[Metastasis of medullary thyroid carcinoma to the endometrium: A case report and review of the literature]. / Metástasis de carcinoma medular de tiroides en endometrio: reporte de un caso y revisión de la literatura.

Uterine metastases from extra pelvic tumors are rare; involvement of the uterus is usually by direct neoplastic extension from adjacent organs. We report the case of a 68-year-old woman with a history of total thyroidectomy. She presented with urinary incontinence associated with episodes of metrorrhagia. Ultrasound showed a thickened endometrium. A legrado was performed and the biopsy revealed a proliferation of neoplastic cells with oval nuclei, «salt and pepper¼ chromatin, evident nucleoli and a moderate amount of eosinophilic cytoplasm. These cells were positive for CKAE1 / AE3, TTF-1, CEA and calcitonin. The histological and immunohistochemical findings corresponded to a metástasis from a medullary thyroid carcinoma. Although metastatic tumors in the uterus are extremely rare, they may give rise to abnormal uterine bleeding and should be considered when the patient's history and the histological findings are not characteristic of a primary lesion.

Systematic review of neuroendocrine carcinomas of the oropharynx.

Data describing features and management of oropharyngeal neuroendocrine carcinomas (NEC) remain sparse. A systematic review was performed. Patients were stratified by treatment modality and examined for disease progression and survival outcomes. Ninety-four patients from 50 publications were included. Average age at diagnosis was 59.7 years (range 14-83). 73.4% were male. Most studies did not document HPV status. Forty patients (85.1%) were p16 positive, and 34 (85.0%) were HPV-ISH positive. Overall survival was 75.4% at 1 year, and 40.0% at 2 years. Of patients with locoregional disease, 33.8% developed distant metastasis. 12.5% of patients developed locoregional recurrence. Patients who developed distant metastases had worse overall survival (p = 0.0004). No significant difference was found between treatment modalities. Human papilloma virus may be associated with oropharyngeal NEC. Current treatments provide locoregional control, but distant metastases are common and confer low overall survival.

Metastatic Patterns of Duodenopancreatic Neuroendocrine Tumors in Patients With Multiple Endocrine Neoplasia Type 1.

Patients with multiple endocrine neoplasia 1 syndrome (MEN1) often develop multifocal duodenopancreatic neuroendocrine tumors (dpNETs). Nonfunctional pancreatic neuroendocrine tumors (PanNETs) and duodenal gastrinomas are the most frequent origins of metastasis. Current guidelines recommend surgery based on tumor functionality, size ≥2 cm, grade or presence of lymph node metastases. However, in case of multiple primary tumors it is often unknown which specific tumor metastasized. This study aims to unravel the relationship between primary dpNETs and metastases in patients with MEN1 by studying endocrine differentiation. First, it was shown that expression of the endocrine differentiation markers ARX and PDX1 was concordant in 18 unifocal sporadic neuroendocrine tumors (NETs) and matched metastases. Thereafter, ARX, PDX1, Ki67 and gastrin expression, and the presence of alternative lengthening of telomeres were determined in 137 microscopic and macroscopic dpNETs and 36 matched metastases in 10 patients with MEN1. ARX and PDX1 H-score clustering was performed to infer relatedness. For patients with multiple metastases, similar intrametastases transcription factor expression suggests that most metastases (29/32) originated from a single NET of origin, while few patients may have multiple metastatic primary NETs. In 6 patients with MEN1 and hypergastrinemia, periduodenopancreatic lymph node metastases expressed gastrin, and clustered with minute duodenal gastrinomas, not with larger PanNETs. PanNET metastases often clustered with high grade or alternative lengthening of telomeres-positive primary tumors. In conclusion, for patients with MEN1-related hypergastrinemia and PanNETs, a duodenal origin of periduodenopancreatic lymph node metastases should be considered, even when current conventional and functional imaging studies do not reveal duodenal tumors preoperatively.

