Conditional disease‐free survival after curative‐intent liver resection for neuroendocrine liver metastasis

Treatment strategies for neuroendocrine liver metastases: a systematic review

BACKGROUND

Gastroenteropancreatic neuroendocrine tumors are often diagnosed when metastatic. The liver is the main site of metastases. Unfortunately, optimal management of neuroendocrine liver metastases remains a topic of debate. The aim of this study was to make a systematic review of the current literature about the results of the different treatments of neuroendocrine liver metastases.

METHODS

A systematic review was conducted for English language publications from 1995 to 2021. Outcomes were analyzed according to survival, disease-free survival, and in the case of systemic therapies, progression-free survival.

RESULTS

5509 patients were analyzed in the review. 67% of patients underwent surgery achieving 5 years overall survival despite only 30% percent without a recurrence. 60% of patients that had received a transplant reached 5 years survival with a low disease-free survival rate (20%). Five-year survival rate was 36.2% for patients undergoing loco-regional therapies.

CONCLUSION

Surgical resection is the best treatment when metastases are resectable, with the highest rate of survival, although liver transplantation shows good results for patients not eligible for surgery. Loco-regional therapies may be useful when surgical resection is contraindicated, or selectively used as a bridge to surgery or transplantation. Systemic therapies are indicated in patients for whom curative treatment cannot be obtained.

A novel prognostic time window based on conditional survival and outcomes analyses of primary liver cancer patients

Background

Liver cancer is one of the most deadly and prevalent cancers. A routine follow‐up plan for liver cancer is crucial but limited. In the present study, we aimed to disclose possible risk factors and critical survival time windows for primary liver cancer.

Methods

We enrolled 692 liver cancer patients from Sun Yat‐sen University Cancer Center (SYSUCC). Univariate and multivariate logistic regression analyses of cirrhosis and recurrence were conducted. A meta‐analysis was utilized to validate an indication of creatinine (CRE) in recurrence. Conditional survival analysis was performed using the Kaplan–Meier method. The results were further verified by the SYSUCC validation cohort and Surveillance, Epidemiology, and End Results (SEER) validation cohort.

Results

Our results indicated that A/G, history of hepatitis, history of alcohol consumption and platelet (PLT) might be potential prognostic factors for cirrhosis in liver cancer patients. CRE was significantly correlated with recurrence due to various therapies, especially after transarterial embolization. Moreover, 1.5 years to 2 years may be a critical time window for deterioration in survival rate based on the conditional survival analysis.

Conclusion

A/G, history of hepatitis, alcohol consumption and PLT may be potential prognostic factors for cirrhosis in liver cancer patients. More attention should be focused on the renal function when treating the patients due to the significant role of CRE. 1.5 years to 2 years is a critical time window for deterioration in survival rate for liver cancer patients that contributes to determining the optimal follow‐up plan in the future.

Conditional probability of graft survival in liver transplantation using donation after circulatory death grafts - a retrospective study

The use of livers from donation after circulatory death (DCD) is historically characterized by increased rates of biliary complications and inferior short-term graft survival (GS) compared to donation after brain death (DBD) allografts. This study aimed to evaluate the dynamic prognostic impact of DCD livers to reveal whether they remain an adverse factor even after patients survive a certain period following liver transplant (LT). This study used 74 961 LT patients including 4065 DCD LT in the scientific registry of transplant recipients from 2002-2017. The actual, 1 and 3-year conditional hazard ratio (HR) of 1-year GS in DCD LT were calculated using a conditional version of Cox regression model. The actual 1-, 3-, and 5-year GS of DCD LT recipients were 83.3%, 73.3%, and 66.3%, which were significantly worse than those of DBD (all P < 0.01). Actual, 1-, and 3-year conditional HR of 1-year GS in DCD compared to DBD livers were 1.87, 1.49, and 1.39, respectively. Graft loss analyses showed that those lost to biliary related complications were significantly higher in the DCD group even 3 years after LT. National registry data demonstrate the protracted higher risks inherent to DCD liver grafts in comparison to their DBD counterparts, despite survival through the early period after LT. These findings underscore the importance of judicious DCD graft selection at individual center level to minimize the risk of long-term biliary complications.

The role of lymph node dissection and a new N-staging system for intrahepatic cholangiocarcinoma: a study from the SEER database

BACKGROUND

Although the National Comprehensive Cancer Network guidelines recommend routine lymph node dissection (LND) in intrahepatic cholangiocarcinoma (ICC), the role of LND remains controversial, and the node (N) stage is oversimplified.

