Metastasis and the Microbiome: The Impact of Bacteria in Disseminated Colorectal Cancer.

Metastasis remains a leading cause of mortality for patients with solid tumors. An expanding body of literature suggests interplay between the host, gut, and tumoral microbiomes may play a role in cancer initiation and distant dissemination. These associations have been particularly well-studied in colorectal cancer, where gut dysbiosis and an endotoxin-induced inflammatory milieu foster premalignant polyp formation, setting the stage for carcinogenesis. Subsequent violation of the gut vascular barrier enables dissemination of bacterial agents to sites such as the liver, where they contribute to establishment of pre-metastatic niches, which promote tumor cell extravasation and metastatic outgrowth. Intriguingly, breakdown of this vascular barrier has been shown to be aided by the presence of tumoral bacteria. The presence of similar species, including Fusobacterium nucleatum and Escherichia Coli, in both primary and metastatic colorectal tumors, supports this hypothesis and their presence is associated with chemotherapy resistance and an overall poor prognosis. Specific gut microbial populations are also associated with differential response to immunotherapy, which has a growing role in microsatellite unstable colorectal cancers. Recent work suggests that modulation of gut microbiome using dietary modification, targeted antibiotics, or fecal microbiota transplantation may improve response to immunotherapy and oncologic outcomes. Elucidation of the precise mechanistic links between the microbiome and cancer dissemination will open the doors to additional therapeutic possibilities.

TP53 Alteration and Its Effect on Pathologic Response Are Associated with Survival after Resection of Colorectal Liver Metastases.

The aims of this study were to assess the effect of known gene alterations (RAS, TP53, APC, SMAD4, BRAF, and FBXW7) on pathologic response (PR) and their combined association with survival in patients with colorectal liver metastases (CLM). From a prospectively maintained database, we collected data on 458 patients who underwent curative-intent hepatectomy after receiving the first-line preoperative chemotherapy between 2004 and 2020. Major PR was defined as tumor viability of less than 50% in all tumors. Multivariate logistic regression revealed that oxaliplatin-containing regimen (OR: 2.54, 95% CI: 1.58-4.07, P < 0.001), bevacizumab-containing regimen (OR: 2.15, 95%CI: 1.36-3.39, P = 0.001), and TP53 alteration (OR: 0.42, 95%CI: 0.27-0.66, P < 0.001) were independently associated with major PR. Multivariate Cox regression also revealed that patients with TP53 wild-type and major PR (HR: 0.49, 95%CI: 0.31-0.77, P = 0.002) and those with TP53 alteration and major PR (HR: 0.70, 95%CI: 0.49-1.00, P = 0.048) had significantly better overall survival compared to those with minor PR. Further studies targeting the association of TP53 with PR and survival can help clarify the role of TP53 in CLM.

Hepatectomy Before Primary Tumor Resection as Preferred Approach for Synchronous Liver Metastases from Rectal Cancer.

BACKGROUND: For patients with synchronous liver metastases (LM) from rectal cancer, a consensus on surgical sequencing is lacking. We compared outcomes between the reverse (hepatectomy first), classic (primary tumor resection first), and combined (simultaneous hepatectomy and primary tumor resection) approaches. METHODS: A prospectively maintained database was queried for patients with rectal cancer LM diagnosed before primary tumor resection who underwent hepatectomy for LM from January 2004 to April 2021. Clinicopathological factors and survival were compared between the three approaches. RESULTS: Among 274 patients, 141 (51%) underwent the reverse approach; 73 (27%), the classic approach; and 60 (22%), the combined approach. Higher carcinoembryonic antigen level at LM diagnosis and higher number of LM were associated with the reverse approach. Combined approach patients had smaller tumors and underwent less complex hepatectomies. More than eight cycles of pre-hepatectomy chemotherapy and maximum diameter of LM > 5 cm were independently associated with worse overall survival (OS) (p = 0.002 and 0.027, respectively). Although 35% of reverse-approach patients did not undergo primary tumor resection, OS did not differ between groups. Additionally, 82% of incomplete reverse-approach patients ultimately did not require diversion during follow-up. RAS/TP53 co-mutation was independently associated with lack of primary resection with the reverse approach (odds ratio: 0.16, 95% CI 0.038-0.64, p = 0.010). CONCLUSIONS: The reverse approach results in survival similar to that of combined and classic approaches and may obviate primary rectal tumor resections and diversions. RAS/TP53 co-mutation is associated with a lower rate of completion of the reverse approach.