Spinal metastases from thyroid cancer: Some prognostic factors.

BACKGROUND: Spinal metastases (SpMs) from thyroid cancers (TC) significantly reduce quality of life by causing pain, neurological deficits in addition to increasing mortality. Moreover, prognosis factors including surgery remain debated. METHODS: Data were stored in a prospective French national multicenter database of patients treated for SpM between January 2014 and 2017. Fifty-one consecutive patients affected by TC with 173 secondary SpM were included. RESULTS: Mean overall survival (OS) time for all patients from the diagnosis of a thyroid SpM event was 9.1 years (SD 8.7 months). The 1-year, 5-year and 10-year survival estimates were 94% (SD 3.3), 83.8.0% (SD 5.2), and 74.5% (SD 9.9). The median period of time between primary thyroid tumor diagnosis and the SpM event was 31.4 months (SD 71.6). In univariate analysis, good ECOG-PS (status 0 and 1) (p < 0.0001), ambulatory status (Frankel score) (p < 0.0001) and no epidural involvement (p = 0.01), were associated with longer survival, whereas cancer subtype (p = 0.436) and spine surgery showed no association (p = 0.937). Cox multivariate proportional hazard model only identified good ECOG-PS: 0 [HR: 0.3, 95% CI 0.1-0.941; p < 0.0001], 1 [HR: 0.8, 95% CI 0.04-2.124; p = 0.001] and ambulatory neurological status: Frankel E [HR: 0.262, 95% CI 0.048-1.443; p = 0.02] to be independent predictors of better survival. CONCLUSION: For cases presenting SpM from TC, we highlighted that the only prognostic factors were the progression of the cancer (ECOG-PS) and the clinical neurological impact of the SpM (Frankel status). Surgery should be discussed mainly for stabilization and neurological decompression.

Scalp metastasis as initial presentation of neuroendocrine carcinoma.

Neuroendocrine carcinomas are a rare, heterogenous group of malignancies that arise from neuroendocrine cells throughout the body. Cutaneous metastasis of neuroendocrine carcinoma is uncommon and they can be easily misdiagnosed as benign epidermal cysts or Merkel cell carcinoma. Collectively, histopathology, immunochemical profile, biochemical markers, and nuclear imaging can guide the diagnosis of neuroendocrine metastasis and localization of primary tumors.

Pituitary Metastasis of Lung Neuroendocrine Carcinoma Mimicking Pituitary Adenoma:Case Report and Literature Review.

Pituitary metastasis is an unusual situation in clinical practice, while the incidence is increasing with age. Breast cancer for women and lung cancer for men were the most frequent primary origins of pituitary metastasis. Diagnosing asymptomatic patients with unknown primary malignant origin is difficult, thus pituitary metastasis may be diagnosed as primary pituitary adenoma. Here, we report a case of a 65-year-old patient with visual changes and diabetes insipidus, showing an extensive mass in the sellar region which was initially thought to be a primary pituitary adenoma. Patient corticotropic deficits were corrected, and transnasal transsphenoidal surgery was adopted, leading to total tumor resection. Tumor texture during surgical procedure was similar to that of pituitary adenoma. However, the histopathological and immunohistochemistry results suggested it as a pituitary metastasis from lung neuroendocrine tumor. Postoperative chest CT scan confirmed a pulmonary mass consistent with primary neoplasm. Abdominal CT further detected multiple metastases in liver, pancreas, and colon. Despite intensive treatment, the patient continued to show decreased level of consciousness due to cachexia, resulting in death 1 week after surgery. This case highlights the importance of differential diagnosis of invasive lesions of the sellar region, especially in individuals over 60 years of age with diabetes insipidus.

Metastatic Medullary Thyroid Cancer: The Role of 68Gallium-DOTA-Somatostatin Analogue PET/CT and Peptide Receptor Radionuclide Therapy.

