Laparoscopic abdominoperineal resection for the treatment of a mucinous adenocarcinoma associated with an anal fistula

Surgical management of mucinous adenocarcinoma arising in perianal fistula: A case series

Perianal mucinous adenocarcinoma (MAC) is a rare malignancy arising in the anal canal, often associated with chronic inflammatory conditions such as perianal fistulas. This case series aims to elucidate the clinical features and surgical management of patients with perianal MAC arising from perianal fistulas. Four cases of perianal MAC are presented, highlighting the diverse clinical presentations, diagnostic pathways, and therapeutic interventions. Each case demonstrates unique aspects of disease progression, treatment response, and long-term outcomes. Key features include the challenges of diagnosing MAC amidst benign conditions, the role of neoadjuvant chemotherapy in improving resectability, and the importance of individualized surgical approaches. All patients were male and presented with a variety of symptoms ranging from changes in bowel habits to perianal abscesses. The diagnosis was challenging due to the resemblance of MAC to benign conditions and delayed presentation. All patients underwent abdominoperineal resection (APR) and colostomy insertion (perineal or abdominal). Two cases required reconstructive procedures where a V-Y flap and an omental flap were employed. A multidisciplinary approach ensures that patients receive appropriate neoadjuvant and adjuvant treatment. With the median follow-up of 3 years, all patients were alive. Our multidisciplinary approach effectively managed perianal MAC by integrating surgical techniques, including APR and reconstructive methods, along with neoadjuvant and adjuvant treatment. Performing appropriate surgical techniques leads to tumor-free margins, in addition to systemic therapy, and improves both patient survival and quality of life.

"Budding"-an early MRI feature established in a case-control study of perianal fistula mucinous adenocarcinoma

Background

Perianal fistula mucinous adenocarcinoma (FMA) usually presents at an advanced stage, necessitating extensive surgical resection. Symptoms of perianal pain and discharge are indistinguishable from fistula sepsis. Absence of defined features on magnetic resonance imaging (MRI) precludes early diagnosis. This study aims to validate MRI features that should increase suspicion of early mucinous transformation, prompting urgent examination and targeted biopsies.

Methods

Retrospective review of MRI studies was conducted in 9 patients with FMA in Crohn's perianal and non-Crohn's ileoanal pouch fistula between 2015-2019. Radiological features were assessed. Fine T2-weighted high signal lobulation of the fistula tract on MRI, described as 'budding', was retrospectively noted on historic studies in all cases of FMA and was determined a feature distinct from expected T2-weighted high signal appearance of bland fistula sepsis. The significance of these features in early diagnosis of FMA was assessed using a case control study.

Results

'Budding', mass-like expansion of the tract, and septation of T2-weighted high signal components of the fistula were significantly associated with FMA using Fisher's exact test (P<0.001). The presence of T2-weighted high signal "budding" predated the histological confirmation of FMA by a median 36 months (range, 12-156 months). One control patient was diagnosed with FMA during the study as 'budding' was retrospectively detected, triggering urgent targeted biopsy.

Conclusions

Radiological awareness of early features of FMA may improve outcomes by reducing the morbidity of exenterative surgery with delayed diagnosis. The presence of T2-weighted high signal 'budding' on MRI should prompt urgent targeted biopsy.

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.

Laparoscopic abdominoperineal resection and myocutaneous flap reconstruction for anal fistula cancer arising from complicated anal fistula: two case reports

BACKGROUND

Anal fistula cancer is rare and definitive treatment has not yet been established. Laparoscopic abdominoperineal resection is generally the first choice of treatment if the cancer is determined to be resectable. However, complicated anal fistula cancer often requires extensive resection. Using a myocutaneous flap for reconstruction after resection in such cases, radical resection can be performed regardless of the size of the anal fistula cancer.

CASE PRESENTATION

We report two cases in which we performed laparoscopic abdominoperineal resection with extensive buttock resection and myocutaneous flap reconstruction for widespread anal fistula cancer. One of the cases was reconstruction with a posterior thigh flap, the other was with a bilateral expanded gluteus maximus flap. Both cases were anal fistula cancers that developed from complicated anal fistulas.

CONCLUSIONS

If the size of anal fistula cancer is large and extended buttock resection is necessary, radical resection of anal fistula cancer is possible using myocutaneous flap for reconstruction after extended abdominoperineal resection.

