Oncologic Outcomes of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Highly Selected Patients with Metastatic Pancreatic Ductal Adenocarcinoma

BACKGROUND

Peritoneal metastases (PM) from pancreatic ductal adenocarcinoma (PDAC) are currently treated with palliative systemic chemotherapy alone, with unsatisfactory results. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) may provide an oncologic benefit for highly selected patients.

PATIENTS AND METHODS

Patients with PDAC and isolated PM who completed ≥ 6 months of systemic chemotherapy with objective response between 2017 and 2022 were retrospectively reviewed. All patients met the inclusion/exclusion criteria as per our previously published PDAC CRS/HIPEC protocol. Patients who underwent CRS/HIPEC were compared with matched patients who underwent systemic therapy alone. Overall survival (OS) from diagnosis of PM and progression-free survival (PFS) from CRS/HIPEC was evaluated.

RESULTS

In total, 61 patients met the inclusion criteria: 38 underwent systemic therapy alone and 23 CRS/HIPEC. There were no differences in baseline prognostic factors, including age, sex, tumor size, tumor location, anatomic resectability, or serum cancer antigen (CA) 19-9 (p > 0.05). Median OS from PM diagnosis in patients who underwent systemic therapy alone was 19 months with 1, 2, and 3 year OS of 81%, 31%, and 8%, respectively. In contrast, median OS from PM diagnosis in patients who underwent CRS/HIPEC was 41 months with improved 1, 2, and 3 year OS of 91%, 66%, and 59%, respectively (p = 0.002). In the 21 patients who achieved complete cytoreduction (CC-0), no adjuvant therapy was administered and the median PFS was 17 months.

CONCLUSIONS

CRS/HIPEC in highly selected patients with PDAC and PM results in promising oncologic outcomes that are unlikely to be achieved with systemic chemotherapy alone. Further investigation is warranted and ongoing (NCT04858009).

Cytoreduction with Hyperthermic Intraperitoneal Chemoperfusion for Pancreatic Cancer with Low-Volume Peritoneal Metastasis: Results from a Prospective Pilot Study

INTRODUCTION

Resection of oligometastatic pancreatic ductal adenocarcinoma (PDAC) has historically been ineffective, however modern systemic chemotherapy has improved survival. Thus, re-evaluating safety and outcomes of surgical resection in selected patients with limited peritoneal metastasis (PM) warrants consideration.

METHODS

From 2018 to 2021, patients with PDAC and positive cytology or limited PM without extraperitoneal metastasis and who had an objective response to ≥ 6 months of systemic chemotherapy were enrolled. Patients underwent laparoscopic hyperthermic intraperitoneal chemotherapy (HIPEC) with cisplatin/mitomycin C. If amenable to a complete cytoreduction, patients went on to cytoreduction and HIPEC.

RESULTS

Overall, 18 patients were enrolled and received a median of 14 (interquartile range [IQR] 12-17) cycles of chemotherapy; 16 (89%) patients received chemoradiation. Laparoscopic HIPEC was completed in 17 patients, with a median length of stay of 1 day, and no grade III complications or hematological toxicities were observed. All 18 patients subsequently underwent a complete cytoreduction (CC-0) along with definitive treatment of the primary tumor, with formal resection (7/18), irreversible electroporation (IRE; 10/18), or intraoperative radiation therapy (IORT; 1/18). Median PCI was 2 (IQR 0-4), median LOS was 7 days (IQR 6-8), and 7 (39%) patients were readmitted. Eight (44%) patients experienced grade 3 or higher complications, including one 30-day mortality. At a median follow-up of 16 months, the median progression-free survival was 20 months and the median overall survival was 26 months.

CONCLUSION

Cytoreduction and HIPEC for selected patients with low-volume PM from PDAC is safe and feasible with favorable short-term outcomes. A phase II trial (NCT04858009) is now enrolling to further assess this multimodality approach in select patients.

Association of Common Medications and the Risk of Early-Onset Gastric Cancer: A Population-Based Matched Study

BACKGROUND

Early-onset gastric cancer (EOGC, age ≤ 60 years at diagnosis) now comprises >30% of new gastric cancers in the United States. It is hypothesized that chronic acid suppression with proton-pump inhibitors (PPIs) may promote tumorigenesis, while other medications including statins, nonsteroidal anti-inflammatory drugs (NSAIDs), metformin, and cyclooxygenase-2 (COX-2) inhibitors have been proposed as protective. We aimed to assess for an association between use of the aforementioned commonly prescribed medications and EOGC development.