CONTEXT: Metastatic medullary thyroid cancer (MTC) is a rare malignancy with minimal treatment options. Many, but not all, MTCs express somatostatin receptors. OBJECTIVE: Our aim was to explore the role of 68Ga-DOTA-somatostatin analogue (SSA) positron emission tomography (PET)/computed tomography (CT) in patients with metastatic MTC and to determine their eligibility for peptide receptor radionuclide therapy (PRRT). METHODS: We retrospectively identified patients with metastatic MTC who had 68Ga-DOTA-SSA PET/CT at 5 centers. We collected characteristics on contrast-enhanced CT, 68Ga-DOTA-SSA and 18F-FDG PET/CT. The efficacy of PRRT was explored in a subgroup of patients. Kaplan-Meier analysis was used to estimate time to treatment failure (TTF) and overall survival (OS). RESULTS: Seventy-one patients were included (10 local recurrence, 61 distant disease). Of the patients with distant disease, 16 (26%) had ≥50% of disease sites with tracer avidity greater than background liver, including 10 (10/61, 16%) with >90%. In 19 patients with contemporaneous contrast-enhanced CT, no disease regions were independently identified on 68Ga-DOTA-SSA PET/CT. Thirty-five patients had an 18F-FDG PET/CT, with 18F-FDG positive/68Ga-DOTA-SSA negative metastases identified in 15 (43%). Twenty-one patients had PRRT with a median TTF of 14 months (95% CI 8-25) and a median OS of 63 months (95% CI 21-not reached). Of the entire cohort, the median OS was 323 months (95% CI 152-not reached). Predictors of poorer OS included a short calcitonin doubling-time (≤24 months), strong 18F-FDG avidity, and age ≥60 years. CONCLUSIONS: The prevalence of high tumor avidity on 68Ga-DOTA-SSA PET/CT is low in the setting of metastatic MTC; nevertheless, PRRT may still be a viable treatment option in select patients.

Neuroendocrine carcinoma of prostate presenting with ascites.

Prostate cancer is a very common cause of morbidity and mortality in India. The commonest type of prostate carcinoma is adenocarcinoma, most of them are confined to prostate at the time of presentation. Bone is the preferred site for metastasis. The following is a case of neuroendocrine carcinoma of prostate arising in a 36 years old male who presented with ascitis and jaundice to the emergency department. The ascitic tap was positive for malignant cells. CECT done to detect primary showed osteoblastic secondaries in the spine along with lesions in the liver. DRE revealed grade 2 prostatomegaly. A TRUS guided biopsy showed neuroendocrine carcinoma of the prostate. Neuroendocrine carcinoma is a very rare type of prostatic carcinoma, with presentation of the same as ascitis is very uncommon. The following case is presented due to its rarity.

PD-L1, PARP1, and MMRs as potential therapeutic biomarkers for neuroendocrine cervical cancer.

OBJECTIVE: Neuroendocrine cervical cancer (NECC) is a rare cervical cancer with high aggressivity that causes poor prognosis even in the early stage. Given other neuroendocrine carcinomas and other types of cervical cancer have been proved to have expression of programmed cell death protein 1 ligand 1(PD-L1) and poly ADP-ribose polymerase-1(PARP1), we would measure and analyze these proteins in this invasive cancer. The purpose of this study is to investigate the application value of PD-1/PD-L1 and PARP1 inhibitors in NECC. METHODS: The NECC cases in our center with formalin-fixed paraffin-embedded tissue blocks were collected, and immunohistochemical (IHC) staining of PD-L1, PARP1, Mismatch repair proteins (MMRs), and P53 was performed. Chi-square test was used to analyze associations between various protein expressions. We analyzed the efficacy of immunotherapy in a recent patient with secondary recurrence after two courses of chemotherapy. RESULTS: After rigorous screening, 20 cases were finally included. Three cases did not undergo surgical treatment because of their advanced stage. Twelve (60%) developed distant metastases or relapsed within five years, and most of them within two years. The positive rate of PD-L1 and PARP1 were 70% and 75% respectively. Among all the cases, microsatellite instability (MSI) was seen in six cases (30%) and abnormal p53 expression was in 15 patients (75%). PD-L1 was associated with PARP1 expression in the MSI subgroup. The patient treated with chemotherapy + VEGF inhibitor (VEGFi) + programmed cell death protein 1(PD-1) inhibitor had an excellent improvement in clinical symptoms, tumor markers, and mass size. CONCLUSION: The IHC results of PD-L1, PARP1, and MMRs suggested that NECC was the target of immunotargeted therapy. Our case confirmed that immune checkpoint therapy was effective in patients with PD-L1 positive and MMRs loss. Considering the clinical practicability, more cases should be collected, and effective biomarkers still need to be further searched.