Optimizing the future liver remnant: Portal vein embolization, hepatic venous deprivation, and associating liver partition and portal vein ligation for staged hepatectomy.

Preservation of an adequate future liver remnant is paramount when planning any major liver resection and is of particular concern in the setting of bilateral colorectal liver metastases. Procedures including portal vein embolization and hepatic venous deprivation for one- or two-stage hepatectomy, and associating liver partition and portal vein ligation for staged hepatectomy have been developed to enable curative-intent hepatectomy for colorectal liver metastases in patients with an initially insufficient future liver remnant.

Differential Gains in Surgical Outcomes for High-Risk vs Low-Risk Pancreaticoduodenectomy with Successive Refinements of Risk-Stratified Care Pathways.

BACKGROUND: The use of risk-stratified pancreatectomy care pathways (RSPCPs) is associated with reduced length of stay (LOS). This study sought to evaluate the impact of successive pathway revisions with the hypothesis that high-risk patients require iterative pathway revisions to optimize outcomes. STUDY DESIGN: A prospectively maintained database (October 2016 to December 2021) was evaluated for pancreaticoduodenectomy patients managed with RSPCPs preoperatively assigned based on postoperative pancreatic fistula (POPF) risk. Launched in October 2016 (version [V] 1), RSPCPs were optimized in February 2019 (V2) and November 2020 (V3). Targeted pathway components included earlier nasogastric tube removal, diet advancement, reduced intravenous fluids and opioids, institution-specific drain fluid amylase cutoffs for early day 3 removal, and patient education. Primary outcome was LOS. Secondary outcomes included major complication (Accordion grade 3+), POPF (International Study Group for Pancreatic Surgery Grade B/C), and delayed gastric emptying (DGE). RESULTS: Of 481 patients, 234 were managed by V1 (83 high-risk), 141 by V2 (43 high-risk), and 106 by V3 (43 high-risk). Median LOS reduction was greatest in high-risk patients with a 7-day reduction (pre-RSPCP, 12 days; V1, 9 days; V2, 7 days; V3, 5 days), compared with low-risk patients (pre-pathway, 10 days; V1, 6 days; V2, 5 days; V3, 4 days). Complications decreased significantly among high-risk patients (V1, 45%; V2, 33%; V3, 19%; p < 0.001), approaching rates in low-risk patients (V1, 21%; V2, 20%; V3, 14%). POPF (V1, 33%; V2, 23%; V3, 16%; p < 0.001) and DGE (V1, 23%; V2, 22%; V3, 14%; p < 0.001) improved among high-risk patients. CONCLUSIONS: Risk-stratified pancreatectomy care pathways are associated with reduced LOS, major complication, Grade B/C fistula, and DGE. The easiest gains in surgical outcomes are generated from the immediate improvement in the patients most likely to be fast-tracked, but high-risk patients benefit from successive application of the learning health system model.

Neoadjuvant chemotherapy for high-risk intrahepatic cholangiocarcinoma - does pathologic response mean better outcomes?

