Peritoneal Metastases: Prevention and Treatment

Selection Factors for Treatment and Stratification of Rare Abdominal or Pelvic Tumors with Peritoneal Metastases

To maximize the results of treatments for peritoneal metastases for rare abdominal or pelvic tumors, selection of patients with a possibility for long-term success is necessary. Because these malignancies are rare, data from which these selection factors can be extracted do not exist. In order to facilitate knowledgeable patient selection for treatment, the well established clinical and histopathologic features of the common malignancies treated for peritoneal metastases were reviewed. The potential application of selection factors for common diagnoses was explored in an attempt to provide selection factors for rare tumors. The histopathologic grade, the lymph node status, the Ki-67 proliferation index, prior surgical score (PSS), preoperative radiologic imaging, preoperative laparoscopic assessment, response to neoadjuvant chemotherapy, peritoneal cancer index (PCI), and completeness of cytoreduction score were all included in this search for relevant selection factors for a rare disease. To facilitate the use of selection factors from common peritoneal metastases diagnoses, these diseases were divided into four groups. Placement of the rare cause of peritoneal metastases into one of these four groups will allow knowledgeable selection for treatment. Rare diseases with a natural history resembling low-grade appendiceal neoplasms are in group 1, diseases resembling lymph node negative colorectal cancer are in group 2, diseases resembling lymph node positive colorectal peritoneal metastases in group 3, and diseases resembling gastric cancer in group 4.

Enhanced recovery after surgery promotes the postoperative recovery of lung and gastrointestinal function of pseudomyxoma peritonei

OBJECTIVES

Pseudomyxoma peritonei (PMP) is a rare low-grade malignant tumor, which is difficult to operate with many postoperative complications. In recent years, enhanced recovery after surgery (ERAS) has been greatly developed in the perioperative management of surgical diseases, and it plays an important role in improving the postoperative prognosis of surgical patients. This study was conducted to explore the application of ERAS in the perioperative management of PMP patients, and to study the effect of ERAS on postoperative respiratory and digestive tract complications.

METHODS

We retrospectively analyzed clinical data of patients with PMP from January 2014 to December 2018. These patients were treated with surgery in our center and they were divided into an observation group and a control group. The patients in the control group didn't perform ERAS in perioperative period, and patients in the observation group was performed ERAS. Then, we analyzed and compared the postoperative pulmonary complications (PPC) and gastrointestinal function between the 2 groups.

RESULTS

There was no significant difference in the incidence of atelectasis, pleural effusion, pulmonary infection and acute respiratory distress syndrome (ARDS) between the two groups, but the total incidence of PPC in the observation group was significantly lower than that in the control group (P=0.032). The incidence of postoperative gastrointestinal dysfunction (PGID) in the observation group was significantly lower than that in the control group (P=0.025), and the postoperative first exhaust time, first defecation time, oral feeding time, and albumin level in the observation group were all better than those in the control group (all P<0.05).

CONCLUSIONS

ERAS can significantly reduce the incidence of postoperative PPC and PGID in the PMP patients and improve their postoperative recovery.

Case Report: First in Human Online Adaptive MR Guided SBRT of Peritoneal Carcinomatosis Nodules: A New Therapeutic Approach for the Oligo-Metastatic Patient

Peritoneal carcinosis (PC) is characterized by poor prognosis. PC is currently treated as a locoregional disease and the possibility to perform very precise treatments such as stereotactic body radiation therapy (SBRT) has opened up new therapeutic perspectives. More recently, the introduction of Magnetic Resonance-guided Radiation Therapy (MRgRT) allowed online adaptation (OA) of treatment plan to optimize daily dose distribution based on patient’s anatomy. The aim of this study is the evaluation of the effectiveness of SBRT OA workflow in an oligometastatic patient affected by PC. We report the clinical case of a patient affected by PC originating from colon cancer, previously treated with chemotherapy and surgery, addressed to OA SBRT treatment on a single chemoresistant PC nodule, delivered with a 0.35 T MR Linac. Treatment was delivered using gating approach in deep inspiration breath hold condition in order to reduce intrafraction variability. Prescription dose was 35 Gy in 5 fractions. The PTV V95% of the original plan was 96.6%, while the predicted values for the following fractions were 11.9, 56.4, 0, 0, and 61%. Similarly, the small bowel V19.5 Gy of the original plan was 4.63 cc, while the predicted values for the following fractions were 3.7, 8.6, 10.7, 1.96, 3.7 cc. Thanks to the OA approach, the re-optimized PTV V95% coverage improved to 96.1, 89.0, 85.5, 94.5, and 94%; while the small bowel V19.5 Gy to 3.36; 3.28; 1.84; 2.62; 2.6 cc respectively. After the end of RT, the patient was addressed to follow-up, and the re-evaluation ¹⁸F-FDG PET-CT was performed after 10 months from irradiation showed complete response. No acute or late toxicities were recorded. MRgRT with OA approach in PC patients is technically and clinically feasible with clean toxicity result. Online adaptive SBRT for oligometastases opens up new therapeutic scenarios in the management of this category of patients.

Curative versus palliative treatments for colorectal cancer with peritoneal carcinomatosis: a systematic review and meta-analysis

The objective of this study was to provide an up-to-date summary of the current evidence that may be useful for updating guidelines. We comprehensively searched the published literatures and conferences for studies that compared curative with palliative treatments in colorectal cancer patients with peritoneal metastasis. The primary outcomes considered in this study were three- and five-year overall survival rates. We pooled data across studies and estimated summary effect sizes. Overall, patients who received curative treatments had improved three-year survival (hazard ratio (HR), 2.19 [95% CI, 1.83 to 2.62]) and five-year survival (HR, 2.22 [95% CI, 1.83 to 2.69]) compared with those who received palliative treatments. Patients who received curative treatments had an increased risk of treatment-related morbidity (odds ratio (OR), 2.90 [95% CI, 2.02 to 4.17]), but there was no significant difference in treatment-related mortality between patients who received curative treatments and those who received palliative treatments (OR, 1.46 [CI, 0.62 to 3.47]). Curative treatments improved overall survival in colorectal cancer patients with peritoneal metastasis and did not increase the risk of treatment-related mortality. Curative treatments were associated with a higher risk of treatment-related morbidity. These data highlight the importance for further investigation aimed at prevention of treatment-associated morbidity.