Establishment and characterization of a novel treatment-related neuroendocrine prostate cancer cell line KUCaP13.

The prevalence of neuroendocrine prostate cancer (NEPC) arising from adenocarcinoma (AC) upon potent androgen receptor (AR) pathway inhibition is increasing. Deeper understanding of NEPC biology and development of novel therapeutic agents are needed. However, research is hindered by the paucity of research models, especially cell lines developed from NEPC patients. We established a novel NEPC cell line, KUCaP13, from tissue of a patient initially diagnosed with AC which later recurred as NEPC. The cell line has been maintained permanently in vitro under regular cell culture conditions and is amenable to gene engineering with lentivirus. KUCaP13 cells lack the expression of AR and overexpress NEPC-associated genes, including SOX2, EZH2, AURKA, PEG10, POU3F2, ENO2, and FOXA2. Importantly, the cell line maintains the homozygous deletion of CHD1, which was confirmed in the primary AC of the index patient. Loss of heterozygosity of TP53 and PTEN, and an allelic loss of RB1 with a transcriptomic signature compatible with Rb pathway aberration were revealed. Knockdown of PEG10 using shRNA significantly suppressed growth in vivo. Introduction of luciferase allowed serial monitoring of cells implanted orthotopically or in the renal subcapsule. Although H3K27me was reduced by EZH2 inhibition, reversion to AC was not observed. KUCaP13 is the first patient-derived, treatment-related NEPC cell line with triple loss of tumor suppressors critical for NEPC development through lineage plasticity. It could be valuable in research to deepen the understanding of NEPC.

Efficacy and safety of peptide receptor radionuclide therapy in advanced radioiodine-refractory differentiated thyroid cancer and metastatic medullary thyroid cancer: a systematic review.

BACKGROUND: It has been shown that a subgroup of patients with differentiated thyroid cancer (DTC) and medullary thyroid carcinoma (MTC) would progress to advanced stages of thyroid cancer. Therefore, the present study was done to systematically review available evidence in order to investigate efficacy and safety of peptide receptor radionuclide therapy (PRRT) in the patients with advanced radioiodine refractory differentiated thyroid cancer (RR-DTC) and metastatic MTC. METHODS: For this purpose, relevant studies investigated safety and efficacy of PRRT in the patients with advanced RR-DTC and metastatic MTC were identified by searching Medline (Pubmed, Ovid, and Ebsco), Scopus, Embase, Web of Science, and Cochrane Library databases (from database inception to March 24, 2021). The review was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. Searching was done independently by two investigators. Two researchers independently extracted the data and any disagreement was adjudicated by consensus. Quality of the studies was assessed using the tool of case reports/series in systematic reviews. RESULTS: Among 2284 related papers, 41 papers met the inclusion criteria. A total of 157 patients with RR-DTC were treated with PPRT. Biochemical and objective responses (partial and complete) were observed in 25.3 and 10.5% of patients, respectively. Among 220 patients with metastatic MTC, biochemical and objective responses were observed in 37.2 and 10.6% of the patients, respectively. Forty-six deaths were reported in 95 patients with advanced RR-DTC. In addition, 63 deaths were observed in 144 patients with metastatic MTC. Major side effects were reported in 124 patients treated with 90Y -based agent. In the patients treated with 177Lu-DOTA-TATE and 111In-Octreotide, mild and transient hematologic or renal complications were reported. CONCLUSION: Findings of the study revealed that in the absence of the established treatment for the patients with RR-DTC and metastatic MTC, PRRT could be effective with few adverse events. TRIAL REGISTRATION: PROSPERO registration number: CRD42019125245 .