METHODS

Patients were identified from the Surveillance, Epidemiology, and End Results research data 18 (SEER 18). Propensity score matching (PSM) was used to reduce bias, and Kaplan-Meier curves and Cox proportional hazards models were used to compare overall survival (OS). The best cutoff values were found using X-tile software.

RESULTS

Of 2037 patients included in SEER 18, 1147 underwent LND (56.3%); 389 (34.3%) had pathologically confirmed lymph node metastasis (LNM), and 316 (27.6%) had at least 6 LNDs. The median OS was worse for LND patients (34 months vs. 40 months, respectively), and this result remained after PSM. Male sex, age ≥60 years, tumor size > 5 cm, and LNM were independent prognostic risk factors for ICC. LNM ≥3 was associated with worse OS.

CONCLUSIONS

Only a few LNDs met the requirements per the guidelines. LND does not improve OS in ICC, and the best approach to LND and a better N staging method should be explored further.

Recurrence of Non-functional Pancreatic Neuroendocrine Tumors After Curative Resection: A Tumor Burden-Based Prediction Model

BACKGROUND

Patients can experience recurrence following curative-intent resection of non-functional pancreatic neuroendocrine tumors (NF-pNETs). We sought to develop a nomogram to risk stratify patients relative to recurrence following resection of NF-pNETs.

METHODS

Patients who underwent curative-intent resection for NF-pNETs between 1997 and 2016 were identified from a multi-institutional database. The impact of clinicopathologic factors, including tumor burden score (TBS) (TBS² = (maximum tumor diameter)² + (number of tumors)²), was assessed relative to recurrence-free survival (RFS), and a nomogram was developed and internally validated.

RESULTS

With a median follow-up of 31.0 months (IQR 11.3-56.6 months), 66 (15.8%) out of 416 patients in the cohort experienced tumor recurrence. Overall, 3-, 5-, and 10-year RFS following curative-intent resection was 83.2%, 74.0%, and 44.7%, respectively. Several factors were associated with risk of recurrence including tumor grade (referent G1: G2, HR 4.07, 95% CI 2.29-7.26, p < 0.001; G3, HR 10.83, 95% CI 3.72-31.53, p < 0.001), lymph node metastasis (LNM) (HR 4.71, 95% CI 2.69-8.26, p < 0.001), as well as TBS (referent low: medium, HR 4.36, 95% CI 2.06-9.24, p < 0.001; high, HR 6.04, 95% CI 2.96-12.31, p < 0.001). A weighted nomogram including tumor grade (G1 0, G2 54.19, G3 100), LNM (N0 0, N1 42.06), and TBS (low 0, medium 44.07, high 56.48) was developed. The discriminatory power of the nomogram was very good with a C-index of 0.75 (95% CI, 0.66-0.79) in the training cohort and 0.71 (95% CI, 0.65-0.75) in the validation cohort. In addition, the nomogram performed better than the current 8th edition of AJCC TNM staging system, which had a C-index of 0.67 (95% CI, 0.60-0.73).

CONCLUSIONS

A nomogram that incorporated tumor grade, LNM, and TBS was established that had good discrimination and calibration. The nomogram may be an effective tool to stratify patients relative to recurrence risk following resection of NF-pNETs.

Comparative performances of nomograms and conditional survival after resection of adrenocortical cancer

Background

Adrenocortical carcinomas (ACCs) carry a poor prognosis. This study assessed the comparative performance of existing nomograms in estimating the likelihood of survival, along with the value of conditional survival estimation for patients who had already survived for a given length of time after surgery.

Methods

This was an observational study based on a prospectively developed departmental database that recorded details of patients operated for ACC in a UK tertiary referral centre.

Results

Of 74 patients with ACC managed between 2001 and 2020, data were analysed for 62 patients (32 women and 30 men, mean(s.d.) age 51(17) years) who had primary surgical treatment in this unit. Laparoscopic (9) or open adrenalectomies (53) were performed alone or in association with a multivisceral resection (27). Most of the tumours were left-sided (40) and 18 were cortisol-secreting.

Overall median survival was 33 months, with 1-, 3- and 5-year survival rates of 79, 49, and 41 per cent respectively. Age over 55 years, higher European Network for Study of Adrenal Tumours stage, and cortisol secretion were associated with poorer survival in univariable analyses. Four published nomograms suggested widely variable outcomes that did not correlate with observed overall survival at 1, 3 or 5 years after operation. The 3-year conditional survival at 2 years (probability of surviving to postoperative year 5) was 65 per cent, compared with a 5-year actuarial survival rate of 41 per cent calculated from the time of surgery.

Conclusion

Survival of patients with ACC correlates with clinical parameters but not with published nomograms. Conditional survival might provide a more accurate estimate of survival for patients who have already survived for a certain amount of time after resection.

