Celecoxib and Myrtol: A Novel Therapy for Recurrent Appendiceal Mucinous Neoplasms With Extensive Peritoneal Dissemination.

BACKGROUND: Unresectable appendiceal mucinous neoplasms (AMNs) with extensive peritoneal dissemination cause significant morbidity and have limited treatment options. We evaluated a novel combination of Celecoxib and Myrtol in treating such AMNs. METHODS: Patients with recurrent AMNs with extensive peritoneal disease treated with a daily regimen of 200 mg Celecoxib and 1200 mg Myrtol Standardized were included. Progression-free survival (PFS) and overall survival (OS) were calculated, and carcinoembryonic antigen (CEA) trends were compared pretreatment and post-treatment in terms of percentage change. RESULTS: Thirteen patients with extensive, recurrent disease (median peritoneal carcinomatosis index of 36) were included between 2017 and 2020. The median age was 63 years (interquartile range: 55 to 67) and 7 (54%) were male. A total of 85% had undergone prior cytoreductive surgery while 15% underwent cytoreductive surgery >2 times. 54% had received multiple cycles of systemic chemotherapy before starting Celecoxib-Myrtol. After a median follow-up of 8 months, median PFS and OS were 16 months (interquartile range: 5 to 17) and 27 months, respectively. Nine (69.2%) showed improvement in CEA values 3 months after treatment compared with 3-month pretreatment CEA trends. None had adverse events attributable to Celecoxib-Myrtol. CONCLUSIONS: Our feasibility study suggests that a regimen of Celecoxib-Myrtol is well tolerated and may prolong PFS and OS in patients with recurrent AMNs with peritoneal spread.

Indications and outcomes for repeat cytoreductive surgery and heated intra-peritoneal chemotherapy in peritoneal surface malignancy.

INTRODUCTION: Cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) is offered in specialist centres as a treatment for peritoneal surface tumours. Despite its demonstrated efficacy, intra-abdominal recurrence occurs in 31-57% of patients. The aim of this study is to review the early and long-term outcomes in patients who undergo repeat CRS/HIPEC. MATERIALS AND METHODS: A retrospective review of a prospectively maintained database of patients who had undergone repeat CRS/HIPEC for appendiceal neoplasms and colorectal peritoneal metastases (CRPM) from 2003 to 2019 was performed at a single specialist centre. Data pertaining to both short term outcomes and survival were evaluated. RESULTS: Of 1259 patients who had undergone CRS/HIPEC, 84(6.7%) underwent repeat surgery: 45(53.6%) had pseudomyxoma peritonei (PMP) secondary to low grade appendiceal mucinous neoplasms (LAMN), 21(25.0%) had appendix carcinoma and 18(21.4%) had CRPM. Demographics, intra-operative findings and short-term outcomes were comparable across tumour types and between procedures. Median (95% CI) interval between procedures was 22.7(18.9-26.6) months and was comparable between tumour types. Median (95%CI) overall survival was not reached for the cohort overall or for those with PMP, but was 61.0(32.6-89.4) months for those with appendix cancer and 76.9(47.4-106.4) months for CRPM (p=<0.001). Survival was favourable in the PMP group (HR [95%CI] 0.044 [0.008-0.262]; p = 0.000) and unfavourable in the CC2-3 at index CRS procedure group (HR [95%CI] 25.612 [2.703-242.703]; p = 0.005). CONCLUSION: Our findings demonstrate that repeat cytoredutive surgery with HIPEC can result in favourable survival, especially for patients with PMP when complete cytoreduction is achieved at index operation. We recommend that detailed patient assessment is performed through an expert multidisciplinary team meeting (MDT).

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) for colorectal and appendiceal peritoneal metastases - The Hong Kong experience and literature review.

INTRODUCTION: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is increasingly used to treat peritoneal metastases from appendiceal or colorectal origin. We evaluate our institution's experience and survival outcomes with this procedure, and its efficacy in symptom relief. METHODS: This is a single-centre retrospective observational study on patients with peritoneal metastases (PM) from appendiceal neoplasm or colorectal cancer who underwent CRS/HIPEC in Queen Mary Hospital. Our primary endpoints were overall survival (OS) and morbidity and mortality of this procedure; secondary endpoints included disease-free survival (DFS) and symptom-free survival. RESULTS: Between 2006 and 2018, thirty CRS/HIPEC procedures were performed for 28 patients - 17 (60.7%) had appendiceal PM while 11 (39.9%) had colorectal PM. The median peritoneal cancer index was 20; complete cytoreduction was achieved in 83.3% patients. High-grade morbidity occurred in 13.3% cases. There was no 30-day mortality. Two-year OS were 71.6% and 50% for low-grade appendiceal PM and colorectal PM patients (p = 0.20). Complete cytoreduction improved OS (2-year OS 75.4% vs 20%, p = 0.04). Median DFS was 11.8 months. Median symptom-free duration was 36.8 months; patients with complete cytoreduction were more likely to remain asymptomatic (82.9% at 1 year, vs 60% in incomplete cytoreduction group, p < 0.01). 91.7% low-grade appendiceal PM patients and 58.4% colorectal PM patients remained asymptomatic at post-operative one year (p = 0.31). CONCLUSION: CRS/HIPEC is beneficial to appendiceal PM and selected colorectal PM patients - improving survival and offering prolonged symptom relief, with reasonable morbidity and mortality. Complete cytoreduction is key to realising this benefit.

