Education and Training in Peritoneal Surface Oncology.

Peritoneal surface oncology (PSO) is a novel field dealing with the knowledge of peritoneal neoplasms, primary or secondary, and their clinical management. As a specific treatment with curative intent for peritoneal neoplasms developed over the years, there is a growing need to comprehensively educate and train surgical oncologists worldwide in this discipline, a recognized unmet need. The European School of Peritoneal Surface Oncology (ESPSO) emerged in 2014 to provide an answer to this need.

Critical appraisal of total gastrectomy plus total colectomy with hyperthermic intraperitoneal chemotherapy as a treatment for advanced pseudomyxoma peritonei.

BACKGROUND: The absolute requirement for a long-term favorable result with cytoreductive surgery for pseudomyxoma peritonei is a complete resection of all visible disease. A combination of parietal peritonectomy procedures and visceral resections is required for this to occur. The cytoreductive surgery is supplemented by hyperthermic intraperitoneal chemotherapy. METHODS: We searched our database and secured files for patients who required a total gastrectomy and a total colectomy to achieve a complete cytoreductive surgery. Survival of low-grade mucinous neoplasm (LAMN) and mucinous appendiceal adenocarcinoma (MACA) histologies were determined. Clinical and histologic variables were assessed for their impact on survival. RESULTS: Thirteen of 450 patients (2.9%) with LAMN histology and 14 of 186 patients (7.5%) with MACA histology had these visceral resections. Median survival of these 27 patients was 10 years. LAMN and MACA patients showed the same survival. For LAMN histology, this requirement for extensive visceral resection markedly reduced survival (p < 0.0001). For MACA, there was no adverse impact on survival (p = 0.4359). Class 4 adverse events caused reduced survival (p = 0.0014). CONCLUSIONS: A 10-year median survival accompanies total gastrectomy plus total colectomy for advanced pseudomyxoma peritonei. Systemic chemotherapy and class 4 adverse events reduced survival.

Critical reappraisal of prognostic indicators for 949 mucinous appendiceal neoplasm patients.

BACKGROUND AND OBJECTIVES: The standard of care for treatment of an appendiceal mucinous neoplasm with peritoneal dissemination is cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC). These two treatments are combined in the operating room. A crucial requirement for benefit long-term is proper patient selection. Clinical and histopathologic prognostic indicators are used, along with the patient's fitness for surgery, to select patients to receive CRS and HIPEC. METHODS: This study seeks to identify the reliable prognostic indicators for four different groups of patients. They are (1) the low-grade appendiceal mucinous neoplasms (LAMN) with a complete CRS, (2) the mucinous appendiceal adenocarcinomas (MACA) with complete CRS, (3) MACA with lymph node metastases (MACA-LN) with complete CRS, and (4) all histologic subtypes with incomplete cytoreduction. The prognostic indicators were evaluated for their impact on overall survival in these four groups of patients. RESULTS: The completeness of cytoreduction (CC) score statistically significantly showed survival differences in all three histologic subtypes. The peritoneal cancer index (PCI) showed significance with LAMN and MACA-LN but not with MACA and not with incomplete CRS. The prior surgical score (PSS) was a prognostic indicator that predicted the outcome with LAMN, MACA-LN, and incomplete CRS patients but not with the MACA group. Patients who were symptomatic or who had extensive systemic chemotherapy before CRS had a significantly reduced survival. CONCLUSION: The utility of prognostic indicators varied greatly within our four different groups of appendiceal mucinous neoplasms. CC score was always a reliable prognosticator. Surprisingly, PCI was not.

Cellularity of mucus is a prognostic variable in low-grade appendiceal mucinous neoplasms.