BACKGROUND: The role of neoadjuvant chemotherapy (NAC) in the management of intrahepatic cholangiocarcinoma (ICC) remains unknown. We sought to evaluate our experience treating high-risk ICC with NAC and to determine the prognostic significance of pathologic response. METHODS: Patients with ICC treated with NAC and surgery were analyzed using a prospectively maintained database. Pathologic response was graded by a blinded pathologist. Clinicopathologic/treatment variables were evaluated for associations with survival. RESULTS: Among 45 patients who received NAC followed by hepatectomy for high-risk ICC, 32(71%) were considered stage III, and 6(13%) were considered stage IV at time of diagnosis. Major response was identified in 39% of cases, including 2 with pathologic complete response. Patients with major response had a longer median NAC duration than patients with minor response (6 vs 4cycles, P=0.02). Regimen (gemcitabine/cisplatin vs gemcitabine/cisplatin/nab-paclitaxel) was not associated with response rate. Median recurrence-free (RFS) and overall survival (OS) were 11 and 45 months. Pathologic response was not associated with improved survival. CONCLUSION: Pathologic response to NAC was not associated with survival in this highly selected cohort. Nonetheless, the extended OS experienced by these high-risk patients is encouraging and suggests that NAC may help select patients who stand to benefit from aggressive resection.

Symptom Burden in Patients with Malignant Bowel Obstruction Treated With or Without Surgery.

BACKGROUND: Gastrointestinal obstruction is the most common indication for palliative surgical consultation. We sought to assess patient-reported outcomes and survival after surgical and nonsurgical treatment of malignant bowel obstruction. STUDY DESIGN: This was a prospective observational study enrolling patients with advanced malignancy who underwent surgical consultation at a tertiary cancer center. Patient-reported outcomes were evaluated using a previously validated inventory, the MD Anderson Symptom Inventory-Gastrointestinal Obstruction (MDASI-GIO), administered at enrollment and 7 other time points for up to 90 days. RESULTS: We enrolled 125 patients, of whom 37 underwent surgery and 88 did not. Patients treated nonsurgically were more likely to have carcinomatosis on imaging (71% vs 49%, p = 0.02). Pain medicine, palliative care, and chaplaincy consultations occurred in 17%, 30%, and 15% of patients within the first month of enrollment. Higher mean symptom scores were noted by surgical patients, although the only single scores with effect sizes 0.5 or greater were symptom interference with general activity and work. The composite score for interference in work, activity, and walking had the largest effect size at -0.37, indicating greater interference in patients undergoing surgery. Patients selected for surgery had extended overall survival (median 15 vs 3 months, p < 0.01). Carcinomatosis, palliative care evaluation, and venting gastrostomy tube were associated with increased risk of death, and ability to receive subsequent chemotherapy and surgical management were positive prognostic indicators. CONCLUSIONS: In this first study evaluating patient-reported outcomes after treatment for malignant bowel obstruction, we found that selection for surgical treatment was associated with improved survival, but also more symptom interference in general activities and work. These results may be useful in palliative surgical decision-making and informing patients during consultation for malignant bowel obstruction.

Robot-assisted liver resection: the real benefit so far.

BACKGROUND: Minimally invasive liver resection is associated with lower perioperative morbidity and shorter hospital stay. However, the added benefit of the robotic platform over conventional laparoscopy is a matter of ongoing investigation. PURPOSE: The purpose of this narrative review is to provide an up-to-date and balanced evaluation of the benefits and shortcomings of robotic liver surgery for the modern hepatobiliary surgeon. CONCLUSIONS: Advantages of a robotic approach to liver resection include a shortened learning curve, the ability to complete more extensive or complex minimally invasive operations, and integrated fluorescence guidance. However, the robotic platform remains limited by a paucity of parenchymal transection devices, complete lack of haptic feedback, and added operating time associated with docking and instrument exchange. Like laparoscopic hepatectomy, robotic hepatectomy may provide patients with more rapid recovery and a shorter hospital stay, which can help offset the substantial costs of robot acquisition and maintenance. The oncologic outcomes of robotic hepatectomy appear to be equivalent to laparoscopic and open hepatectomy for appropriately selected patients.

A Microcosm of Disparities in Breast Cancer: Comparison Between a Private Hospital and a Safety-Net County Hospital Within Los Angeles County.