METHODS

We used a population-based medical record linkage system, to identify cases of EOGC in Olmsted County, Minnesota, between January 1, 1995, and December 31, 2020. Patients were matched 1 : 1 with controls based on age at diagnosis, sex, smoking status, and body mass index (BMI). Conditional logistic regression was used to examine associations with the odds of EOGC development.

RESULTS

Ninety-six cases of EOGC were identified during the study period. On both univariate and multivariate regression analysis, there was no significant association between use of PPIs, statins, NSAIDs, or metformin and EOGC development. In a final multivariable model, there was a significant reduction in odds of EOGC with COX-2 inhibitor use for six months or more prior to cancer diagnosis (OR = 0.39, 95% CI 0.16-0.94).

CONCLUSION

In this retrospective, population-based study of individuals in Olmsted County, MN, we found significantly reduced odds of EOGC development associated with COX-2 inhibitor use for six months or more prior to diagnosis, but no association between EOGC development and use of PPIs and other commonly prescribed medications.

The impact of HIPEC vs. EPIC for the treatment of mucinous appendiceal carcinoma: a study from the US HIPEC collaborative

INTRODUCTION

Mucinous appendiceal carcinoma is a rare malignancy that commonly spreads to the peritoneum leading to peritoneal metastases. Complete cytoreduction with perioperative intraperitoneal chemotherapy (PIC) is the mainstay of treatment, administered as either hyperthermic intra peritoneal chemotherapy (HIPEC) or early post-operative intraperitoneal chemotherapy (EPIC). Our goal was to assess the perioperative and long term survival outcomes associated with these two PIC methods.

MATERIALS AND METHODS

Patients with mucinous appendiceal carcinoma were identified in the US HIPEC Collaborative database from 12 academic institutions. Patient demographics, clinical characteristics, and survival outcomes were compared among patients who underwent HIPEC vs. EPIC with inverse probability weighting (IPW) used for adjustment.

RESULTS

Among 921 patients with mucinous appendiceal carcinoma, 9% underwent EPIC while 91% underwent HIPEC. There was no difference in Grade III-V complications between the two groups (18.5% for HIPEC vs. 15.0% for EPIC, p=.43) though patients who underwent HIPEC had higher rates of readmissions (21.2% vs. 8.8%, p<.01). Additionally, PIC method was not an independent predictor for overall survival (OS) or recurrence-free survival (RFS) after adjustment on multivariable analysis.

CONCLUSIONS

Among patients with mucinous appendiceal carcinoma, both EPIC and HIPEC appear to be associated with similar perioperative and long-term outcomes.

Comparison of open and closed hyperthermic intraperitoneal chemotherapy: Results from the United States hyperthermic intraperitoneal chemotherapy collaborative

BACKGROUND

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal carcinomatosis can be performed in two ways: Open or closed abdominal technique.

AIM

To evaluate the impact of HIPEC method on post-operative and long-term survival outcomes.

METHODS

Patients undergoing CRS with HIPEC from 2000-2017 were identified in the United States HIPEC collaborative database. Post-operative, recurrence, and overall survival outcomes were compared between those who received open vs closed HIPEC.

RESULTS

Of the 1812 patients undergoing curative-intent CRS and HIPEC, 372 (21%) patients underwent open HIPEC and 1440 (79%) underwent closed HIPEC. There was no difference in re-operation or severe complications between the two groups. Closed HIPEC had higher rates of 90-d readmission while open HIPEC had a higher rate of 90-d mortalities. On multi-variable analysis, closed HIPEC technique was not a significant predictor for overall survival (hazards ratio: 0.75, 95% confidence interval: 0.51-1.10, P = 0.14) or recurrence-free survival (hazards ratio: 1.39, 95% confidence interval: 1.00-1.93, P = 0.05) in the entire cohort. These findings remained consistent in the appendiceal and the colorectal subgroups.