For peritoneal metastases from a primary appendiceal mucinous neoplasm to exist, the thin wall of the appendix must perforate to allow mucus or mucus plus tumor cells to gain access to the peritoneal spaces. The proportion of specimens containing tumor cells within mucus as compared to mucus only outside the appendix may have prognostic significance. The histopathology of tumor masses was determined from the specimens resected at the cytoreductive surgery (CRS). The presence versus absence of tumor cells in mucus and the proportion of specimens with tumor cells was determined and correlated with the overall survival of these patients. In 418 patients with a complete cytoreduction for a low-grade appendiceal mucinous neoplasm (LAMN), the cellularity of all resected specimens was determined. The hazard ratio of overall survival of patients whose specimens had no cells as compared to specimens with cells in mucus by histology was 4.41 (1.61, 12.1) (p = 0.0039). If overall survival of patients with all specimens without tumor cells was compared to patients with specimens with 1-99 % tumor and compared to patients with 100 % of specimens with tumor cells, the hazard ratios were 4.3 (1.34, 13.8) (p = 0.0143) and 9.62 (2.93, 31.6) (p = 0.0002), respectively. The cellularity of mucus within the specimens removed by a complete CRS has strong prognostic implications in LAMN patients. LAMN with acellular specimens (LAMNa) as compared to LAMN with tumor cells in specimens (LAMNb) should be staged as different histologic subtypes of mucinous appendiceal neoplasms.

It Is What the Surgeon Does Not See That Kills the Patient.

BACKGROUND: Patients with colon cancer may present at multiple different stages of the disease process. Many patients can be cured of colon cancer as a result of a simple surgical procedure usually performed by minimally invasive techniques. However, there are a variable number of patients, estimated at approximately 10%, who have a more advanced disease. If these patients are treated by the current conventional standard of care, the likelihood for treatment failure is extremely high. METHODS: These are not patients with known disseminated disease but patients who are at high risk of recurrent disease unless special treatments are initiated preoperatively and intraoperatively. The identification of these patients is by (1) a high-quality CT scan, (2) tumor markers found preoperatively, (3) colonoscopic findings, and (4) symptoms. RESULTS: Patients identified as being at high risk require special preoperative treatments which include neoadjuvant chemotherapy. Intraoperative chemotherapy with HIPEC should occur as part of the treatment if peritoneal metastases are documented by biopsy. In the operating room, a thorough exploration of all possible occult peritoneal spaces for metastatic disease needs to be performed. A modified cytoreductive surgical procedure along with a colon resection is performed in order to minimize sites of occult peritoneal metastases. This includes the greater omentum, ovaries, and tubes in postmenopausal women. Peritonectomy is used to create a shroud around the tumor so that all peritoneum that has been in direct contact with the tumor surface is resected and is used as a barrier against tumor cell dissemination in the process of colon cancer resection. If peritoneal metastases are visualized at any site, HIPEC should be included as part of the treatment package. CONCLUSIONS: I am convinced that patients at high risk of recurrence will have an improved outcome with proper preoperative evaluation, preoperative neoadjuvant chemotherapy, and a revised intraoperative management strategy.

Phase 1 trial of same day cytology to guide the use of HIPEC.

Background: Peritoneal metastases from gastrointestinal or gynecologic malignancy are a prominent part of the natural history of these diseases. Peritoneal metastases, if not effectively treated, will result in a decreased survival and cause an impaired quality of life. Hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment specifically designed to combat peritoneal metastases. A group of patients who, from a theoretical perspective, may benefit from HIPEC are those patients with a positive peritoneal cytology. In order to identify these patients at the time of a surgical intervention, a same day cytology is to be performed. Materials and methods: The result of this test is to be available at or before the completion of the cancer resection. If the cytology is positive, the patient immediately becomes a candidate for HIPEC. The HIPEC will be of maximal value if a complete cytoreduction, as judged by the surgeon, has been possible. This phase 1 trial is to demonstrate that the Surgical Oncology Service, the Department of Pathology, the Pharmacy and the Operating Room personnel can co-ordinate a phase 1 protocol to successfully complete the same day cytology with an efficient delivery of HIPEC. A standardized plan for consent, cytology collection, preparation of the specimen, reading of the specimen, reporting the results in a timely manner facilitates the administration of HIPEC in peritoneal cytology positive patients. Dissemination: Successful completion of these requirements is a positive result for this study and allows for future protocols to be generated. Successful completion of the same day cytology phase 1 protocol will allow the efficacy, safety, and efficiency of this plan of patient management to be evaluated.