Clinicopathologic features of metastatic small cell carcinoma of the prostate to the liver: a series of four cases.

BACKGROUND: Small cell neuroendocrine carcinoma of the prostate (SCNECP) is a rare, aggressive subtype of prostate carcinoma. Most SCNECP arise from conventional prostate adenocarcinoma (CPAC) treated with androgen deprivation therapy (ADT). CASE PRESENTATIONS: We identified four cases of CPAC treated with ADT, which evolved to SCNECP with liver metastasis. The average interval between the diagnosis of CPAC and SCNECP was 102 months (range: 12 to 168). Histologically, the tumors showed nests of cells with high nuclear:cytoplasmic ratios, granular chromatin, and frequent mitoses. All cases were synaptophysin, chromogranin, and AE1/AE3 positive, with a Ki-67 labeling index ≥70%. NKX3.1 was negative in all but one case and TTF-1 was positive in half. Weak ERG positivity by IHC was seen in one case which also demonstrated the TMPRSS2-ERG gene rearrangement; all other cases were negative for ERG by IHC. Serum prostate specific antigen (PSA) levels were normal to near-normal in all. The median interval between the diagnosis of SCNECP and death was 3.25 months (range: 0.75 to 26). CONCLUSIONS: Our case series highlights the importance of considering a prostate primary, even in the setting of normal PSA levels and loss of prostate markers, when diagnosing neuroendocrine carcinoma in the liver. Further, we emphasize the significance of diagnosing SCNECP that metastasizes to the liver, as it portends a particularly dismal prognosis.

Real-world survival outcomes with immune checkpoint inhibitors in large-cell neuroendocrine tumors of lung.

BACKGROUND: Little is known regarding the efficacy of immune checkpoint inhibitors (ICI) in patients with advanced large-cell neuroendocrine lung carcinoma (aLCNEC). METHODS: 125 consecutive patients with aLCNEC were identified in the electronic databases of 4 participating cancer centers. The patients were divided into group A (patients who received ICI, n=41) and group B (patients who did not receive ICI, n=84). Overall survival since advanced disease diagnosis (OS DX) and OS since ICI initiation (OS ICI) were captured. RESULTS: With a median follow-up of 11.8 months (mo) (IQR 7.5-17.9) and 6.0mo (IQR 3.1-10.9), 66% and 76% of patients died in groups A and B, respectively. Median OS DX was 12.4mo (95% CI 10.7 to 23.4) and 6.0mo (95% CI 4.7 to 9.4) in groups A and B, respectively (log-rank test, p=0.02). For ICI administration, HR for OS DX was 0.59 (95% CI 0.38 to 0.93, p=0.02-unadjusted), and 0.58 (95% CI 0.34 to 0.98, p=0.04-adjusted for age, Eastern Cooperative Oncology Group (ECOG) performance status (PS), presence of liver metastases and chemotherapy administration). In a propensity score matching analysis (n=74; 37 patients in each group matched for age and ECOG PS), median OS DX was 12.5 mo (95% CI 10.6 to 25.2) and 8.4 mo (95% CI 5.4 to 16.9) in matched groups A and B, respectively (log-rank test, p=0.046). OS ICI for patients receiving ICI as monotherapy (n=36) was 11.0 mo (95% CI 6.1 to 19.4). CONCLUSIONS: With the limitations of retrospective design and small sample size, the results of this real-world cohort analysis suggest a positive impact of ICI on OS in aLCNEC.

