Repeat Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy for Recurrent Mucinous Appendiceal Adenocarcinoma: A Viable Treatment Strategy with Demonstrable Benefit

INTRODUCTION

Many patients with mucinous appendiceal adenocarcinoma experience peritoneal recurrence despite complete cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Prior work has demonstrated that repeat CRS/HIPEC can prolong survival in select patients. We sought to validate these findings using outcomes from a high-volume center.

PATIENTS AND METHODS

Patients with mucinous appendiceal adenocarcinoma who underwent CRS/HIPEC at MD Anderson Cancer Center between 2004 and 2021 were stratified by whether they underwent CRS/HIPEC for recurrent disease or as part of initial treatment. Only patients who underwent complete CRS/HIPEC were included. Initial and recurrent groups were compared.

RESULTS

Of 437 CRS/HIPECs performed for mucinous appendiceal adenocarcinoma, 50 (11.4%) were for recurrent disease. Patients who underwent CRS/HIPEC for recurrent disease were more often treated with an oxaliplatin or cisplatin perfusion (35%/44% recurrent vs. 4%/1% initial, p < 0.001), had a longer operative time (median 629 min recurrent vs. 511 min initial, p = 0.002), and had a lower median length of stay (10 days repeat vs. 13 days initial, p < 0.001). Thirty-day complication and 90-day mortality rates did not differ between groups. Both cohorts enjoyed comparable recurrence free survival (p = 0.82). Compared with patients with recurrence treated with systemic chemotherapy alone, this select cohort of patients undergoing repeat CRS/HIPEC enjoyed better overall survival (p < 0.001).

CONCLUSIONS

In appropriately selected patients with recurrent appendiceal mucinous adenocarcinoma, CRS/HIPEC can provide survival benefit equivalent to primary CRS/HIPEC and that may be superior to that conferred by systemic therapy alone in select patients. These patients should receive care at a high-volume center in the context of a multidisciplinary team.

Efficacy of Systemic Chemotherapy in Patients With Low-grade Mucinous Appendiceal Adenocarcinoma: A Randomized Crossover Trial

Importance

Appendiceal adenocarcinoma is a rare tumor, and given the inherent difficulties in performing prospective trials in such a rare disease, there are currently minimal high-quality data to guide treatment decisions, highlighting the need for more preclinical and clinical investigation for this disease.

Objective

To prospectively evaluate the effectiveness of fluoropyrimidine-based systemic chemotherapy in patients with inoperable low-grade mucinous appendiceal adenocarcinoma.

Design, Setting, and Participants

This open-label randomized crossover trial recruited patients at a single tertiary care comprehensive cancer center from September 2013 to January 2021. The data collection cutoff was May 2022. Enrollment of up to 30 patients was planned. Eligible patients had histological evidence of a metastatic low-grade mucinous appendiceal adenocarcinoma, with radiographic imaging demonstrating the presence of mucinous peritoneal carcinomatosis and were not considered candidates for complete cytoreductive surgery. Key exclusion criteria were concurrent or recent investigational therapy, evidence of bowel obstruction, and use of total parenteral nutrition. Data were analyzed from November 2021 to May 2022.

Interventions

Patients were randomized to either 6 months observation followed by 6 months of chemotherapy, or initial chemotherapy followed by observation.

Main Outcomes and Measures

The primary end point was the percentage difference in tumor growth in treatment and observation groups. Key secondary end points included patient-reported outcomes in the chemotherapy and observation periods, objective response rate, rate of bowel complications, and differences in overall survival (OS).

Results

A total of 24 patients were enrolled, with median (range) age of 63 (38 to 82) years, and equal proportion of men and women (eg, 12 men [50%]); all patients had ECOG performance status of 0 or 1. A total of 11 patients were randomized to receive chemotherapy first, and 13 patients were randomized to receive observation first. Most patients (15 patients [63%]) were treated with either fluorouracil or capecitabine as single agent; 3 patients (13%) received doublet chemotherapy (leucovorin calcium [folinic acid], fluorouracil, and oxaliplatin or folinic acid, fluorouracil, and irinotecan hydrochloride), and bevacizumab was added to cytotoxic chemotherapy for 5 patients (21%). Fifteen patients were available to evaluate the primary end point of difference in tumor growth during treatment and observation periods. Tumor growth while receiving chemotherapy increased 8.4% (95% CI, 1.5% to 15.3%) from baseline but was not significantly different than tumor growth during observation (4.0%; 95% CI, -0.1% to 8.0%; P = .26). Of 18 patients who received any chemotherapy, none had an objective response (14 patients [77.8%] had stable disease; 4 patients [22.2%] had progressive disease). Median (range) OS was 53.2 (8.1 to 95.5) months, and there was no significant difference in OS between the observation-first group (76.0 [8.6 to 95.5] months) and the treatment-first group (53.2 [8.1 to 64.1] months; hazard ratio, 0.64; 95% CI, 0.16-2.55; P = .48). Patient-reported quality-of-life metrics identified that during treatment, patients experienced significantly worse fatigue (mean [SD] score, 18.5 [18.6] vs 28.9 [21.3]; P = .02), peripheral neuropathy (mean [SD] score, 6.67 [12.28] vs 38.89 [34.88]; P = .01), and financial difficulty (mean [SD] score, 8.9 [15.2] vs 28.9 [33.0]; P = .001) compared with during observation.

