Liver-Directed Therapies for Neuroendocrine Neoplasms

Exploring Carcinoid Syndrome in Neuroendocrine Tumors: Insights from a Multidisciplinary Narrative Review

Carcinoid syndrome (CS) is a rare condition associated with neuroendocrine tumors (NETs), particularly those originating in the gastrointestinal tract, which secrete bioactive substances like serotonin. The management of CS requires a multidisciplinary approach due to its complex clinical manifestations, including flushing, diarrhea, bronchospasm, and carcinoid heart disease. Optimal care involves collaboration between several professional figures like oncologists, endocrinologists, gastroenterologists, surgeons, and dietitians. Currently, a wide range of treatments are available, focused on both symptom control and tumor burden reduction. Somatostatin analogs (SSAs) are the first-line therapy for symptom relief. Still, in patients with progressive disease or refractory CS, other options include targeted therapies, peptide receptor radionuclide therapy (PRRT), liver-directed therapies, and surgical resection, when feasible. Furthermore, management of complications related to prolonged serotonin release and malnutrition as a result of exocrine pancreatic insufficiency, post-surgical conditions, vitamin deficit, and chronic diarrhea often requires early detection to mitigate symptoms and improve the quality of life in these patients. The complexity of CS necessitates individualized care and continuous coordination among specialists to optimize outcomes and enhance patient well-being.

Liver metastases of neuroendocrine tumors: Conventional transarterial chemoembolization and thermal ablation

PURPOSE

To identify prognostic factors for patients with neuroendocrine liver metastases (NELM) undergoing conventional transarterial chemoembolization (c-TACE), microwave ablation (MWA), or laser interstitial thermotherapy (LITT) and to determine the most effective therapy regarding volume reduction of NELM and survival.

MATERIALS AND METHODS

Between 1996 and 2020, 130 patients (82 men, 48 women) were treated with c-TACE, and 40 patients were additionally treated with thermal ablation. Survival was retrospectively analyzed using the Kaplan-Meier-method. Additional analyses were performed depending on the therapeutic intention (curative, palliative, symptomatic). Prognostic factors were derived using Cox regression. To find predictive factors for volume reduction in response to c-TACE, a mixed-effects model was used.

RESULTS

With c-TACE, an overall median volume reduction of 23.5 % was achieved. An average decrease in tumor volume was shown until the 6th c-TACE treatment, then the effect stopped. C-TACE interventions were most effective at the beginning of c-TACE therapy, and treatment breaks longer than 90 days negatively influenced the outcome. Significant prognostic factors for survival were number of liver lesions (p = 0.0001) and type of therapeutic intention (p < 0.0001). Minor complications and one major complication occurred in 20.3 % of LITT and only in 8.6 % of MWA interventions. Complete ablation was observed in 95.7 % (LITT) and 93.1 % (MWA) of interventions.

CONCLUSION

New prognostic factors were found for survival and volume reduction. Efficacy of c-TACE decreases after the 6th intervention and treatment breaks longer than 90 days should be avoided. With thermal ablation, a high rate of complete ablation was achieved, and survival improved.

KEY POINTS

· Number of liver lesions and therapeutic intention are prognostic factors for survival.. · Regarding volume reduction, C-TACE is most effective at the beginning of treatment and longer treatment breaks should be avoided.. · With MWA and LITT, a high rate of complete ablation was achieved. MWA trends toward fewer complications than LITT in the treatment of NELM (p = 0.07)..

Therapeutic Challenges for Gastric Neuroendocrine Neoplasms: Take It or Leave It?

