Peritoneal Carcinomatosis of Urachus Origin Treated by Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (HIPEC): An International Registry of 36 Patients

Pseudomyxoma Peritonei Arising from Urachal Mucinous Neoplasms: a Case Series and Updated Literature Review

To report a case series of patients with pseudomyxoma peritonei (PMP) from urachal mucinous neoplasm (UMN) treated with CRS and HIPEC at a high-volume referral centre, along with an updated literature review. Retrospective review of cases treated between 2000 and 2021. A literature review using MEDLINE and Google Scholar databases was performed. Clinical presentation of PMP from UMN is heterogeneous, and common symptoms are abdominal distension, weight loss, fatigue and haematuria. At least one tumour marker among CEA, CA 19.9, and CA 125 was elevated in the six cases reported, and 5/6 had a preoperative working diagnosis of urachal mucinous neoplasm suspected on detailed cross-sectional imaging. Complete cytoreduction was achieved in five cases, while one patient underwent maximal tumour debulking. Histological findings mirrored the findings of PMP from appendiceal mucinous neoplasms (AMN). Overall survival ranged between 43 and 141 months after complete cytoreduction. On literature review, 76 cases have been reported to date. Complete cytoreduction is associated with good prognosis for patients with PMP from UMN. A definitive classification system is still not available.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13193-022-01694-5.

Peritoneal Surface Malignancies Originating From Urachal Carcinoma: Case Reports and Review of the Literature

Urachal carcinoma (UC) is a rare and aggressive tumor arising from the urachal remnants, with the potential for peritoneal dissemination. Patients diagnosed with UC often have a poor prognosis. To date, there is no standardized treatment. Our objective is to present two cases of patients with peritoneal carcinomatosis (PC) secondary to an UC, who were treated with cytoreductive surgery (CRS) and hyperthermic peroperative intraperitoneal chemotherapy (HIPEC). A review of the literature on CRS and HIPEC in UC suggests CRS and HIPEC to be a safe and viable treatment option. Two patients with PC of UC underwent CRS and HIPEC in our institution. All available data were gathered and reported on. A literary search was carried out to find all available cases of patients with PC secondary to UC treated with CRS and HIPEC. Both patients underwent CRS and HIPEC and are currently free of recurrence. Literature research revealed nine other publications adding up to a total of 68 additional cases. CRS and HIPEC can provide satisfactory long-term oncological outcome with acceptable morbidity and mortality rates in patients with PC of urachal origin. It should be considered as a safe and feasible treatment option with curative potential.

The Diagnostic Value of FDG-PET/CT for Urachal Cancer

BACKGROUND

Urachal carcinoma (UrC) is a rare malignancy that often presents at an advanced stage with metastases in up to a quarter of patients. There is no consensus on the optimal form of staging for patients with UrC. In the present study, we evaluated the diagnostic value of ¹⁸F-fluorodeoxyglucose-positron emitted tomography/computed tomography (FDG-PET/CT) for UrC.

PATIENTS AND METHODS

We evaluated 40 consecutive patients who were staged for urachal cancer between 2010 and 2020. They underwent a total of 62 FDG-PET/CTs (40 for primary staging, and 22 during follow-up), which were compared with standard-of-care contrast-enhanced CT (CECT). The metabolic detection of primary tumors, lymph node metastases (LNMs), peritoneal metastases (PMs), distant metastases (DMs), and local recurrence by FDG-PET/CT was evaluated. Sensitivity and specificity were calculated compared with CECT. Histopathology or follow-up imaging was the reference standard.

RESULTS

Of all 40 patients, 33 patients (83%) had urachal adenocarcinoma-26 (65%) with a mucinous component and 7 (17%) with invasive urothelial carcinoma. All local UrC tumors could be visualized on CT, and 80% showed increased FDG uptake. At initial staging, FDG-PET/CT detected FDG-avid LNMs, PMs, and DMs in 50%, 17%, and 25% of patients, respectively. These metastases were also visualized on CECT. During follow up, FDG-PET/CT revealed FDG-avid local recurrences that were not seen on CT in two out of eight patients (25%).

CONCLUSION

The present study demonstrates that most UrC can be visualized on FDG-PET/CT. At initial diagnosis, FDG-PET/CT does not seem to yield additional information compared with CECT; however, FDG-PET/CT may be helpful during follow-up. This is a small study, and the findings should be corroborated with larger series.

Evaluation of the significance of pseudomyxoma peritonei patients based on the Peritoneal Surface Oncology Group International (PSOGI) classification

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare disease characterized by mucinous ascites and deposits on the peritoneal surfaces. The study aimed to assess PMP patients according to the Peritoneal Surface Oncology Group International (PSOGI) classification, as a part of standardization of this rare disease.

METHODS

This retrospective study analyzed PMP patients who underwent surgery between January 2007 and December 2017. All histologic slides were re-evaluated and the clinical data were collected. According to the PSOGI, PMP was retrospectively classified into three categories: low-grade (LG-PMP), high-grade (HG-PMP), and signet-ring cells (SRC-PMP). The extent of peritoneal involvement was quantified by the peritoneal cancer index (PCI). The completeness of cytoreduction (CCR) was dichotomized as complete or incomplete.