BACKGROUND: Breast cancer survival is improving due to early detection and treatment advances. However, racial/ethnic differences in tumor biology, stage, and mortality remain. The objective of this study was to analyze presumed disparities at a local level. METHODS: Breast cancer patients at a county hospital and private hospital from 2010 to 2012 were retrospectively reviewed. Demographic, clinical, pathologic, and surgical data were collected. Comparisons were made between hospital cohorts and between racial/ethnic groups from both hospitals combined. RESULTS: 754 patients were included (322 from county hospital and 432 from private hospital). All patients were female. The median age was 54 years at county hospital and 60 years at private hospital (P < .0001). Racial/ethnic minorities comprised 85% of county hospital patients vs. 12% of private hospital patients (P < .0001). County hospital patients had a higher grade, clinical/pathologic stage, HER2-positive rate, and mastectomy rate. Compared to other racial/ethnic groups, non-Hispanic white women were more likely to have lower grade and ER-positive tumors. Hispanic/Latina women were younger and were more likely to have HER2-positive tumors. Both Hispanic/Latina and non-Hispanic black women presented at higher clinical stages and were more likely to undergo neoadjuvant chemotherapy and mastectomy. DISCUSSION: At county hospital compared to private hospital, the proportion of racial/ethnic minorities was higher, and patients presented at younger ages with more aggressive tumors and more advanced disease. The racial/ethnic disparities that were identified locally are largely consistent with those identified in national database studies. These marked differences at hospitals within a diverse city highlight the need for further research into the disparities.

Characterization of alveolar soft part sarcoma using a large national database.

BACKGROUND: Alveolar soft part sarcoma is a rare, histologic subtype of soft tissue sarcoma that remains poorly defined. We aimed to describe patient characteristics and treatment patterns and to examine factors associated with survival for patients with alveolar soft part sarcoma. METHODS: After identifying patients with alveolar soft part sarcoma in the National Cancer Database, we recorded their clinicopathologic characteristics. Univariable log-rank survival analysis and Cox proportional hazards model were employed. For context, survival comparisons were included for patients with other sarcoma subtypes. RESULTS: Overall, 293 patients with alveolar soft part sarcoma were identified. Interestingly, patients with head and neck tumors were least likely to present with distant disease (40%, P = .025). The majority of patients underwent resection (n = 183, 63%). Among those, no predictors of lesser survival were identified other than the presence of metastases (hazard ratio 6.04, P ≤ .001). Patients with stage IV alveolar soft part sarcoma who underwent resections experienced improved survival relative to similar patients with more common subtypes of soft tissue sarcomas (P ≤ .001). CONCLUSION: Alveolar soft part sarcoma is exceedingly rare, and patients often present with metastases. Primary tumors can occur anywhere in the body, and location impacts the rates of metastases at presentation. Resection is associated with a favorable survival advantage when compared to other, more common histologic subtypes of soft tissue sarcomas.

Gallbladder squamous cell carcinoma: An analysis of 1084 cases from the National Cancer Database.

BACKGROUND/OBJECTIVES: Gallbladder squamous cell carcinoma (SCC) is an uncommon malignancy whose rarity has made it particularly challenging to study. We utilized a national database to shed light on the clinicopathologic characteristics, management patterns, and survival associated with these tumors. METHODS: Patients with gallbladder SCC were identified in the National Cancer Database. Clinicopathologic and treatment characteristics were recorded and compared with adenocarcinoma for context. Univariate and multivariable survival analyses were completed for patients who underwent resection. RESULTS: Overall, 1084 patients with SCC and 23 958 patients with adenocarcinoma were identified. Compared with those with adenocarcinoma, patients with SCC had higher grade tumors (P < .001) and were diagnosed at a later stage (P < .001). Patients with SCC were more likely to undergo radical cholecystectomy (17% vs 9%; P < .001), but had a higher rate of margin positivity (36% vs 29%; P < .001). SCC histology was associated with worse survival compared with adenocarcinoma, even after adjusting for R0 resections (13 vs 29 months; P < .001). On multivariable analysis, SCC histology was independently associated with abbreviated survival (P = .003). CONCLUSIONS: Gallbladder SCCs are aggressive cancers that often present at an advanced stage. Complete surgical extirpation should be pursued when feasible. However, prognosis is worse than that of adenocarcinoma, even after R0 resection.