Outcomes of neoadjuvant chemotherapy before CRS-HIPEC for patients with appendiceal cancer.

BACKGROUND: Cytoreductive surgery (CRS) with or without hyperthermic intraperitoneal chemotherapy (HIPEC) is indicated for patients with peritoneal dissemination of appendiceal cancer. The role of neoadjuvant chemotherapy (NAC) before CRS-HIPEC remains controversial. METHODS: A retrospective review of adult patients who underwent CRS ± HIPEC for metastatic appendiceal cancer between 2000-2017 was performed. Patients who received NAC followed by surgery were compared with those who underwent surgery first (SF) with and without 1:1 propensity score matching (PSM). RESULTS: Among 803 patients with appendiceal cancer who underwent CRS ± HIPEC, 225 (28%) received NAC, and 578 (72%) underwent SF. After PSM (n = 186), median overall survival (OS) did not differ (NAC: 40 vs SF: 56 months; P = .210) but recurrence-free survival (RFS) was worse among patients who received NAC (14 vs 22 months; P = .007). NAC was independently associated with worse OS (hazards ratio [HR], 1.81; 95% confidence interval [CI], 1.03-3.18) and RFS (HR, 1.93; 95% CI, 1.25-2.99). CONCLUSION: In this multi-institutional retrospective analysis of patients with peritoneal dissemination from appendiceal cancer, the use of NAC before CRS-HIPEC was associated with worse OS and RFS even after PSM and multivariable regression. Immediate surgery should be considered for patients with disease amenable to complete cytoreduction.

Management and prognostic prediction of appendiceal mucinous adenocarcinoma with peritoneal metastasis: a single center study in China.

BACKGROUND: To investigate the clinical and pathological characteristics of appendiceal mucinous adenocarcinoma with peritoneal metastasis and analyze the prognostic factors. METHODS: A retrospective analyses of clinicopathological features of 50 patients with appendiceal mucinous adenocarcinoma with peritoneal metastasis from January, 2013 to December, 2017 in Aerospace Central Hospital, Beijing, China. Survival data calculation and comparison were respectively performed with the Kaplan-Meier method and the log-rank test. The Cox proportional hazards regression method was used for multivariate survival analyses. RESULTS: Cytoreduction for appendiceal mucinous adenocarcinoma was conducted on 50 patients (24 males and 26 females), with a median age of 52.5 years at the time of surgery (range 31-71 years). The median overall survival (OS) time was 24 months, with 2-,3- and 5-year survival rates of 53, 24 and 8%, respectively. At the last follow-up in December 2018, 13 patients were still alive. Multivariate analysis revealed that patients who had low Ki-67 expression (less than 50%) and CCR (completeness of cytoreduction) 0/1/2 score had significantly better OS rate than their respective counterparts. CONCLUSIONS: Ki-67 expression statue and CCR score could be employed as the prognosis prediction in patients with appendiceal mucinous adenocarcinoma.

Evaluation of repeat cytoreductive surgery and heated intraperitoneal chemotherapy for patients with recurrent peritoneal carcinomatosis from appendiceal and colorectal cancers: a multicentre Canadian study

Background: Peritoneal recurrences after cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) for appendiceal and colorectal cancers are frequent. This study aimed to evaluate the safety, technical feasibility and perioperative and long-term outcomes of repeat CRS/HIPEC in patients with recurrent peritoneal carcinomatosis of colorectal and appendiceal origin. Methods: Data were collected from patients treated from 2000 to 2016 for recurrent peritoneal carcinomatosis from appendiceal or colorectal cancer with CRS/HIPEC at 2 specialist centres. Data on demographics, procedure details, morbidity and survival were recorded. Analyses compared the iterations of CRS/HIPEC to assess the safety and effectiveness of repeat surgery. Results: Of all patients who underwent CRS/HIPEC in the 2 centres, 37 patients underwent a repeat procedure. Operative time was similar for the first and second surgeries (412.1 v. 412.5 min, p = 0.74) but patients had a significantly lower peritoneal carcinoma index score with the second surgery (21.8 in the first iteration v. 9.53 in the second iteration, p < 0.001) and significantly less blood loss (1762 mL in the first iteration v. 790 mL in the second iteration, p = 0.001). There was a nonsignificant decrease in grade III­IV complications and there was no 30-day mortality associated with repeat procedures. For patients with colorectal cancer, median disease-free survival was 9.6 months and median overall survival was 40 months. For patients with appendiceal cancer, median disease-free survival was 15 months and overall survival was 64.4 months. Conclusion: Repeat CRS/HIPEC procedures for recurrent appendiceal and colorectal peritoneal carcinomatosis are safe in well-selected patients, without increased morbidity or mortality, and they are associated with significant long-term survival, particularly for patients with appendiceal cancers. These results support the use of repeat CRS/HIPEC in these patients.

