Prognostic clinicopathologic factors in longitudinally followed patients with metastatic small bowel carcinoid tumors

Epidemiologic Trends of and Factors Associated With Overall Survival for Patients With Gastroenteropancreatic Neuroendocrine Tumors in the United States

IMPORTANCE

Although the incidence and prevalence of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) have been thought to have increased during the past decades, updated epidemiologic and survival data are lacking.

OBJECTIVES

To conduct an epidemiologic and survival analysis of the largest cohort of patients with GEP-NETs using the latest data and to establish a novel nomogram to predict the survival probability of individual patients with GEP-NETs.

DESIGN, SETTING, AND PARTICIPANTS

In this cohort study, 43 751 patients with GEP-NETs diagnosed from January 1, 1975, to December 31, 2015, were identified from the Surveillance, Epidemiology, and End Results Program. Associated data were used for epidemiologic and survival analysis, as well as the establishment and validation of a nomogram to predict the survival probability of individual patients with GEP-NETs. The study cutoff date was December 31, 2018. Statistical analysis was performed from February 1 to April 30, 2020.

MAIN OUTCOMES AND MEASURES

Incidence, factors associated with overall survival, and a nomogram model for patients with GEP-NETs.

RESULTS

A total of 43 751 patients received a diagnosis of GEP-NETs from 1975 to 2015 (22 398 women [51.2%], 31 976 White patients [73.1%], 7097 Black patients [16.2%], 3207 Asian and Pacific Islander patients [7.3%], 270 American Indian and Alaska Native patients [0.6%], and 4546 patients of unknown race [10.4%]; mean [SD] age at diagnosis, 58 [15] years). The age-adjusted incidence rate of GEP-NETs increased 6.4-fold from 1975 to 2015 (annual percentage change [APC], 4.98; 95% CI, 4.75-5.20; P < .001). Furthermore, among site groups, the incidence of GEP-NETs in the rectum increased most significantly (APC, 6.43; 95% CI, 5.65-7.23; P < .001). As for stage and grade, the incidence increased the most in localized GEP-NETs (APC, 6.53; 95% CI, 6.08-6.97; P < .001) and G1 GEP-NETs (APC, 18.93; 95% CI, 17.44-20.43; P < .001). During the study period, the mean age at diagnosis for localized disease increased by 9.0 years (95% CI, 3.3-14.7 years; P = .002), which remained unchanged for regional and distant cases. On multivariable analyses, age, sex, marital status, and tumor size, grade, stage, and site were significantly associated with overall survival for patients with GEP-NETs (eg, patients with distant vs localized disease: hazard ratio, 10.32; 95% CI, 8.56-12.43; G4 vs G1 GEP-NET: hazard ratio, 6.37; 95% CI, 5.39-7.53). Furthermore, a nomogram comprising age, size, grade, stage, and site was established to predict the 3-year and 5-year survival probability, with the concordance indexes of 0.893 (95% CI, 0.883-0.903) for the internal validations and 0.880 (95% CI, 0.866-0.894) for the external validations. The receiver operating characteristic curve demonstrated that the nomogram exhibited better discrimination power than TNM classification (area under the curve for 3-year overall survival, 0.908 vs 0.795; for 5-year overall survival, 0.893 vs 0.791).

CONCLUSIONS AND RELEVANCE

In this study, the incidence and prevalence of GEP-NETs have continued to increase over 40 years, especially among patients with rectal GEP-NETs. In addition, this study suggests that a nomogram with 5 prognostic parameters may accurately quantify the risk of death among patients with GEP-NETs, indicating that it has satisfactory clinical practicality.