RESULTS

Fifty-seven patients were included in this study, consisted of 39 patients with LG-PMP (74.0%), 14 with HG-PMP (20.8%), and 4 with SRC-PMP (5.2%). There was no operative mortality and major complications occurred in 24 patients (31.2%). The 5-year overall survival was 56.2% ± 8.1% for LG-PMP, 37.5% ± 12.1% for HG-PMP, and 25.0% ± 21.7% for SRC-PMP. Concerning CCR, the 5-year overall (complete: 59.5% ± 8.4% vs. incomplete: 12.7% ± 8.1%, p = 0.001) and disease-free survival (complete: 38.6% ± 8.9% vs. incomplete: 7.7% ± 6.8%, p = 0.001) were significantly different. In a multivariable analysis, PSOGI classification and CCR independently correlated with survival (p = 0.011 and 0.018, respectively).

CONCLUSIONS

The PSOGI classification provides prognostic stratification, hopefully requiring further validation including every single case of PMP established as a standard criteria.

Diagnostic Laparoscopy and Abdominal Cytology Reliably Detect Peritoneal Metastases in Patients with Urachal Adenocarcinoma

BACKGROUND

Urachal adenocarcinoma (UrAC) is a rare malignancy that can cause peritoneal metastases (PM). Analogous to other enteric malignancies, selected patients with limited PM of UrAC can be treated by cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC).

OBJECTIVE

The aim of this study was to address the value of diagnostic laparoscopy (DLS) and abdominal cytology (ACyt) for the detection and evaluation of the extent of PM in patients with UrAC.

METHODS

A consecutive series of cN0M0 patients with UrAC who underwent DLS with or without ACyt at a tertiary referral center between 2000 and 2018 was assessed. Patients were staged with computed tomography (CT) and/or positron emission tomography (PET)/CT or bone scan. DLS was performed to rule out PM and to evaluate the extent and resectability of PM if seen on imaging. Sensitivity and specificity values were calculated for imaging, DLS, ACyt, and the combination of DLS and ACyt.

RESULTS

Thirty-two patients with UrAC underwent DLS. ACyt was obtained in 19 patients. Four patients had suspicion of PM on imaging. In the 28 patients who were PM-negative on imaging, DLS and ACyt revealed PM in 6 (21%) patients, of whom 5 had macroscopically visible PM; 1 patient had positive ACyt without visible PM. Sensitivity of combined DLS/ACyt for the detection of PM was 91%, with a specificity of 100%, whereas sensitivity of imaging was 36%. DLS correctly predicted resectability in all patients.

CONCLUSION

Combined DLS/ACyt proved an effective tool to detect occult PM and to evaluate the extent of PM to select UrAC patients for possible treatment with CRS/HIPEC.

An update of peritonectomy procedures used in cytoreductive surgery for peritoneal malignancy

Background: Complete cytoreduction is acknowledged to be an effective way to achieve macroscopic tumor clearance for a variety of tumors confined to the peritoneal cavity. Recent trials have shown that surgery respecting anatomical planes results in excellent outcomes and even the chance of cure for some from what was once thought to be life-limiting disease. Objective: To describe peritonectomy procedures in the current era. Method: A thorough and systematic method for cytoreductive surgery aimed at complete surgical resection of peritoneal metastases (PMs) was described. Results: The general principles of cytoreductive surgery were set out including preoperative preparation, patient positioning and incision. Strategies for assessing disease extent and planning surgical steps were outlined and established peritonectomy procedures such as Glisson's capsulectomy, omentectomy, left and right diaphragmatic peritonectomy, lesser omentectomy, stripping of the omental bursa, and pelvic peritonectomy were described. Novel techniques such as anterior pancreatic peritonectomy, small bowel mesenteric peritonectomy and cardiophrenic lymph node dissection were explained, and illustrated with accompanying video. Conclusion: Peritoneal metastases present a challenge to the surgeon which calls for a unique skill set if optimal outcomes are to be achieved. Attempts to standardize the surgical techniques described will allow further refinement as new technological advances occur.

Recurrence of pseudomyxoma peritonei after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

Background

Pseudomyxoma peritonei (PMP) is a rare clinical condition characterized by mucinous ascites, typically related to appendiceal or ovarian tumours. Current standard treatment involves cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), but recurrences occur in 20–30 per cent of patients. The aim of this study was to define the timing and patterns of recurrence to provide a basis for modifying follow‐up of these patients.

Methods

This observational study examined a prospectively developed multicentre national database (RENAPE working group) to identify patients with recurrence after optimal CRS and HIPEC for PMP. Postoperative complications, long‐term outcomes and potential prognostic factors were evaluated.

Results

Of 1411 patients with proven PMP, 948 were identified who had undergone curative CRS and HIPEC. Among these patients, 229 first recurrences (24·2 per cent) were identified: 196 (20·7 per cent) occurred within the first 5 years (early recurrence) and 30 (3·2 per cent) occurred between 5 and 10 years. Three patients developed a first recurrence more than 10 years after the original treatment. The mean(s.d.) time to first recurrence was 2·36(2·21) years. Preoperative chemotherapy and high‐grade pathology were significant factors for early recurrence. Overall survival for the entire group was 77·9 and 63·1 per cent at 5 and 10 years respectively. The principal site of recurrence was the peritoneum.

Conclusion

Recurrence of PMP was rare after 5 years and exceptional after 10 years.

Urachal Adenocarcinoma: A Case Report with Key Imaging Findings and Radiologic-Pathologic Correlation

Urachal pathologies are rare and can mimic numerous abdominal and pelvic diseases. Differential diagnosis of urachal anomalies can be narrowed down by proper assessment of lesion location, morphology, imaging findings, patient demographics, and clinical history. We report a case of a 60-year-old male, with a history of unintentional weight loss without associated symptoms, who was diagnosed with locally invasive urachal adenocarcinoma. With this article, we pretend to emphasize urachal adenocarcinoma clinical features along with its key imaging findings with radiologic-pathologic correlation.