Contexte: Les récurrences péritonéales après une chirurgie cytoréductrice (CCR) et une chimiothérapie hyperthermique intrapéritonéale (CHIP) pour les cancers de l'appendice et colorectaux sont fréquentes. Cette étude visait à évaluer l'innocuité, la faisabilité technique et les résultats périopératoires et à long terme d'une reprise de CCR/CHIP chez les patients qui présentent une récurrence de carcinomatose péritonéale ayant son origine au niveau colorectal ou de l'appendice. Méthodes: Des données ont été recueillies sur des patients traités entre 2000 et 2016 pour une récurrence de carcinomatose péritonéale ayant son origine au niveau colorectal ou de l'appendice par CCR/CHIP dans 2 centres spécialisés. On a tenu compte des données démographiques, des détails des interventions, ainsi que de la morbidité et de la survie. Des analyses ont permis de comparer les premières et deuxièmes CCR/CHIP pour évaluer l'innocuité et l'efficacité des chirurgies répétées. Résultats: De tous les patients soumis à des CCR/CHIP dans les 2 centres, 37 ont subi l'intervention de nouveau. Le temps opératoire a été similaire pour les premières et les deuxièmes chirurgies (412,1 c. 412,5 min, p = 0,74), mais les patients présentaient un score de carcinomatose péritonéale beaucoup plus bas lors de la deuxième chirurgie (21,8 pour la première intervention c. 9,53 pour la seconde, p < 0,001) et des pertes sanguines significativement moindres (1762 mL pour la première intervention c. 790 mL pour la seconde, p = 0,001). On a noté une diminution non significative des complications de grades III­IV et on n'a déploré aucune mortalité à 30 jours en lien avec la reprise de l'intervention. Pour les patients atteints d'un cancer colorectal, la survie médiane sans maladie a été de 9,6 mois et la survie médiane globale a été de 40 mois. Pour les patients atteints d'un cancer de l'appendice, la survie médiane sans maladie a été de 15 mois et la survie médiane globale a été de 64,4 mois. Conclusion: La reprise des CCR/CHIP pour les récurrences de carcinomatose péritonéale ayant leur origine au niveau colorectal ou de l'appendice est sécuritaire chez les patients soigneusement sélectionnés, sans accroissement de la morbidité ou de la mortalité, et elles sont associées à une survie à long terme significative, particulièrement chez les patients ayant un cancer de l'appendice. Ces résultats appuient la reprise des CCR/CHIP chez ces patients.

Outcomes in Peritoneal Carcinomatosis from Appendiceal Goblet Cell Carcinoma Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS/HIPEC).

BACKGROUND: Appendiceal goblet cell adenocarcinoma (GCA) is often misclassified and mistreated due to mixed histologic features. In general, cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is standard of care for peritoneal carcinomatosis (PC) from mucinous appendiceal tumors; however, in PC from GCA, data are limited and the role of CRS/HIPEC is controversial. We report outcomes in PC from appendiceal GCA treated with CRS/HIPEC. PATIENTS AND METHODS: A prospective institutional database of 391 CRS/HIPEC patients with appendiceal carcinomatosis from 1998 to 2018 was reviewed. Twenty-seven patients with GCA were identified. Perioperative variables were described. Survival was estimated using the Kaplan-Meier method. RESULTS: GCA occurred in 7% (27/391) of appendiceal CRS/HIPEC patients. Seven (26%) cases were aborted. Two patients underwent a second CRS/HIPEC for peritoneal recurrence. Median age at diagnosis was 53 years (range 39-72 years), and 12 (60%) were female. All underwent previous surgery. Seven (35%) had prior chemotherapy and received a median of 5 cycles (range 3-8). Median PCI was 6 (range 1-39). Complete cytoreduction was achieved in 95% (19/20). Grade III complications occurred in three (15%) patients, and no perioperative deaths occurred. Median follow-up was 97 months. Overall survival at 1, 3 and 5 years was 100%, 74% and 67%, respectively. Progression-free survival at 1, 3, and 5 years was 94%, 67% and 59%, respectively. CONCLUSION: CRS/HIPEC should be considered as the main treatment option for patients with PC from appendiceal GCA. When performed at a CRS/HIPEC specialty center, 5-year OS of 67% can be achieved.