Conclusions and Relevance

In this prospective randomized crossover trial of systemic chemotherapy in patients with low-grade mucinous appendiceal adenocarcinoma, patients did not derive clinical benefit from fluorouracil-based chemotherapy, given there were no objective responses, no difference in OS when treatment was delayed 6 months, and no difference in the rate of tumor growth while receiving chemotherapy.

Trial Registration

ClinicalTrials.gov Identifier: NCT01946854.

A prospective randomized crossover trial of systemic chemotherapy in patients with low-grade mucinous appendiceal adenocarcinoma

163

Background: Appendiceal adenocarcinoma is both a rare and heterogenous tumor, with marked contrast in the natural history of low-grade and high-grade tumors (5-year OS 68% for low-grade vs. 7% for high-grade). While low-grade appendiceal adenocarcinoma is primarily treated with surgical resection sometimes followed by hyperthermic intraperitoneal chemotherapy (HIPEC), many inoperable candidates are treated with systemic chemotherapy although there is no prospective data supporting this practice. The purpose of our study was to objectively evaluate the effectiveness of systemic chemotherapy in low-grade mucinous appendiceal adenocarcinoma. Methods: A randomized crossover trial of surgically unresectable low-grade (well differentiated) mucinous appendiceal adenocarcinoma was performed with patients randomized to either 6 months observation followed by 6 months of chemotherapy (physician’s choice), or initial chemotherapy followed by observation. In this way each patient would serve as their own control. Enrollment of 30 patients was planned to have complete 6- and 12-month tumor measurements for 24 patients, providing 80% power at 0.05 significance level to detect a 5.0% difference in change in tumor size as measured by peritoneal RECIST in observation vs. treatment periods. Results: The trial closed early due to slow accrual. A total of 24 patients were enrolled. The majority of patients were treated with either 5FU or capecitabine (n = 15, 63%), bevacizumab was added for 3 (13%), and 3 were treated with doublet chemotherapy (FOLFOX/FOLFIRI). 15 patients who completed both treatment and observation periods were available for the primary analysis, the mean difference in tumor size was -4.5% (95% CI: -12.6, 3.7), indicating a slight trend towards faster growth on treatment than observation. This difference was not statistically or clinically significant (8.4% growth on treatment vs. 4.0% observation, p=0.26). Of the 18 patients who received any chemotherapy during the study period, zero achieved an objective response, 14 (77.8%) had stable disease during the entire year of follow up, and 4 (12.2%) had progression on study. Patient reported quality of life metrics identified that fatigue (p=0.02), peripheral neuropathy (p=0.014), and financial difficulty (p=0.0013) were all significantly worse while on treatment. There was not a significant difference in rate of bowel obstruction between the treatment first vs. observation first arms (12.5%, (n=3) vs 8.3%, (n=2)). Conclusions: These data from a prospective, randomized crossover trial indicate that patients with low-grade mucinous appendiceal adenocarcinoma do not derive benefit from 5FU based chemotherapy but do incur toxicity. These data further highlight the unique biology of low-grade appendiceal cancer and demonstrates the need to identify novel systemic therapies for this patient population. Clinical trial information: NCT01946854 .

Stratification of outcomes for mucinous appendiceal adenocarcinoma with peritoneal metastasis by histological grade

AIM

To investigate the importance of a three-tiered histologic grade on outcomes for patients with mucinous appendiceal adenocarcinoma (MAA).

METHODS

Two hundred and sixty-five patients with MAA undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy were identified from a prospective database from 2004 through 2014. All pathology was reviewed by our gastrointestinal subspecialty pathologists and histological grade was classified as well-differentiated, moderately differentiated, and poorly differentiated. Survival analysis was performed using Cox proportional hazards regression.