Background and Objectives: Gastric neuroendocrine neoplasms (gNENs) represent rare but increasingly recognized tumors. They are distinguished into three main clinical types (type-1, type-2, and type-3) according to gastrin level and at histological evaluation in well-differentiated G1, G2, or G3 lesions, as well as poorly-differentiated lesions. Small type-1 and type-2 neoplasms with low proliferation indices demonstrated excellent survival without progression during an extended follow-up period, and for these reasons, active endoscopic observation or endoscopic resection are feasible options. On the other hand, surgery is the treatment of choice for more aggressive type-3, G3, or infiltrating neoplasms. The present study aims to comprehensively review and compare the available therapeutic strategies for gNENs. Materials and Methods: A computerized literature search was performed using relevant keywords to identify all of the pertinent articles with particular attention to gNEN endoscopic treatment. Results: In recent years, different endoscopic resective techniques (such as endoscopic mucosal dissection, modified endoscopic mucosal resection, and endoscopic full-thickness resection) have been developed, showing a high rate of complete resection for advanced and more aggressive lesions. Conclusions: Overall, gNENs represent a heterogeneous group of lesions with varying behavior which require personalized management. The non-operative approach for small type-1 gNENs seems to be feasible and should be promoted. A step-up approach with minimally invasive endoscopic therapies might be proposed, particularly for type-1 gNEN. On the other hand, it is important to recognize the negative prognostic factors in order to identify those rare cases requiring more aggressive approaches. A possible therapeutic algorithm for localized gNEN management is provided.

Efficacy of selective transarterial chemoembolization for recurred liver metastases from intracranial meningioma: A case report

Extracranial metastases from intracranial meningioma involve multiple organs with repeatedly recurrence. Due to the rarity of these metastases, management remains to be established, especially in cases that are not amenable to surgery, such as postsurgical relapse and multiple metastases. We present the case of a right tentorial meningioma with multiple extracranial metastases, including postsurgical recurrent liver metastases. The intracranial meningioma was surgically resected when the patient was 53 years of age. The patient was 66 years of age when the hepatic lesion was first revealed, for which an extended right posterior sectionectomy was performed. Histopathology demonstrated a metastatic meningioma. Twelve months after liver resection, multiple local recurrences in the right hepatic lobe were revealed. Because additional surgical resection would put the patient at risk of declining residual liver function, we performed selective transarterial chemoembolization, resulting in a reduction in size and good control without relapse. Selective transarterial chemoembolization for incurable liver metastatic meningiomas could be valuable in palliating patients unsuitable for surgery.

Developments in interventional management of hepatic metastases from neuroendocrine tumours

Neuroendocrine tumours commonly metastasise to the liver, particularly those arising from the intestinal tract and pancreas. Whilst surgery offers the only approach with intent to cure, the vast majority of patients with neuroendocrine liver metastases are ineligible. Liver-directed interventional therapies seek to exploit the patho-anatomy of the blood supply of hepatic metastases to deliver therapy to liver deposits. This may involve percutaneous ablation, bland embolization, or the selective infusion of chemotherapeutics, targeted agents or radiolabelled embolic material. Retrospective case series evidence has characterised objective response rates, disease control rates, and longer-term outcomes associated with each approach. Recent advances in this field include ongoing comparative trials of different techniques, but more importantly, combinations of interventional liver-directed therapies and other systemic therapy in multimodal treatment concepts.

Primary neuroendocrine tumors and primary neuroendocrine carcinomas of the liver: a proposal for a multidiscipline definition

Primary hepatic neuroendocrine tumors and primary hepatic neuroendocrine carcinomas are rare and pose challenges for both diagnosis and for determining whether the tumor is primary to the liver versus metastatic disease. The lack of a uniform definition for primary hepatic neuroendocrine neoplasms is also a limitation to understanding and treating these rare tumors. Recently, there have been significant histological advances in the diagnosis and classification of neuroendocrine tumors in general, as well as significant advances in imaging for neuroendocrine neoplasms, all of which are important for their treatment. This article presents a multiple disciplinary definition and proposed guidelines for diagnosing a neuroendocrine tumor/neuroendocrine carcinomas as being primary to the liver.