Preoperative Risk Score for Predicting Incomplete Cytoreduction: A 12-Institution Study from the US HIPEC Collaborative.

BACKGROUND: For patients with peritoneal carcinomatosis undergoing cytoreductive surgery with heated intraperitoneal chemotherapy (CRS/HIPEC), incomplete cytoreduction (CCR2/3) confers morbidity without survival benefit. The aim of this study is to identify preoperative factors which predict CCR2/3. METHODS: All patients who underwent curative-intent CRS/HIPEC of low/high-grade appendiceal, colorectal, or peritoneal mesothelioma cancers in the 12-institution US HIPEC Collaborative from 2000 to 2017 were included (n = 2027). The primary aim is to create an incomplete-cytoreduction risk score (ICRS) to predict CCR2/3 CRS utilizing preoperative data. ICRS was created from a randomly selected cohort of 50% of patients (derivation cohort) and verified on the remaining patients (validation cohort). RESULTS: Within our derivation cohort (n = 998), histology was low-grade appendiceal neoplasms in 30%, high-grade appendiceal tumor in 41%, colorectal tumor in 22%, and peritoneal mesothelioma in 8%. CCR0/1 was achieved in 816 patients and CCR 2/3 in 116 patients. On multivariable analysis, preoperative factors associated with incomplete cytoreduction were male gender [odds ratio (OR) 3.4, p = 0.007], presence of ascites (OR 2.8, p = 0.028), cancer antigen (CA)-125 ≥ 40 U/mL (OR 3.4, p = 0.012), and carcinoembryonic antigen (CEA) ≥ 4.2 ng/mL (OR 3.2, p = 0.029). Each preoperative factor was assigned a score of 0 or 1 to form an ICRS from 0 to 4. Scores were grouped as zero (0), low (1-2), or high (3-4). Incidence of CCR2/3 progressively increased by risk group from 1.6% in zero to 13% in low and 39% in high. When ICRS was applied to the validation cohort (n = 1029), this relationship was maintained. CONCLUSION: The incomplete cytoreduction risk score incorporates preoperative factors to accurately stratify the risk of CCR2/3 resection in CRS/HIPEC. This score should not be used in isolation, however, to exclude patients from surgery.

Outcomes After Adjuvant Hyperthermic Intraperitoneal Chemotherapy for High-Risk Primary Appendiceal Neoplasms After Complete Resection.

INTRODUCTION: Appendiceal neoplasms are uncommon tumors. Optimal treatment for patients with perforation or high-grade pathology after initial resection is unknown. This study evaluated patients with increased risk for peritoneal dissemination after primary resection, but no evidence of peritoneal disease, who underwent adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC). METHODS: This multi-institutional cohort study evaluated 56 patients with high-risk (HR) appendiceal neoplasms with a peritoneal carcinomatosis index of 0 who underwent HIPEC. The patients were divided into two groups: perforated low-grade appendiceal (LGA) carcinoma and HR neoplasms, which included perforated high-grade appendiceal carcinoma, positive margins after initial resection, minimal macroscopic peritoneal disease that was previously resected or completely responded to systemic chemotherapy prior to HIPEC, goblet cell carcinoma, and adenocarcinoma with signet ring cell features. Overall survival (OS) and recurrence-free survival (RFS) were estimated by Kaplan-Meier analysis. RESULTS: Thirty-eight percent of patients had perforated LGA and 68% had HR features. Five-year OS probability was 82.1% for the entire cohort, and 100% and 70.1% for patients with perforated LGA and HR features, respectively (p = 0.024). Five-year RFS probability was 79.3% for the entire cohort, and 90.0% and 72.4% for patients with perforated LGA and HR features, respectively (p = 0.025). Eight patients recurred after HIPEC and their OS was significantly worse (p < 0.001). CONCLUSION: While adjuvant HIPEC is both safe and feasible, there appears to be little benefit over close surveillance when outcomes are compared with historical and prospective studies, especially for perforated LGA carcinoma.

Surveillance of Low-Grade Appendiceal Mucinous Neoplasms With Peritoneal Metastases After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: Are 5 Years Enough? A Multisite Experience.