Neuroendocrine Carcinoma of the Anus and Rectum: Patient Characteristics and Treatment Options.

INTRODUCTION: Anorectal neuroendocrine carcinomas (NECs) are uncommon malignancies with poor prognosis. Consensus guidelines exist for treating extrapulmonary NEC. However, limited data is available to guide treatment for anorectal NEC. In this study, we sought to review the clinical characteristics and outcomes of patients with NEC of the rectum and/or anus at Mayo Clinic. PATIENTS AND METHODS: This is a retrospective study of all patients with the diagnosis of NEC of the anus and/or rectum treated across Mayo Clinic sites since 2000. Baseline patient characteristics, tumor pathology, imaging profiles, treatment strategies utilized, and survival outcomes were analyzed. Kaplan-Meier analysis was used with a significance level of P < .05. RESULTS: The study included a total of 38 patients with primary NEC of the anus and/or rectum. The median age at diagnosis was 55.5 years. The median follow-up was 18.8 months. Fifteen patients had locoregional disease (LRD) at diagnosis. The remaining 23 had metastatic disease. Overall survival was significantly shorter in patients with LRD compared with those with metastatic disease at diagnosis (18.1 vs. 13.8 months; P = .039). The majority (n = 11) of patients with LRD were treated with concurrent chemoradiation therapy, and 10 underwent surgical resection of the primary tumor. The majority (13/15) of patients with LRD progressed, with the majority (11/15) of progressions being distant. The median progression-free survival for patients with LRD was 5.7 months (1-year progression-free survival, 26.7%). CONCLUSION: Anorectal NEC is an aggressive malignancy with poor prognosis requiring multidisciplinary discussion. In addition, the systemic nature of anorectal NEC with distant recurrences in LRD and poor outcomes in metastatic disease emphasizes the need to further develop better systemic treatment options that can potentially improve outcomes in NEC.

Correlation between Ultrasonic Features of Medullary Thyroid Carcinoma and Cervical Lymph Node Metastasis.

The aim of this study was to investigate the factors that affect cervical lymph node metastasis (CLNM) in individuals with medullary thyroid carcinoma (MTC) in terms of ultrasonic characteristics and other parameters. Single-factor χ2 analysis showed that the ultrasonic characteristics of tumor size >10 mm, unclear boundary, irregular pattern and capsular invasion, as well as pre-operative calcitonin level >302.50 pg/mL (p < 0.001) and age ≤52.50 y (p = 0.036), were risk factors for CLNM in individuals with MTC. Multivariate logistic regression analysis showed that age ≤52.50 y (odds ratio = 3.796; 95% confidence interval, 1.010-14.259; p = 0.048), irregular pattern (odds ratio = 5.262; 95% confidence interval, 1.200-23.084; p = 0.028) and tumor size >10 mm (odds ratio = 7.789; 95% confidence interval, 1.123-54.005; p = 0.038) were independent risk factors for CLNM in individuals with MTC. Individuals with MTC aged ≤52.50 y with an irregular pattern and tumor size >10 mm were more likely to develop CLNM. In addition, those with a pre-operative calcitonin level >302.50 pg/mL were more likely to have CLNM.

Primary MiNEN of the urinary bladder: an hitherto undescribed entity composed of large cell neuroendocrine carcinoma and adenocarcinoma with a distinct clinical behavior : Description of a case and review of the pertinent literature.

Neuroendocrine carcinomas (NECs) of the urinary bladder are very rare and can be observed in the context of mixed neuroendocrine/non-neuroendocrine neoplasms (MiNENs), most frequently in association with urothelial carcinoma. Small cell NECs are far more common than large cell NECs (LCNECs), which are exceedingly rare. We describe a primary MiNEN of the urinary bladder, composed of a LCNEC and of an adenocarcinoma, in which the neuroendocrine component reached complete pathological regression after neoadjuvant M-VAC chemotherapy, whereas the non-neuroendocrine component of the tumor progressed to metastatic disease. Compared to mixed neuroendocrine/non-neuroendocrine neoplasms described in the literature until now, this appears to be a unique case that expands the spectrum of neuroendocrine neoplasia of the urinary bladder.