Yttrium-90 Radioembolization for Liver-Dominant Metastatic Prostate Cancer: A Case Series

Transarterial radioembolization (TARE) with yttrium-90 glass microspheres is widely used to treat primary and secondary malignancies in the liver. However, the safety and efficacy of TARE in patients with liver-dominant metastatic castration-resistant prostate cancer (mCRPC) is unknown. A proof-of-concept, retrospective analysis of 7 consecutive patients with liver-dominant mCRPC who were treated with TARE was performed. The median overall survival was 27.2, 32.1, and 108.1 months from the time of TARE, the diagnosis of liver metastases, and initial cancer diagnosis, respectively. The median liver progression-free survival was 7.3 months. No grade 3 or higher adverse effects were noted. TARE was found to be a safe and effective tool for treating patients with liver-dominant mCRPC in this limited cohort.

Differenzierte Therapiestrategie bei Lebermetastasen gastro-entero-pankreatischer Neuroendokriner Neoplasien

Neuroendokrine Neoplasien (NEN) bilden eine heterogene Gruppe maligner Tumoren, die überwiegend dem gastro-entero-pankreatischen System (GEP) zuzuordnen sind. Hierbei sind Dünndarm und Pankreas die häufigsten Organe für Primärtumoren, die Leber stellt den dominanten Metastasierungsort dar. Da viele Patient*innen lange asymptomatisch bleiben, führen oftmals zufällig diagnostizierte Lebermetastasen oder ein Ileus zur Diagnose. Die einzige kurative Therapieoption stellt die komplette Entfernung von Primarius und Metastasen dar. Besonders im Falle der metastasierten Erkrankung sollten die vorhandenen Therapieoptionen immer im interdisziplinären Tumorboard mit Spezialisten*innen aus Gastroenterologie, (Leber-)Chirurgie, Radiologie, Nuklearmedizin, Radiotherapie, Pathologie und Endokrinologie evaluiert werden. Durch die Kombination der verschiedenen Therapieverfahren kann auch für Patient*innen mit fortgeschrittener Erkrankung eine jahrelange Prognose bei guter Lebensqualität erreicht werden. Wichtig für die Therapieentscheidung sind neben patientenindividuellen Faktoren der Differenzierungsgrad des Tumors, dessen hormonelle Sekretion, das Metastasierungsmuster und der Erkrankungsverlauf. Die Behandlung von Lebermetastasen umfasst neben den unterschiedlichen chirurgischen Strategien die lokal-ablativen radiologischen und nuklearmedizinischen Verfahren, die als Ergänzung zu den systemischen Therapien zur Verfügung stehen.

Predictive Factors for Resistant Disease with Medical/Radiologic/Liver-Directed Anti-Tumor Treatments in Patients with Advanced Pancreatic Neuroendocrine Neoplasms: Recent Advances and Controversies

Purpose: Recent advances in the diagnosis, management and nonsurgical treatment of patients with advanced pancreatic neuroendocrine neoplasms (panNENs) have led to an emerging need for sensitive and useful prognostic factors for predicting responses/survival. Areas covered: The predictive value of a number of reported prognostic factors including clinically-related factors (clinical/laboratory/imaging/treatment-related factors), pathological factors (histological/classification/grading), and molecular factors, on therapeutic outcomes of anti-tumor medical therapies with molecular targeting agents (everolimus/sunitinib/somatostatin analogues), chemotherapy, radiological therapy with peptide receptor radionuclide therapy, or liver-directed therapies (embolization/chemoembolization/radio-embolization (SIRTs)) are reviewed. Recent findings in each of these areas, as well as remaining controversies and uncertainties, are discussed in detail, particularly from the viewpoint of treatment sequencing. Conclusions: The recent increase in the number of available therapeutic agents for the nonsurgical treatment of patients with advanced panNENs have raised the importance of prognostic factors predictive for therapeutic outcomes of each treatment option. The establishment of sensitive and useful prognostic markers will have a significant impact on optimal treatment selection, as well as in tailoring the therapeutic sequence, and for maximizing the survival benefit of each individual patient. In the paper, the progress in this area, as well as the controversies/uncertainties, are reviewed.