BACKGROUND: Low-grade appendiceal mucinous neoplasms (LAMNs) are tumors that often present with widespread mucin in the peritoneal cavity (pseudomyxoma peritonei [PMP]). Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are effective treatment, but no published recommendations exist regarding surveillance. METHODS: Data from prospective databases of patients who underwent CRS-HIPEC from 2001 to 2017 at two high-volume institutions were retrospectively analyzed. Patients who underwent complete CRS-HIPEC for PMP secondary to LAMN were included in the analysis. Pathologic examination confirmed the diagnosis of LAMN. Cases of mucinous adenocarcinomas and neuroendocrine tumors (goblet cell carcinoids) were excluded. RESULTS: The study enrolled 156 patients. The median peritoneal cancer index (PCI) was 18 (interquartile range IQR1-3, 12-23), and 125 patients (80.1%) had a CC0 cytoreduction. According to American Joint Committee on Cancer (AJCC) grading, 152 patients (97.4%) presented with acellular mucin or G1 implants, 2 patients (1.3%) presented with G2 disease, and 2 patients (1.3%) presented with G3 disease. During the follow-up period (median, 45 months; IQR1-3 23-76 months), 23 patients (14.7%) experienced recurrence. All the recurrences were peritoneal and occurred within 5 years. The 1-, 3-, and 5-year disease-free survival (DFS) rates were respectively 95.5%, 83.4%, and 78.3%. Univariate Cox regression analysis showed that higher PCI scores (p < 0.001), a CC1 cytoreduction (p = 0.005), and higher preoperative levels of carcinoembryonic antigen (CEA) (p = 0.012) and CA-125 (p = 0.032) correlated with a shorter DFS. Only higher PCI scores independently predicted earlier recurrences (p < 0.001). CONCLUSION: Most patients had recurrence within 3 years after CRS-HIPEC, and none after 5 years. High PCI was the only independently significant variable. The study findings support intensive surveillance (every 3-6 months) with tumor markers and imaging methods during the first 3 years, and annual surveillance thereafter, with follow-up assessment after 5 years yielding limited benefit.

Prognostic Impact of BRAF and KRAS Mutation in Patients with Colorectal and Appendiceal Peritoneal Metastases Scheduled for CRS and HIPEC.

BACKGROUND: KRAS and BRAF mutations are prognostic and predictive tools in metastatic colorectal cancer, but little is known about their prognostic value in patients scheduled for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Therefore, we analyzed the prognostic impact of KRAS and BRAF mutations in patients with peritoneal metastases scheduled for CRS and HIPEC. PATIENTS AND METHODS: In a consecutive series of 399 patients scheduled for CRS and HIPEC between 2009 and 2017, 111 subjects with peritoneal metastases from primaries of the appendix, colon, or rectum were analyzed for KRAS mutation and 92 for BRAF mutation. RESULTS: Mutation in KRAS was present in 51/111 (46%), and mutated BRAF was found in 10/92 (11%). There was no difference in overall survival between KRAS mutation tumors and KRAS wild type, whereas BRAF mutation was associated with short survival. No subject with BRAF mutation survived 2 years. On multivariate analysis, completeness of cytoreduction score (CCS, p = 0.000001), presence of signet cell differentiation (p = 0.000001), and BRAF mutation (p = 0.0021) were linked with poor prognosis. CONCLUSIONS: BRAF mutation is a marker of poor prognosis in patients with appendiceal and colorectal peritoneal metastases scheduled for CRS and HIPEC, whereas survival outcome in subjects with mutated KRAS does not differ from wild-type KRAS. This finding suggests that those with BRAF mutation should be considered for alternative treatment options.

Optimal Surveillance Frequency After CRS/HIPEC for Appendiceal and Colorectal Neoplasms: A Multi-institutional Analysis of the US HIPEC Collaborative.

BACKGROUND: No guidelines exist for surveillance following cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) for appendiceal and colorectal cancer. The primary objective was to define the optimal surveillance frequency after CRS/HIPEC. METHODS: The U.S. HIPEC Collaborative database (2000-2017) was reviewed for patients who underwent a CCR0/1 CRS/HIPEC for appendiceal or colorectal cancer. Radiologic surveillance frequency was divided into two categories: low-frequency surveillance (LFS) at q6-12mos or high-frequency surveillance (HFS) at q2-4mos. Primary outcome was overall survival (OS). RESULTS: Among 975 patients, the median age was 55 year, 41% were male: 31% had non-invasive appendiceal (n = 301), 45% invasive appendiceal (n = 435), and 24% colorectal cancer (CRC; n = 239). With a median follow-up time of 25 mos, the median time to recurrence was 12 mos. Despite less surveillance, LFS patients had no decrease in median OS (non-invasive appendiceal: 106 vs. 65 mos, p < 0.01; invasive appendiceal: 120 vs. 73 mos, p = 0.02; colorectal cancer [CRC]: 35 vs. 30 mos, p = 0.8). LFS patients had lower median PCI scores compared with HFS (non-invasive appendiceal: 10 vs. 19; invasive appendiceal: 10 vs. 14; CRC: 8 vs. 11; all p < 0.01). However, on multivariable analysis, accounting for PCI score, LFS was still not associated with decreased OS for any histologic type (non-invasive appendiceal: hazard ratio [HR]: 0.28, p = 0.1; invasive appendiceal: HR: 0.73, p = 0.42; CRC: HR: 1.14, p = 0.59). When estimating annual incident cases of CRS/HIPEC at 375 for non-invasive appendiceal, 375 invasive appendiceal and 4410 colorectal, LFS compared with HFS for the initial two post-operative years would potentially save $13-19 M/year to the U.S. healthcare system. CONCLUSIONS: Low-frequency surveillance after CRS/HIPEC for appendiceal or colorectal cancer is not associated with decreased survival, and when considering decreased costs, may optimize resource utilization.

