIVE

Abdominoperineal resection (APR) is currently established as a standard treatment regimen for fistula-associated anal adenocarcinoma (FAAA), however, the efficacy of chemoradiotherapy (CRT) remains unclear. The aim of this study is to evaluate the role of CRT in patients with FAAA treated with APR through single-center experience and literature review.

METHODS

A retrospective review was performed on patients with FAAA consecutive treated in our institution from 2005 to 2022. In addition, a systematic literature search was performed using PubMed and MEDLINE. All patients with FAAA who received APR in our institution and reported in the literature were included and divided into three categories for statistical analysis: APR alone (APR group), neoadjuvant therapy combined APR (CRT+APR group), and APR combined postoperative therapy (APR+CRT group).

RESULTS

Fifteen patients with FAAA were identified from our retrospective charts review. At a median follow-up time of 18 months, the recurrence-free survival rate was 53.3% and the survival rate was 73.3%. Eight patients underwent APR and 6 received postoperative chemotherapy. Among them, one died, one developed recurrence and the remaining six patients were alive with disease free. We found 37 publications describing 62 patients with FAAA treated with APR. Clinical data from these articles were analyzed together with the 8 cases in our institution. The overall survival rates were 94.1%, 70.8%, and 38.5% at 1-, 3-, 5-years respectively. Combining (neo)adjuvant therapy did not appear to improve outcomes in FAAA treated with APR (CRT+APR vs. APR, p=0.977; APR+CRT vs. APR, p=0.351). Lymph node involvement was shown to be significantly associated with poor outcomes by multivariate analysis (p=0.020).

CONCLUSIONS

For patients with FAAA without lymph node involvement, APR is adequate to control disease and the addition of CRT does not appear to prolong survival.

Extensive Resection for Treatment of Locally Advanced Primary Mucinous Adenocarcinoma Arising From Fistula-in-Ano

We report a case of a 66-year-old male who presented with a locally advanced primary mucinous adenocarcinoma arising from a fistula-in-ano. The presentation was typical for perianal sepsis and fistula-in-ano with anal pain and chronic discharge. Initial treatments with fistula debridement and seton were performed. Subsequent review of histology revealed underlying adenocarcinoma, while magnetic resonance imaging (MRI) showed local invasion into the prostate. The patient received neoadjuvant chemoradiotherapy followed by pelvic exenteration to maximize the chance of achieving cure. Features of this case are discussed together with its implications, including treatment guidelines and typical MRI findings.

Recent advances in the management of anal cancer

Anal cancer is a rare condition, although its incidence has been increasing over the past several decades, particularly in women. The majority of anal cancers are squamous cell cancers and are linked with human papilloma virus (HPV) infection. Recent work in HPV basic science has delineated the mechanism by which the virus leads to the development of anal cancer. With widespread availability of an HPV vaccine since 2006, vaccination has become an important strategy for anal cancer prevention. However, in the US, there remain no guidelines for anal cancer screening. Treatment of anal cancer is dictated largely by accurate staging, which is generally accomplished with a combination of physical exam, magnetic resonance imaging, computed tomography, and positron emission tomography. Chemoradiation remains the mainstay of treatment for most patients, with surgery reserved for salvage therapy. Recent trials have identified the optimal use of available chemotherapeutics. Exciting developments in immune therapies targeting HPV oncoproteins as well as therapeutic vaccines may soon dramatically change the way patients with anal cancer are managed.