Currently available treatment options for neuroendocrine liver metastases

Neuroendocrine neoplasms (NEN) are frequently characterized by a high propensity for metastasis to the liver, which appears to be a dominant site of distant-stage disease, affecting quality of life and overall survival. Liver surgery with the intention to cure is the treatment of choice for resectable neuroendocrine liver metastases (NELM), aiming to potentially prolong survival and ameliorate hormonal symptoms refractory to medical control. Surgical resection is indicated for patients with NELM from well-differentiated NEN, while its feasibility and complexity are largely dictated by the degree of liver involvement. As a result of advances in surgical techniques over the past decades, complex 1- and 2-stage, or repeat liver resections are performed safely and effectively by experienced surgeons. Furthermore, liver transplantation for the treatment of NELM should be anchored in a multimodal and multidisciplinary therapeutic strategy and restricted only to highly selected individual cases. A broad spectrum of interventional radiology treatments for NELM have recently been available, with expanding indications that are more applicable, as they are less limited by patient- and tumor-related parameters, being therefore important adjuncts or alternatives to surgery. Overall, liver-targeted treatment modalities may precede the administration of systemic molecular targeted agents and chemotherapy for patients with liver-dominant metastatic disease; these appear to be a crucial component of multimodal management of patients with NEN. In the present review, we discuss surgical and non-surgical liver-targeted treatment approaches for NELM, each complementing the other, with a view to assisting physicians in optimizing multimodal NEN patient care.

Defining and Predicting Early Recurrence after Resection for Gallbladder Cancer

BACKGROUND

The optimal time interval to define early recurrence (ER) among patients who underwent resection of gallbladder cancer (GBC) is not well defined. We sought to develop and validate a novel GBC recurrence risk (GBRR) score to predict ER among patients undergoing resection for GBC.

PATIENTS AND METHODS

Patients who underwent curative-intent resection for GBC between 2000 and 2018 were identified from the US Extrahepatic Biliary Malignancy Consortium database. A minimum p value approach in the log-rank test was used to define the optimal cutoff for ER. A risk stratification model was developed to predict ER based on relevant clinicopathological factors and was externally validated.

RESULTS

Among 309 patients, 103 patients (33.3%) had a recurrence at a median follow-up period of 15.1 months. The optimal cutoff for ER was defined at 12 months (p = 3.04 × 10^-18). On multivariable analysis, T3/T4 disease (HR: 2.80; 95% CI 1.58-5.11) and poor tumor differentiation (HR: 1.91; 95% CI 1.11-3.25) were associated with greater hazards of ER. The GBRR score was developed using β-coefficients of variables in the final model, and patients were classified into three distinct groups relative to the risk for ER (12-month RFS; low risk: 88.4%, intermediate risk: 77.9%, high risk: 37.0%, p < 0.001). The external validation demonstrated good model generalizability with good calibration (n = 102: 12-month RFS; low risk: 94.2%, intermediate risk: 59.8%, high risk: 42.0%, p < 0.001). The GBRR score is available online at https://ktsahara.shinyapps.io/GBC_earlyrec/ .

CONCLUSIONS

A novel online calculator was developed to help clinicians predict the probability of ER after curative-intent resection for GBC. The proposed web-based tool may help in the optimization of surveillance intervals and the counselling of patients about their prognosis.

Cholangiocarcinoma: investigations into pathway-targeted therapies

INTRODUCTION

Cholangiocarcinoma is a malignant disease of the biliary tract and accounts for 3% of all gastrointestinal tumors. Surgical intervention is currently the only potentially curative strategy for cholangiocarcinoma. For patients with unresectable, advanced or metastatic disease, the combination of gemcitabine with cisplatin is considered the standard treatment. However, currently available therapeutic options have only a marginal benefit, especially among patients with relapsed/refractory tumors.

AREAS COVERED

We reviewed targeted agents under clinical evaluation for patients with cholangiocarcinoma. FGFR and IDH inhibitors are at the most advanced stage of clinical investigation. EGFR inhibitors have demonstrated contradictory results, whereas inhibition of other molecular pathways, including the RAS/RAF/MEK/ERK, the MET, the PI3K/AKT/mTOR and angiogenetic pathways, has shown minimal or null benefit.

EXPERT OPINION

Several targeted approaches are being investigated for advanced cholangiocarcinoma. However, randomized clinical trials are needed to define the optimal treatment regimen and address issues including the option of monotherapy or combination regimens, the optimal sequence of different treatments, ways to overcome resistance to targeted treatments, as well as determining the right time and tissue for assessing molecular signatures. Targeted therapies and immunotherapy hold promise for improving patient outcomes in the future.