Improved Survival with Experience: A 10-Year Learning Curve in Hyperthermic Intraperitoneal Chemotherapy and Cytoreductive Surgery.

BACKGROUND: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is an aggressive locoregional treatment for peritoneal carcinomatosis (PC). Studies demonstrate improved perioperative and oncologic outcomes at high-volume centers. METHODS: This study retrospectively analyzed all patients with PC from various malignancies who underwent attempted CRS/HIPEC at the authors' institution from 2007 to 2017. Clinicopathologic, perioperative, and oncologic outcomes of early (2007-2012) and late (2012-2017) experience were compared, and multivariate analyses for factors predictive of perioperative and oncologic outcomes were performed. RESULTS: The study enrolled 388 patients (157 early and 231 late). The late experience contained more appendiceal low-grade mucinous neoplasms (LGMNs; 21% vs 9%) and had a lower Peritoneal Cancer Index (PCI; 10 vs 16). Moreover, achieving a similar rate of CC-0/1 required fewer organ resections, involved shorter operations (298 vs 347 min), and had lower estimated blood loss (EBL) (400 vs 200 ml) (p < 0.05). More procedures were aborted (20% vs 3%; p < 0.01). The late experience had fewer ICU admissions (13% vs. 55%) and a lower perioperative mortality rate (0% vs 3%) (p < 0.05). In the multivariate analyses, PCI and number of organ resections were independent predictors of multiple perioperative outcomes [EBL, operating room time, intensive care unit (ICU) admission, ICU length of stay (LOS), overall LOS]. Survival was significantly longer in the late cohort (median overall survival: NR vs 31 months; progression-free survival: 22 vs 11 months; p < 0.01), even after control for tumor histology. CONCLUSIONS: At the authors' high-volume center, with increased surgeon and institutional experience over time, perioperative and oncologic outcomes have improved significantly for patients undergoing CRS/HIPEC for PC.

Short- and Long-Term Outcomes of Patients Requiring Gastrectomy During Cytoreductive Surgery and Intraperitoneal Chemotherapy for Lower-Gastrointestinal Malignancies: A Propensity Score-Matched Analysis.

OBJECTIVES: This study was designed to assess the short- and long-term outcomes of gastric resection in cytoreductive surgery (CRS) and intraperitoneal chemotherapy (IPC) for lower gastrointestinal (GI) malignancies. METHODS: Patients with adenocarcinoma and appendiceal mucinous neoplasms were included. Redo and incomplete cytoreductions were excluded. A total of 756 patients were identified. Of these, 65 underwent gastric resection, 11 underwent wedge, 43 distal, and 11 subtotal and total gastrectomy. Preoperative differences were assessed for and addressed with matching. Perioperative outcomes, overall survival (OS), and risk-free survival (RFS) were assessed in two analyses: first all gastric resections were included and the second excluded wedge resections. Subgroup analysis according to diagnosis subtype was conducted. RESULTS: Demographic analysis revealed that markers of tumor aggression and poor nutrition were prevalent in the gastrectomy group. The matched analysis for gastric resections revealed higher rates of reoperation (38% vs. 22%, p = 0.028). After excluding wedge resections, increased rates of reoperation (40% vs. 22%, 0.019), grade 3/4 morbidity (76% vs. 59%, p = 0.036), and hospital stay (34 vs. 27 days, p = 0.012) were observed. For the unmatched cohort, OS (103 vs. 69 months, p = 0.501) and RFS (17 vs. 18 months, p = 0.181) for patients with CC = 0 were insignificantly different. In comparison for CC > 0, OS (31 vs. 83 months, p < 0.001) and RFS (9 vs. 20 months, p < 0.001) were significantly reduced in gastric resection. For the matched cohort, after excluding wedges, gastrectomy did not significantly decrease OS. However, RFS was decreased (11 vs. 20 months, p = 0.016). CONCLUSIONS: Despite high postoperative morbidity, when complete cytoreduction is achieved, the need for gastric resection is not associated with inferior long-term outcomes.

Systemic chemotherapy before cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) in patients with high-grade mucinous carcinoma peritonei of appendiceal origin.