Targeting CA 19-9 with a humanized monoclonal antibody at the time of surgery may decrease recurrence rates for patients undergoing resections for pancreatic cancer, cholangiocarcinoma and metastatic colorectal cancer.

Operable gastrointestinal cancers continue to pose significant challenges. Radical resections are rarely curative, and chemotherapy is able to reduce tumor recurrence for only a small percentage of patients. Despite the obvious advantages of extirpation of the identifiable tumor(s), the inflammatory milieu that accompanies surgery and the obligate time off cytotoxic agents allows for activation of remote quiescent disseminated tumor cells, leading to metastatic recurrence. We are conducting a study to determine the safety and efficacy of immediate peri-operative MVT-5873, a cytotoxic monoclonal antibody targeting carbohydrate antigen 19-9 (CA 19-9), in patients undergoing resections pancreatic cancer, cholangiocarcinoma or metastatic colorectal cancer to the liver. Eligible patients will receive a single dose of MVT-5873 three days before resection and four post-operative infusions, before beginning standard adjuvant regimens. MVT-5873 is a human IgG1 antibody isolated from a patient following immunization with a sLea-KLH vaccine. MVT-5873 demonstrated cell surface binding in sLea positive human tumor lines and has been shown to be potent in complement-dependent cytotoxicity assays and antibody-dependent cell mediated cytotoxicity assays. In patients with metastatic CA 19-9 producing pancreatic adenocarcinoma, MVT-5873 treatment has been shown to decrease serum CA 19-9 levels and prevent tumor progression. The use of perioperative MVT-5873 has the potential to reduce recurrence rates and prolong survival after resection. This trial may open the door for investigation of additional and/or synergistic agents in the immediate peri-operative period and usher in a new paradigm in the management of surgically treated cancers. TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT03801915?term=MVT&rank=3.

Stage and disease-free interval help select patients for surgical management of locally recurrent and metastatic adrenocortical carcinoma.

BACKGROUND AND OBJECTIVES: Chemotherapeutic options for patients with recurrent/metastatic adrenocortical carcinoma (ACC) are limited, leading to consideration for surgical management. We sought to determine characteristics associated with an unequivocal survival benefit amongst patients undergoing re-resection or metastasectomy. METHODS: Patients who underwent surgery for recurrent/metastatic ACC were identified and stratified into two groups: those with postoperative survival comparable with what has been reported with chemotherapy alone (<12 months) and those surviving twice that duration (>24 months). Those who survived between 12 and 24 months were excluded, as the objective was to characterize patients who most distinctly benefited from resection. Clinicopathologic and treatment variables were evaluated for associations with survival. RESULTS: Forty-three patients survived more than 24 months and 15 patients died less than 12 months after reoperation. Tumor stage (odds ratio [OR], 0.66; 95% confidence interval [CI], 0.45-0.96) and disease-free interval (DFI; OR, 3.23; 95% CI, 1.68-6.22) were associated with prolonged survival. Tumor size, hormonal status, resection margin, and treatment with chemotherapy, radiation, and mitotane were not associated with prolonged survival. Patients who survived more than 24 months underwent more procedures for subsequent recurrences (median 4 vs 2; P < .001). CONCLUSION: Stage and DFI can help select optimal candidates for resection of recurrent/metastatic ACC. Patients selected for surgical management should be informed of the likelihood of requiring multiple interventions.

Resection and chemotherapy is the optimal treatment approach for patients with clinically node positive intrahepatic cholangiocarcinoma.