Perianal Mucinous Adenocarcinoma Found Incidentally From Perianal Mass

Anal mucinous adenocarcinomas are very rare and usually arise from anal fistulas. We report a case of a 73-year-old man with a past medical history of hypertension admitted to our facility for evaluation of bleeding from a large, tender, left gluteal perianal mass. The patient reported the mass had been growing for over six years. On examination, an ulcerated, fungating large exophytic lesion was found extending from the anal verge laterally engulfing the left gluteus. The patient was anemic with low hemoglobin and hematocrit, as well as an elevated carcinoembryonic antigen level. A colonoscopy was performed during which an internal opening of a left-sided anal fistula was identified. The mass was biopsied and returned positive for a mucinous adenocarcinoma. Staging imaging including a computed tomography scan of the chest abdomen and pelvis did not show any metastatic disease. A magnetic resonance image of the pelvis revealed a locally invasive, heterogeneous tumor extending from the perianal soft tissue to the posterior wall of the anal canal and lower rectum. The patient was discussed at the interdisciplinary tumor board and completed five weeks of concurrent chemotherapy and radiation with 5-fluorouracil and a total of 28 fractions of radiation. He then underwent abdominoperineal resection with a vertical rectus abdominis myocutaneous flap. The patient was placed in the surgical intensive care unit and subsequently discharged in stable condition on postoperative day 14. This case highlights the presentation, diagnosis, and management of anal mucinous adenocarcinoma.

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.

Magnetic resonance imaging findings of carcinoma arising from anal fistula: A retrospective study in a single institution

BACKGROUND

Magnetic resonance imaging (MRI) is currently the standard investigation for suspected perianal diseases. Carcinoma arising from anal fistula is very rare, and early diagnosis is often difficult.

AIM

To describe and summarize the MRI findings of carcinoma arising from anal fistula.

METHODS

In this retrospective study, records of ten patients diagnosed with carcinoma arising from anal fistula and confirmed by surgery (n = 7) or biopsy (n = 3) between June 2006 and August 2018 were analyzed. All patients underwent preoperative pelvic MRI. Morphologic features, signal characteristics, fistula between the mass and the anus, contrast enhancement of mass, signal and enhancement of peritumoral areas, and regional lymphadenopathy were assessed.

RESULTS

All ten tumors were solitary (8 mucinous adenocarcinomas and 2 adenocarcinomas). The maximum diameter of the tumors ranged from 3.4 cm to 12.4 cm (median: 4.15 cm; mean: 5.68 cm). Eight patients had a fistula between the mass and the anus. Contrast enhancement of the peritumoral areas was noted in three (3/5) patients. Perirectal or inguinal lymphadenopathy was noted in seven patients. Most lesions of mucinous adenocarcinoma were multiloculated and cauliflower-like, with a thin capsule and focally unclear boundary. They were markedly hyperintense on fat-suppressed T2WI, slightly hyperintense with focal hyperintensity on diffusion-weighted imaging (DWI), and hyperintense with focal hypointensity on apparent diffusion coefficient (ADC) map, with progressive mesh-like contrast enhancement. Adenocarcinomas had an infiltrative margin without a capsule and appeared heterogeneously hyperintense or slightly hyperintense on fat-suppressed T2WI, hyperintense on DWI, and hypointense on ADC map, with persistent heterogeneous enhancement.

CONCLUSION

Our study highlighted several characteristic and potentially helpful MRI findings to diagnose carcinomas arising from anal fistula.

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.

Novel role of NLRP3-inflammasome in regulation of lipogenesis in fasting-induced hepatic steatosis

Background: The liver coordinates a series of metabolic adaptations to maintain the energy balance of the system and provide adequate nutrients to key organs, tissues and cells during starvation. However, the mediators and underlying molecular mechanisms that mediate these fasting-induced adaptive responses remain unclear. Materials and methods: Male wild-type C57BL/6J littermates (8-weeks-old) were intraperitoneally injected with MCC950 or vehicle, and then randomly divided into three groups: fed, fasted, and refed. Plasma IL1β and insulin levels were detected by ELISA kits. Plasma and hepatic metabolites were determined using commercial assay kits. HepaRG cell line was applied to verify the regulation of NLRP3 on lipogenesis. Results: NOD-like receptor protein 3 (NLRP3) and its downstream inflammatory cytokines were significantly suppressed after 24 h fasting and recovered upon 6 h refeeding in plasma and liver tissues of mice. Moreover, fasting-induced hepatic steatosis and accompanied liver injury were ameliorated when mice were intraperitoneally injected with MCC950 (a selective NLRP3 inhibitor). Further study revealed that MCC950 suppressed sterol regulatory element-binding protein-1c (SREBP-1c) expression and transcriptional activity, thus inhibited lipogenesis in the liver, which may explain its role in stabilizing lipid metabolism. Conclusion: The NLRP3 inhibitor-MCC950 protects against fasting-induced hepatic steatosis. The novel and critical role of NLRP3 in lipogenesis may explain its importance in regulating the adaptive responses of the liver upon starvation stress and may provide therapeutic value.