BACKGROUND: The role of systemic chemotherapy (SC) before cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) in appendiceal high-grade mucinous carcinoma peritonei (HGMCP) is controversial. We analyzed the effect of SC prior to CRS/HIPEC in HGMCP. METHODS: A prospective database of CRS/HIPEC procedures for HGMCP without signet ring cells and with signet ring cells (HGMCP-S) from 1998 to 2017 was reviewed. Exclusion criteria was prior surgery >5 regions or >2 regimens of prior SC. Perioperative variables were analyzed. RESULTS: There were 140 HGMCP/HGMCP-S identified: 64 with prior SC (preSC) and 76 without (noSC). Groups were balanced for lymph node status, complete cytoreduction rate, disease burden, complications, and postoperative SC. PreSC had more HGMCP-S, moderately/poorly differentiated histology, and longer time-to-surgery (median: 6 vs 2 months, p < 0.001). Median overall survival (mOS) was 40 vs 86 and median progression-free survival (mPFS) was 19 vs 43 months for preSC vs noSC, respectively (p = 0.006 and p = 0.007). In HGMCP-S subanalysis, mOS was 25 vs 39 and mPFS 16 vs 29 months for preSC vs noSC, respectively (p = 0.188 and p = 0.063). In moderately/poorly differentiated histology subanalysis, mOS was 38 vs 56 and mPFS 18 vs 29 months in preSC vs noSC, respectively (p = 0.199 and 0.082). Prior SC was not linked to improved OS or PFS in non-signet ring HGMCP or well-differentiated histology subanalysis. CONCLUSION: Prior SC was not associated with less disease burden, better cytoreduction rates, or improved clinical outcomes in HGMCP, regardless of histopathologic subtype. Traditional SC agents may not be effective in HGMCP in the neoadjuvant setting.

Selection and Characteristics of Patients with Peritoneal Dissemination from Appendiceal Cancer with Exceptional/Poor Survival After CRS/HIPEC.

BACKGROUND: Survival in peritoneal dissemination from appendiceal cancer after complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) varies within each histopathologic subtype. Analyzing patients with unique responses may uncover the mechanisms behind their extreme outcomes. We proposed a method to identify retrospectively and to characterize patients who responded exceptionally well or very poorly within each histopathologic subtype. METHODS: Retrospective review of patients with low-grade mucinous carcinoma peritonei (LGMCP), high-grade MCP (HGMCP), and HGMCP with signet ring cells (HGMCP-S) with complete CRS/HIPEC (CC-0/1) was performed. Patients were divided by recurrence status. Median follow-up was calculated for each. Exceptional responders (ExR) were defined as alive without recurrence after median follow-up of the nonrecurrent group. Poor responders (PoR) were defined as disease recurrence before median follow-up of the recurrent group. Perioperative characteristics were analyzed. RESULTS: LGMCP, HGMCP, and HGMCP-S had 48 (41%), 19 (23%), and 7 (14%) ExR and 11 (10%), 20 (24%), and 20 (39%) PoR, respectively. All ExR had lower median PCI (26 vs. 36 [p = 0.004]; 13 vs. 33.5 [p < 0.001]; 3 vs. 29.5 [p = 0.001]). Fewer LGMCP and HGMCP ExR had abnormal tumor markers (36% vs. 90% [p = 0.003]; 22% vs. 74% [p = 0.003]). More HGMCP and HGMCP-S ExR had CC-0 (vs. CC-1) cytoreductions (84% vs. 50%, p = 0.041; 100% vs. 40%, p = 0.008). CONCLUSIONS: Stratifying patients by recurrence status and follow-up time successfully selects ExR and PoR within each histopathologic subtype. Perioperative characteristics of ExR versus PoR differ across histopathologic subtypes, except for disease burden. Genetic analysis may further elucidate differences and aid in the development of novel targeted therapies.

Discrimination of low- and high-grade appendiceal mucinous neoplasms by targeted sequencing of cancer-related variants.

DNA was obtained from matching micro-dissected, primary tumor cells, paired metastases, and peripheral blood mononuclear cells (germline) from patients with appendiceal mucinous neoplasms. We compared specimens from patient cohorts comprising low-grade adenomucinous neoplasm versus high-grade mucinous adenocarcinoma using a targeted, amplicon sequencing panel of 409 cancer related genes (Ion Torrent Comprehensive Cancer Panel, Thermo-Fisher, Waltham, MA). Copy number variants, single nucleotide variants and small insertions/deletions were identified using a multiplex algorithm pipeline (GATK, VarScan2, MuTect2, SIFT, SIFT-INDEL, PolyPhen-2, Provean). There were significantly more damaging variants in high-grade versus low-grade tumor cohorts. Both cohorts contained damaging, heterozygous germline variants (catenin ß1; notch receptor 1 and 4) in pathways associated with cell-lineage specification (WNT, NOTCH). Damaging, somatic KRAS proto-oncogene, GTPase mutations were present in both cohorts, while somatic GNAS complex locus mutations were confined to low-grade neoplasms. Variants predominantly affected transcription factors, kinases, and stem cell signaling molecules in canonical pathways including epithelial to mesenchymal transition, stem cell pluripotency, p53, PTEN, and NF-қB signaling pathways. High-grade tumors demonstrated MYC proto-oncogene, bHLH transcription factor (MYC) and death domain associated protein (DAXX) amplification and damaging somatic variants in tumor protein p53 (TP53), likely to amplify an aggressive phenotype. Damaging APC, WNT signaling pathway regulator (APC) deletions were identified in metastatic tissue of both cohorts suggesting a role in invasive disease. Our data suggest that germline dysregulation of WNT and/or NOTCH pathways predisposes patients toward a secretory cell phenotype (i.e., goblet-like cells) upon acquisition of somatic KRAS mutations. Additional somatically acquired variants activating oncogenes MYC and DAXX and inhibiting the critical tumor suppressor, tumor protein TP53, were consistent with manifestation of a high-grade phenotype. These additional changes within the epithelial to mesenchymal transition signaling network (WNT, NOTCH, RAS/ERK/PI3K, PTEN, NF-қB), produce aggressive high-grade tumor characteristics by actively driving cells towards dedifferentiation, proliferation, and migration.