CONCLUSION

In this multi-institutional analysis, the HIPEC method was not independently associated with relevant post-operative or long-term outcomes. HIPEC technique may be left to the discretion of the operating surgeon.

Impact of Neoadjuvant Chemotherapy on the Outcomes of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Colorectal Peritoneal Metastases: A Multi-Institutional Retrospective Review

Cytoreductive surgery (CRS) with or without hyperthermic intraperitoneal chemotherapy (HIPEC) is associated with improved survival for patients with colorectal peritoneal metastases (CR-PM). However, the role of neoadjuvant chemotherapy (NAC) prior to CRS-HIPEC is poorly understood. A retrospective review of adult patients with CR-PM who underwent CRS+/-HIPEC from 2000–2017 was performed. Among 298 patients who underwent CRS+/-HIPEC, 196 (65.8%) received NAC while 102 (34.2%) underwent surgery first (SF). Patients who received NAC had lower peritoneal cancer index score (12.1 + 7.9 vs. 14.3 + 8.5, p = 0.034). There was no significant difference in grade III/IV complications (22.4% vs. 16.7%, p = 0.650), readmission (32.3% vs. 23.5%, p = 0.114), or 30-day mortality (1.5% vs. 2.9%, p = 0.411) between groups. NAC patients experienced longer overall survival (OS) (median 32.7 vs. 22.0 months, p = 0.044) but similar recurrence-free survival (RFS) (median 13.8 vs. 13.0 months, p = 0.456). After controlling for confounding factors, NAC was not independently associated with improved OS (OR 0.80) or RFS (OR 1.04). Among patients who underwent CRS+/-HIPEC for CR-PM, the use of NAC was associated with improved OS that did not persist on multivariable analysis. However, NAC prior to CRS+/-HIPEC was a safe and feasible strategy for CR-PM, which may aid in the appropriate selection of patients for aggressive cytoreductive surgery.

Advancements and challenges in treating advanced gastric cancer in the West

Gastric cancer is a leading cause of cancer incidence and death worldwide. Patients with advanced gastric cancer benefit from a multi-modality treatment regimen. Sound oncologic resection with negative margins and complete lymphadenectomy plays a crucial role in long-term survival for patients with resectable disease. The utilization of minimally invasive techniques for gastric cancer has been slowly increasing and is proving to be both technically and oncologically safe. Perioperative chemotherapy is the current standard of care for advanced gastric cancer. A variety of chemotherapy regimens have been used with the combination of docetaxel, oxaliplatin, 5-fluorouracil, and leucovorin being the current recommendation given its superior ability to induce a complete pathologic response and prolong survival. The use of radiation has been more controversial with its optimal place in the treatment sequence being unclear. There are current ongoing studies assessing the impact of radiation as an adjunct or in place of chemotherapy. Targeted treatments (e.g., trastuzumab for human epidermal growth factor receptor 2 positive tumors and pembrolizumab for programmed death-ligand 1 positive tumors) are showing promise and are part of a continued emphasis on individualized care. Intraperitoneal chemotherapy may also play a role in preventing peritoneal recurrences for patients with high risk lesions. The treatment of patients with advanced gastric cancer in the West continues to advance and improve with a better understanding of optimal treatment sequences and the utilization of personalized treatment regimens.

Early-onset gastric cancer is a distinct disease with worrisome trends and oncogenic features

BACKGROUND

Overall the incidence of gastric cancer is declining in the United States; however, the incidence of early-onset gastric cancer is increasing. We sought to elucidate clinical and genomic characteristics and risk factors for early-onset gastric cancer compared with late-onset gastric cancer.

METHODS

We utilized the Surveillance, Epidemiology, and End Results database (1973-2015), the Behavioral Risk Factor Surveillance Survey, and The Cancer Genome Atlas to characterize early-onset gastric cancer.

RESULTS

The incidence of early-onset gastric cancer increased during the study period and now comprises >30% of all gastric cancer in the United States. Early-onset gastric cancer was associated with higher grade (55.2 vs 46.9%), signet-ring cells (19.0 vs 10.4%), diffuse histology (25.7 vs 15.0%), and metastatic disease (49.5 vs 40.9%, all P < .01) compared with late-onset gastric cancer. Early-onset gastric cancer was more likely to be Epstein-Barr virus (7.7 vs 5.1%) or genomically stable (22.5 vs 8.1%) subtype, whereas late-onset gastric cancer was more likely to be microsatellite instability subtype (18.6 vs 5.6%; all P < .01). Risk factors for gastric cancer were less correlated with early-onset gastric cancer compared with late-onset gastric cancer.