Expression and clinical significance of a new neuroendocrine marker secretagogin in cervical neuroendocrine carcinoma.

AIMS: To explore the expression of secretagogin (SCGN) in neuroendocrine carcinoma of the uterine cervix and analyse its relationship with clinicopathological characteristics and prognosis. METHODS: From January 2010 to December 2017, 44 patients with cervical neuroendocrine carcinoma undergoing surgery were included in the study group, and 55 patients with cervical non-neuroendocrine carcinoma (including 30 cases of cervical squamous cell carcinoma and 25 cases of cervical adenocarcinoma) undergoing surgery were included in the control group. Immunohistochemical staining of SCGN was performed in both groups and compared with three common neuroendocrine markers, chromogranin A, synaptophysin (Syn) and CD56 in the study group. Detailed clinicopathological data of the two groups were analysed, and the patient survival in the study group was followed up. RESULTS: The positive expression of SCGN in cervical neuroendocrine carcinoma, cervical adenocarcinoma and squamous cell carcinoma was 65.9% (29/44), 8% (2/25) and 0%, respectively. The positive expression of SCGN in cervical neuroendocrine carcinoma was significantly higher than that in cervical adenocarcinoma and squamous cell carcinoma (χ2=44.5, p<0.001). There were no statistical differences among the positive expression of SCGN and three common neuroendocrine markers (p>0.05 for all). The intensity of SCGN staining in patients with cervical neuroendocrine carcinoma with lymph node metastasis was significantly higher than that in patients without lymph node metastasis (p=0.020). However, there was no significant association between SCGN expression and survival among patients with cervical neuroendocrine carcinoma (p=0.633). CONCLUSIONS: SCGN is a new neuroendocrine marker for cervical neuroendocrine carcinoma, whose expression correlates with lymph node metastasis.

A Comparison of Liver-Directed Therapy and Systemic Therapy for the Treatment of Liver Metastases in Patients with Gastrointestinal Neuroendocrine Tumors: Analysis of the California Cancer Registry.

PURPOSE: To compare the outcomes of patients with gastrointestinal neuroendocrine tumor liver metastases treated with liver-directed therapy (LDT) to those treated with systemic therapy (ST) in a statewide cancer database. MATERIALS AND METHODS: A retrospective study was performed of patients with metastatic gastrointestinal tract neuroendocrine tumors treated with either LDT or ST alone between the years 2000-2012 in the California Cancer Registry. Overall survival and disease-specific survival were assessed using multivariable Cox proportional hazards analysis and propensity score matching. RESULTS: A total of 154 patients (ST, n = 87 and LDT, n = 67) were studied. The median overall survival and disease-specific survival for patients that received ST was 29 and 35 months versus 51 and >60 months for patients that received LDT. On multivariate analysis, LDT and the resection of the primary tumor were associated with improved survival (hazard ratio [HR] 0.52, P = .002; HR 0.43, P = .001). Non-white race, Medicaid/uninsured status, and the presence of lung metastases were associated with poor survival (HR 1.76, P = .014; HR 2.29, P = .009; and HR 1.79, P = .031). Propensity score matching demonstrated an improvement in disease-specific survival for LDT compared to ST (HR 0.53, P = .036). The improvement in overall survival on propensity score matching did not achieve statistical significance (HR 0.70, P = .199). CONCLUSIONS: LDT is associated with improved overall and disease-specific survival as compared to ST in patients with gastrointestinal neuroendocrine tumor liver metastases. Further investigation is needed to determine whether combination or sequential treatment can improve outcomes in this population.