Long term survival analysis after hyperthermic intraperitoneal chemotherapy with oxaliplatin as a treatment for appendiceal peritoneal carcinomatosis.

BACKGROUND AND OBJECTIVES: Complete cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) have been proven to lengthen survival in appendiceal peritoneal carcinomatosis (PC-A). The aim of this study was to analyze survival results of this therapy in our institution over the last 10 years. METHODS: Data was retrospectively reviewed and analyzed. Treatment consisted of CRS plus HIPEC with oxaliplatin. Ronnett's histologic classification was used (peritoneal mucinous carcinomatosis (PMCA), PMCA with intermediate features (PMCA-I) and disseminated peritoneal adenomucinosis (DPAM)). Overall survival (OS) and disease-free survival (DFS) estimates were calculated using Kaplan-Meier survival curves. RESULTS: 109 patients with PC-A underwent laparotomy with curative intent. Of those, 92 underwent CRS plus HIPEC. Median follow-up was 42 months. The 5 and 10-year OS rates for the HIPEC group were 82.2% and 76.5%. The 5 and 10-year OS estimates for DPAM and PMCA-I subgroups were 100% and 100%, 78.1% and 72.9%, respectively. For the PMCA subgroup, the 3 and 5-year OS were 61.4% and 40.1%, respectively. The 5 and 10-year DFS estimates were 71.9% and 42.7%. CONCLUSION: CRS plus HIPEC with oxaliplatin represent an effective therapeutic approach for PC-A. Long term OS estimates for patients treated at our institution are encouraging.

Who Undergoes Cytoreductive Surgery and Perioperative Intraperitoneal Chemotherapy for Appendiceal Cancer? An Analysis of the National Cancer Database.

BACKGROUND: We sought to identify patterns of care for patients with appendiceal cancer and identify clinical factors associated with patient selection for multimodality treatment, including cytoreductive surgery and perioperative intraperitoneal chemotherapy (CRS/PIC). MATERIALS AND METHODS: National Cancer Database (NCDB) data from 2004 to 2014 of all diagnoses of appendiceal cancers were examined. We examined treatment modalities, as well as demographic, tumor-specific, and survival data. A multivariate logistic regression analysis was performed to determine the patient cohort most likely to receive CRS/PIC. Kaplan-Meier was used to estimate survival for all treatment groups. Significance was evaluated at P ≤ 0.05. RESULTS: We analyzed data on 18,055 patients. Nine thousand nine hundred ninety-two (55.3%) were treated with surgery only, 5848 (32.4%) received surgery and systemic chemotherapy, 1393 (7.71%) received CRS/PIC, 520 (2.88%) received chemotherapy alone, and 302 (1.67%) received neither surgery nor chemotherapy. Significant predictors of receiving CRS/PIC included male sex (OR 1.33, 95% CI: 1.11-1.59), white race (OR 2.00, 95% CI 1.40-2.86), non-Hispanic ethnicity (OR 1.92, 95% CI 1.21-3.05), private insurance (OR 1.52, 95% CI 1.26-1.84), and well-differentiated tumors (OR 4.25, CI: 3.39-5.32) (P < 0.05). Treatment with CRS/PIC was associated with a higher 5-year survival for mucinous malignancies, when compared to surgery alone (65.6% versus 62.4%, P < 0.01). Treatment with CRS/PIC was also associated with higher 5-year survival for well-differentiated malignancies, when compared to all other treatment modalities (74.9% versus 65.4%, P < 0.01). CONCLUSIONS: Patients were more likely to undergo CRS/PIC if they were male, white, privately insured, and with well-differentiated tumors. CRS/PIC was associated with improved survival in patients with mucinous and low-grade tumors.