CONCLUSION

The incidence of early-onset gastric cancer has been steadily increasing in the United States, comprising >30% of new gastric cancer cases today. Early-onset gastric cancer is genetically and clinically distinct from traditional gastric cancer. Additional investigations are warranted to better understand this alarming phenomenon.

Radiation Therapy for Retroperitoneal Sarcomas: Influences of Histology, Grade, and Size

Perioperative radiation therapy (RT) has been associated with reduced local recurrence in patients with retroperitoneal sarcomas (RPS); however, selection criteria remain unclear. We hypothesized that perioperative RT would improve survival in patients with RPS and would be associated with pathological factors. The National Cancer Database (NCDB) from 2004 to 2012 was reviewed for patients with nonmetastatic RPS undergoing curative intent resection. Tumor size was dichotomized at 15 cm based on 8th edition American Joint Committee on Cancer (AJCC) staging. Patients with the highest comorbidity score were excluded. Unadjusted Kaplan–Meier and adjusted Cox proportional hazards modeling analyzed overall survival (OS). Multivariable logistic regression modeled margin positivity. A total of 2,264 patients were included; 727 patients (32.1%) had perioperative radiation in whom 203 (9.0%) had radiation preoperatively. Median (IQR) RPS size was 17.5 [11.0–27.0] cm. Histopathology was high grade in 1048 patients (43.7%). Multivariable analysis revealed that perioperative radiation was independently associated with decreased mortality (HR 0.72, 95% confidence intervals (CIs) 0.62–0.84, p < 0.001), and preoperative RT was associated with reduced margin positivity (HR 0.72, 95% CI 0.53–0.97, p=0.032). Stratified survival analysis showed that radiation was associated with prolonged median OS for RPS that were high-grade (64.3 vs. 43.6 months, p < 0.001), less than 15 cm (104.1 vs. 84.2 months, p=0.007), and leiomyosarcomatous (104.8 vs. 61.8 months, p < 0.001). Perioperative radiation is independently associated with decreased mortality in patients with high-grade, less than 15 cm, and leiomyosarcomatous tumors. Preoperative radiation is independently associated with margin-negative resection. These data support the selective use of perioperative radiation in the multidisciplinary management of RPS.

Optimizing outcomes for patients with gastric cancer peritoneal carcinomatosis

Peritoneal carcinomatosis (PC) from gastric cancer has traditionally been considered a terminal progression of the disease and is associated with poor survival outcomes. Positive peritoneal cytology similarly worsens the survival of patients with gastric cancer and treatment options for these patients have been limited. Recent advances in multimodality treatment regimens have led to innovative ways to care for and treat patients with this disease burden. One of these advances has been to use neoadjuvant therapy to try and convert patients with positive cytology or low-volume PC to negative cytology with no evidence of active peritoneal disease. These strategies include the use of neoadjuvant systemic chemotherapy alone, using neoadjuvant laparoscopic heated intraperitoneal chemotherapy (NLHIPEC) after systemic chemotherapy, or using neoadjuvant intraperitoneal and systemic chemotherapy (NIPS) in a bidirectional manner. For patients with higher volume PC, cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have been mainstays of treatment. When used together, CRS and HIPEC can improve overall outcomes in properly selected patients, but overall survival outcomes remain unacceptably low. The extent of peritoneal disease, commonly measured by the peritoneal carcinomatosis index (PCI), and the completeness of cytoreduction, has been shown to greatly impact outcomes in patients undergoing CRS and HIPEC. The uses of NLHIPEC and NLHIPEC plus NIPS have both been shown to decrease the PCI and thus increase the opportunity for complete cytoreduction. Newer therapies like pressurized intraperitoneal aerosol chemotherapy and immunotherapy, such as catumaxomab, along with improved systemic chemotherapeutic regimens, are being explored with great interest. There is exciting progress being made in the management of PC from gastric cancer and its' treatment is no longer futile.

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.