Use of early postoperative intraperitoneal 5-fluorouracil with index cytoreduction improves survival with secondary cytoreductive surgery.

BACKGROUND: In patients with appendiceal mucinous neoplasm with peritoneal dissemination, a cytoreductive surgery (CRS) with perioperative chemotherapy may result in long-term survival. Disease progression may require secondary cytoreductive surgery (SCRS) and other treatments in selected patients to improve survival and preserve an optimal quality of life. METHODS: The clinical- and treatment-related variables associated with the index CRS and SCRS were statistically assessed for impact on survival after SCRS. RESULTS: A total of 186 of 687 complete CRS patients (27.1%) had SCRS. Median follow-up was 10 years and median survival was 12 years. In 95 males (51%) the median age was 45.0 years. Survival benefit with SCRS was observed if early postoperative intraperitoneal chemotherapy (EPIC) with 5-fluorouracil (EPIC 5-FU) or hyperthermic intraperitoneal chemotherapy (HIPEC) plus EPIC 5-FU was used with the index CRS (hazard ratio [HR]: 0.6, p = 0.0360; HR: 0.4, p = 0.0004, respectively). By propensity matching of 51 pairs of patients, EPIC 5-FU used with index CRS caused a survival advantage compared to HIPEC alone (p = 0.0100) with index CRS (p = 0.0100). CONCLUSIONS: Use of EPIC 5-FU at a complete index CRS was a prognostic variable that improved survival in patients requiring SCRS. Further investigations into the benefits of antiadhesion treatments with CRS and HIPEC are warranted.

Randomized trial of intravenous versus bidirectional chemotherapy after cytoreductive surgery for malignant peritoneal mesothelioma.

Background: Malignant peritoneal mesothelioma (MPM) is a rare disease that progresses within the peritoneal cavity and only disseminates to systemic sites in the terminal months of the disease. For this malignancy, there are several regimens of chemotherapy that have been accepted as standard, principally intraperitoneal chemotherapy (IPC) and intravenous chemotherapy (IVC); however, there is no standardized method of treatment. Selected patients with MPM who are amenable to cytoreductive surgery (CRS) and are fit for surgery typically undergo resection with hyperthermic intraperitoneal chemotherapy (HIPEC). Though individual toxicity and efficacy studies of IPC plus IVC (bidirectional) and IVC chemotherapy for MPM have been conducted, a prospective randomized clinical trial has not been performed for this disease. Materials and methods: The study objective is to compare the efficacy and toxicity of normothermic bidirectional (IPC/IVC) chemotherapy versus IVC after CRS and HIPEC for epithelial MPM. The patient population are those individuals undergoing CRS for MPM. Exclusion criteria include previous therapy form mesothelioma. The study design is a randomized, nonblinded, phase II clinical trial comparing multicycle IVC with cisplatin (CDDP) and pemetrexed (PMTX) versus multicycle bidirectional chemotherapy with IVC CDDP and IPC PMTX after optimal CRS and HIPEC with CDDP and doxorubicin. The primary endpoint is 2-year disease-free survival. The secondary endpoint is 30-day post-treatment morbidity. The primary objective is to compare the 2-year rates of disease-free survival in the two treatment arms. The secondary objective is to compare the toxicity of each treatment. Dissemination: The prospective randomized trial provides not only a standardized approach to treatment but also a path forward to optimize the survival of patients with MPM. In addition, any increase or decrease in the adverse events associated with PMTX administered as IPC will be demonstrated. Because MPM is a rare disease a multi-institutional implementation of the protocol is required.