RESULTS

There were 201 (75.8%) well-, 45 (16.9%) moderately- and 19 (7.2%) poorly-differentiated tumors. Histological grade significantly stratified the 5-year overall survival (OS), 94%, 71% and 30% respectively (P < 0.001) as well as the 5-year disease-free survival (DFS) 66%, 21% and 0%, respectively (P < 0.001). Independent predictors of DFS included tumor grade (HR = 1.78, 95%CI: 1.21-2.63, P = 0.008), lymph node involvement (HR = 0.33, 95%CI: 0.11-0.98, P < 0.02), previous surgical score (HR = 1.31, 95%CI: 1.1-1.65, P = 0.03) and peritoneal carcinomatosis index (PCI) (HR = 1.05, 95%CI: 1.02-1.08, P = 0.002). Independent predictors of OS include tumor grade (HR = 2.79, 95%CI: 1.26-6.21, P = 0.01), PCI (HR = 1.10, 95%CI: 1.03-1.16, P = 0.002), and complete cytoreduction (HR = 0.32, 95%CI: 0.11-0.92, P = 0.03). Tumor grade and PCI were the only independent predictors of both DFS and OS. Furthermore, histological grade and lymphovascular invasion stratified the risk of lymph node metastasis into a low (6%) and high (40%) risk groups.

CONCLUSION

Our data demonstrates that moderately differentiated MAA have a clinical behavior and outcome that is distinct from well- and poorly-differentiated MAA. The three-tier grade classification provides improved prognostic stratification and should be incorporated into patient selection and treatment algorithms.

Intrathoracic Chemoperfusion Decreases Recurrences in Patients with Full-Thickness Diaphragm Involvement with Mucinous Appendiceal Adenocarcinoma

BACKGROUND

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) is the preferred treatment for selected patients with mucinous appendiceal adenocarcinoma. Frequently, the hemidiaphragms are infiltrated with tumor, requiring partial diaphragm resection (DR) in order to obtain complete cytoreduction (CC-0). The clinical significance of diaphragmatic invasion and the optimum management to prevent transmission of disease from abdomen to chest is largely unknown.

METHODS

This was a retrospective review of 78 patients with mucinous appendiceal adenocarcinoma undergoing cytoreduction and partial DR at a single institution between 2010 and 2014.

RESULTS

Partial DR was necessary in 31 (39.7 %) patients in order to obtain CC-0. DR was not associated with increased morbidity or poor survival. Of the 31 patients who had a DR, 26 (83.9 %) were treated with thoracoabdominal chemoperfusion. The remaining five (16.1 %) patients had the diaphragm closed prior to HIPEC. Thoracoabdominal chemoperfusion was not associated with increased 30-day grade III/IV morbidity or respiratory complications. Overall, five (20 %) patients with a DR developed thoracic recurrence. There were two (8 %) thoracic recurrences in the 26 patients treated with thoracic chemoperfusion compared with three (60 %) in the five patients who had their diaphragm closed prior to HIPEC (p = 0.002). In univariate analysis histology, CC-0 and thoracoabdominal chemoperfusion were associated with thoracic disease-free survival; however, none of these were significant on multivariate analysis.

CONCLUSION

DR is not associated with increased morbidity and should be performed, if needed, to obtain a CC-0. Following DR, patients remain at significant risk of developing thoracic recurrence. Thoracoabdominal chemoperfusion reduces this risk without increasing morbidity.

Feeding tube placement during cytoreductive surgery and heated intraperitoneal chemotherapy does not improve postoperative nutrition and is associated with longer length of stay and higher readmission rates

BACKGROUND

Patients with colorectal cancer and peritoneal carcinomatosis (CRC/PC) may benefit from cytoreductive surgery and heated intraperitoneal chemotherapy (CRS/HIPEC). Nutritional support is frequently required for patients after CRS/HIPEC. It remains unclear if placement of feeding access is of benefit in regard to improving postoperative nutrition in this patient population.

MATERIALS AND METHODS

Patients with CRC/PC who underwent complete cytoreduction were evaluated. Preoperative and postoperative nutritional data and discharge outcomes were retrospectively recorded. The presence of a feeding tube and PCI scores were recorded by review of operative notes. Readmission rates were calculated for patients at 30 d and 60 d after discharge from hospital.

RESULTS

Forty-one patients underwent CRS/HIPEC, 25 had feeding tube placement at the time of surgery. Weight loss was common after HIPEC as 38 of 41 patients demonstrated weight loss. The mean weight loss was 7.6%. total parenteral nutrition was required at discharge in four patients (7.9%); three of these patients had feeding access placed. There was no difference in the degree of weight loss between groups (7.1 ± 3.7% no tube versus 7.9 ± 5.8% patients with tube; P = 0.608). The mean decrease in albumin was 12.7% but was not significantly different in patients with feeding access and those without (10.0% versus 14.75%; P = 0.773). Sixty-day readmission rates were higher in patients with feeding tubes (36% compared with 0%, P < 0.01).