BACKGROUND: Clinically lymph node positive (cLNP) intrahepatic cholangiocarcinoma (ICC) carries a poor prognosis, without clear management guidelines for the practicing clinician. We sought to evaluate current practice patterns for cLNP ICC, including associations with survival. METHODS: The National Cancer Database was queried for patients with cLNP ICC, without extrahepatic metastases. RESULTS: We identified 1023 patients with cLNP ICC, 77%% (n = 784) of whom received chemotherapy alone. Resection was undertaken in 23% (n = 239) of patients and was most commonly utilized in combination with chemotherapy (n = 150). Median survival for all patients was 13.6 months. Patients undergoing resection in combination with chemotherapy were associated with an improved survival (22.5 months) as compared to those patients receiving chemotherapy alone (11.9 months) or resection alone (12.4 months) (p < 0.01). Finally, we compared the survival of patients with cLNP ICC with that of patients with pathologically proved lymph node positive (pLNP) ICC, all of whom were treated with resection with chemotherapy, and found no difference in survival (22.5 months-19.3 months, p = 0.99, respectively). CONCLUSIONS: While the decision to pursue resection for ICC is multifactorial and patient specific, the presence of clinically positive LNs should not represent a contraindication.

Disease-free interval and tumor functional status can be used to select patients for resection/ablation of liver metastases from adrenocortical carcinoma: insights from a multi-institutional study.

BACKGROUND: Adrenocortical carcinoma (ACC) is an aggressive malignancy that frequently metastasizes to the liver. Given the limitations of systemic therapy in this setting, we sought to determine characteristics associated with a two-fold increase in survival with resection/ablation compared to that reported with chemotherapy alone (∼12 months). METHODS: Patients who underwent resection/ablation at our institutions for ACC liver metastases were identified. Those who survived 12-24 months after metastasectomy were excluded, as the aim was to characterize patients who most clearly benefited from these procedures. Clinicopathologic and treatment characteristics were assessed for associations with survival. RESULTS: Sixty-two patients met inclusion criteria, of whom 44 survived >24 months and 18 survived <12 months. Patients with extended survival were less likely to have functioning tumors (p = 0.047), had fewer liver metastases (p = 0.047), and a longer disease-free interval (DFI) (median 17.6 vs 2.3 months, p < 0.0001). On multivariable analysis, DFI (OR = 1.33, 95% CI = 1.12-1.58) and non-functioning tumor (OR = 0.13, 95% CI = 0.13-0.56) were independently associated with prolonged survival. CONCLUSION: Metastasectomy/ablation should be considered for patients with ACC liver metastases. DFI and tumor functional status may be useful in selecting optimal candidates for these procedures.

Tumor grade may be used to select patients with multifocal hepatocellular carcinoma for resection.

BACKGROUND: While resection is a recommended treatment for patients with stage 1 hepatocellular carcinoma (HCC), it remains controversial for multifocal disease. We sought to identify patients with multifocal HCC with survival after resection similar to patients with clinical stage 1 HCC. METHODS: The National Cancer Database was queried to identify patients that underwent resection for HCC. RESULTS: In this study, 2990 patients with a single tumor, and 1087 patients with multifocal disease confined to one lobe underwent resection. In the multifocal cohort, patients with clinical stage 3 (HR 1.54, CI 1.31-1.81, p < 0.0001) or 4 (HR 2.27, CI 1.57-3.29, p < 0.0001) disease, and those with moderately-differentiated (HR 1.32, CI 1.06-1.64, p = 0.012) or poorly differentiated/undifferentiated tumors (HR 1.53, CI 1.20-1.95, p = 0.0006) were associated with worse overall survival (OS). There was no difference in OS between patients with well-differentiated clinical stage 2 multifocal HCC and those with all grades of clinical stage 1 HCC (median of 84.8 (CI 66.3-107.2) vs 76.2 months (CI 71.2-81.3), respectively, p = 0.356). CONCLUSIONS: Patients with well-differentiated, clinical stage 2 multifocal HCC confined to one lobe experience similar OS following hepatic resection to patients with clinical stage 1 disease. These findings may impact the management of select patients with multifocal HCC.