Revised prognostic indicators for treatment of lymph node positive colorectal peritoneal metastases

Preoperative chemotherapy response and survival in patients with colorectal cancer peritoneal metastases

Treatment guidelines provided by PRODIGE-7 recommend perioperative systemic chemotherapy before cytoreductive surgery (CRS) for colorectal cancer peritoneal metastases (CRPM). Toxicity with multimodal treatment needs to be better defined. Chemotherapy response and impact on survival have not been reported. We assessed CRPM patients who received systemic oxaliplatin/irinotecan before CRS (preoperative) with Mitomycin C (35 mg/m2, 90 min) or Oxaliplatin (368 mg/m2, 30 min) heated intraperitoneal chemotherapy (HIPEC). Secondary analysis was performed from a prospective database. Overall survival (OS) in chemotherapy responders (R) and nonresponders (NR) was compared. Toxicity was assessed by rate of adverse events (AEs). From April 2005 to April 2021, 436 patients underwent CRS + HIPEC; 125 (29%) received preoperative chemotherapy. The 112 (90%) received oxaliplatin (64, 57%) or irinotecan (48, 43%). R, defined as complete (CR) or partial response on preoperative imaging and/or postoperative histology, was seen in 71, 63% (53.8-72.3); 16, 14% (8.4-22.2) had CR. Median OS in R versus NR was 43.7 months (37.9-49.4) versus 23.9 (16.3-31.4) p = 0.007, HR 0.51 (0.31-0.84). OS multivariable analysis showed HR 0.48 (0.25-0.95), p = 0.03 for chemotherapy response corrected by peritoneal cancer index, completeness of cytoreduction score. CRS led to 21% grade 3-4 AEs versus 4% for preoperative chemotherapy. HIPEC grade 3-4 AEs were 0.5%. Preoperative chemotherapy response is an independent predictor for OS in CRPM.

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.

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.

Response to Nivolumab followed by complete cytoreductive surgery with HIPEC resulted in long-term survival in a patient with sarcomatoid-predominant biphasic peritoneal mesothelioma. A case report

INTRODUCTION AND IMPORTANCE

Sarcomatoid-predominant biphasic peritoneal metastases is a rapidly progressing and deeply invasive variant of this disease with survival measured in months. Although cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is a standard of care for epithelioid peritoneal mesothelioma, the sarcomatoid variant is so aggressive, the standard treatment is not recommended. Immunotherapy has recently been utilized for pleural mesothelioma. Partial responses to immunotherapy may be combined with CRS to achieve a favorable outcome in sarcomatoid-predominant peritoneal mesothelioma.

CASE PRESENTATION

A 39-year-old woman developed an expanding abdomen. A 10 cm pelvic mass was removed by hysterectomy. With an initial diagnosis of advanced ovarian cancer, she was treated with cisplatin plus paclitaxel. Disease progression led to a review of her original pathology and a repeat biopsy which showed biphasic peritoneal mesothelioma with sarcomatoid predominance. Treatment with Nivolumab was transiently beneficial. Repeat CT 8 months later showed partial bowel obstruction and necrotic expanding tumor masses that were partially calcified. CRS with HIPEC and normothermic long-term intraperitoneal pemetrexed (NIPEC) plus intravenous cisplatin resulted in a 5-year disease-free survival.

CLINICAL DISCUSSION

The specimens removed at CRS showed marked progression within large masses. Smaller masses resected with CRS showed fibrosis and calcification. The response to Nivolumab was heterogeneous with smaller masses with good blood supply adequately treated but larger masses markedly progressed.

CONCLUSIONS

A combination of partial response to immunotherapy with a complete CRS plus HIPEC and NIPEC can result in a long-term favorable outcome.

Similar Survival Among All Subtypes of Mucinous Appendiceal Adenocarcinoma Except the Intermediate Subtype, Which Shows an Improved Survival

BACKGROUND

Limited success in the management of mucinous appendiceal adenocarcinoma (MACA) has been reported.

METHODS

Cytoreductive surgery with perioperative intraperitoneal chemotherapy was used to treat a cohort of patients with peritoneal dissemination of MACA. The clinical and histopathologic variables were assessed for their impact on overall survival.

RESULTS

The study analyzed 196 patients during a median follow-up period of 8 years. The patients had a median age was 46 years, a median survival of 12 years, and a mean survival of 12.4 years. Preoperative systemic chemotherapy and a high prior surgical score had a negative impact on prognosis. Survival was better for 37 patients (18.9%) with mucinous appendiceal adenocarcinoma-Intermediate (MACA-Int) histology than for 159 patients (81.1%) with MACA grade 1, 2, or 3, or signet ring cells (S) (p = 0.0004). Although MACA-1 and MACA-2 versus MACA-3 and MACA-S had a difference in survival of 63.9 versus 43.2 years at 5 years, with long-term follow-up evaluation, the differences in survival became insignificant (p = 0.5841).

CONCLUSION

The histologic subtype of MACA-Int had a 10-year survival of 81.1%, which was markedly superior to that of MACA-1, -2, -3, or -S (32.7%). With long-term follow-up evaluation, MACA-1, -2, -3, and -S did not differ significantly in survival.