CONCLUSIONS

Significant nutritional loss is common after CRS/HIPEC for patients with CRC/PC. Feeding tube placement does not prevent this and appears to be related to higher readmission rates and longer length of stay.

Impact of multidisciplinary therapy on high-grade appendiceal adenocarcinoma (AA)

4134

Background: AA is a rare malignancy ranging from well-differentiated to poorly differentiated carcinoma, including those with signet ring cells. Optimal therapy for low grade peritoneal disease is cytoreductive surgery (CRS) combined with heated intraperitoneal chemotherapy (HIPEC). However, some patients (pts) are suboptimal for CRS/HIPEC, and are considered for systemic chemotherapy (SC) alone, or SC + CRS. In light of our previously reported overall survival (OS) benefits for the role of SC in metastatic AA, here we explore the impact of surgical intervention on OS in these pts. Our aim was to clarify the OS benefit of multidisciplinary therapy (SC + CRS + HIPEC) in those pts with aggressive tumor biology. Methods: A retrospective chart review of AA pts registered in our tumor registry between Jan. 2005 to Dec. 2009 was undertaken to identify patients with AA who received SC. Electronic medical records (EMR) were reviewed for CRS, HIPEC, histology, SC, and OS. The K-M method and Log-Rank test were used for statistical analysis. Results: Of 143 AA pts, 52 (36%) pts were high grade with 33 (23%) having signet ring cells. After a median follow-up of 35M, high grade tumors were noted to have worse OS overall (24M vs 56M, p<.001). When comparing treatment received, and adjusting for tumor biology, those pts with high grade disease again fared worse, and experienced comparatively worse OS. However, those treated with SC + CRS + HIPEC experienced the longest median survival. Conclusions: Pts with peritoneal disease from high grade AA who completed SC with CRS + HIPEC experienced prolonged OS compared to those treated by SC +/- CRS. Our data suggest that SC + palliative CRS offers minimal benefit for high grade disease. Selection bias influences these results heavily; as those who do well proceed to complete all components of therapy. A treatment plan that includes SC + CRS + HIPEC can result in durable survival, and is a strategy that warrants further study emphasizing the importance of multidisciplinary management. [Table: see text]

CT imaging interval after complete cytoreductive surgery/hyperthermic intraperitoneal chemotherapy (HIPEC) for well-differentiated adenocarcinoma of the appendix (WDAA)

434

Background: WDAA with peritoneal dissemination (PD) is a rare disease with a prognosis related to the ability to perform adequate cytoreductive surgery (CRS) with cytoreductive scores of 0 or 1 (CC0 or CC1) followed by HIPEC. Diagnostic imaging is an important aspect of post-operative surveillance. Often, surveillance imaging follows metastatic colon cancer guidelines with frequent CT scans performed during the first 5 years after resection (every 3 months for 2 years, then every 6 months). Minimal evidence-based data exists to direct recommendations regarding optimal imaging intervals in patients with WDAA.

Methods: All patients with a pathologic diagnosis of WDAA with PD who were evaluated at a single institution between August 1993 and January 2010 were retrospectively reviewed to identify patients who underwent a CC0 CRS and HIPEC. Parameters evaluated included demographics, time to recurrence and time to intervention after recurrence. Disease free survival was calculated using the Kaplan-Meier method.

Results: 688 patients were evaluated during the study period. 67 patients (9.7%) had WDAA and underwent CC0 CRS/HIPEC. The mean age at diagnosis was 54.8 years. Twenty-two (32%) were male. Mean follow-up was 50.4 months. Disease free survival of the entire cohort at 10 yrs was 72 %. Eleven patients (16 %) experienced a recurrence. Median time to recurrence was 18.2 months. After recurrence, mean time to intervention was 6 months. In those patients that recurred, only 3 patients underwent intervention within 24 months of the index CRS/HIPEC (4% of overall cohort). Recurrence after 36 months occurred in only one patient (1.5% of cohort).

Conclusions: Patients with WDAA/PD who undergo CC0 CRS/HIPEC have an overall very favorable prognosis and low risk of recurrence. Surveillance imaging, as often done for colorectal cancer, every 3-4 months is inappropriate. For this group of patients, follow-up CT scans every 6 months for 2 years, and then annually is recommended.