Surgical Management of Primary Small Bowel NET Presenting Acutely with Obstruction or Perforation

Up to 35% of small bowel neuroendocrine tumors (SBNETs) may present with an acute intra-abdominal complication including obstruction, perforation, bleeding or ischemia and may require emergency surgical treatment in centers not normally accustomed to managing patients with neuroendocrine tumors. These patients may have a known diagnosis of SBNET, be suspected as suffering from SBNET or have SBNET diagnosed as an incidental finding on presenting radiology or postoperative pathology. Perioperative priorities include obtaining both clinical and radiological staging with cross-sectional imaging and clinical examination, screening for the presence of carcinoid syndrome and right-sided cardiac disease and assessment of prognosis. Intraoperatively careful attention should be paid to noting the presence and location of multifocal primary and metastatic disease. Ideally, surgical resection with mesenteric lymph node dissection is the treatment of choice for obstructing and perforating lesions. Extended lymphadenectomy along the SMA, SMV and behind the pancreas should be primarily considered an elective procedure. In unwell patients with advanced disease surgical bypass (jejuno or ileocolic) or proximal defunctioning should be undertaken but, given the excellent long-term survivals in patients with stage IV disease, could be considered bridging procedures to elective resection following formal staging and multidisciplinary review.

A Predictive Nomogram for Small Intestine Neuroendocrine Tumors

OBJECTIVE

There is a scarcity of prognostic tools for small intestine neuroendocrine tumors (SI-NETs) and inconsistencies in currently available grading and staging systems. Nomograms are being proposed to address these limitations. However, none is specific to the US population. This study proposed a concise nomogram for SI-NETs using US population-based data.

METHODS

Patients with SI-NETs (2004-2015) were selected from the Surveillance, Epidemiology, and End Results database. Variables selected were age, sex, race, tumor grade, primary tumor size, and TNM staging. Cox regression parameter estimates were used to generate nomogram scores.

RESULTS

A total of 2734 patients were selected: 2050 for nomogram development and 684 for internal validation. Prognosticators, age (P < 0.0001), primary tumor size >3 cm (P < 0.0022), tumor grade (P < 0.0001), depth of invasion ≥T3 (P < 0.0280), and distant metastasis (P < 0.0001) were used to develop the nomogram. Nomogram scores ranges from 10 to 80 points with an area under the curve of 0.76, which remained consistently high during internal validation (area under the curve, 0.75).

CONCLUSIONS

This Surveillance, Epidemiology, and End Results database nomorgram is a concise prognostic tool that demonstrated high predictive accuracy.

Prognostic Performance of Different Lymph Node Staging Systems in Patients With Small Bowel Neuroendocrine Tumors

Background: The prognostic significance of the lymph node (LN) classification for small bowel neuroendocrine tumors (SBNETs) remains unknown. The aim of the present study was to evaluate and compare the prognostic assessment of different LN staging systems. Methods: Patients with SBNETs were identified from the Surveillance, Epidemiology, and End Results (SEER) database. The X-tile program was used to determine the cutoff value of the resected lymph nodes (RLNs), negative lymph nodes (NLNs), lymph node ratio (LNR), and the log odds of positive lymph nodes (LODDS). Survival analyses were performed using Kaplan-Meier curves with log-rank test. Logistic regression analysis was used to evaluate the differences between different periods. Univariate and multivariate Cox proportional hazards models were used to assess the prognostic value of different LN staging systems on cause-specific survival (CSS). The relative discriminative abilities of the different LN staging systems were assessed using the Akaike information criterion (AIC) and the Harrell consistency index (HCI). Result: A total of 3,680 patients were diagnosed with SBNETs between 1988 and 2014 from the SEER database. A significant difference over time (1988-1999 vs. 2000-2014) was seen in age (P <0.001), tumor differentiation (P <0.001), T stage (P <0.001), and RLN (P <0.001) subgroups. Multivariate Cox survival analysis identified that LN status stratified by the number of RLNs, NLNs, LNR, and LODDS all predicted CSS in patients with SBNETs (all P <0.05), whereas the number of positive lymph nodes (PLNs) failed (P = 0.452). When assessed using categorical variables, LODDS staging systems showed the best prognostic performance (HCI: 0.766, AIC: 7,575.154) in the whole population. Further analysis based on different RLNs after eliminating the missing data showed that when the RLNs are <12, the LODDS (HCI: 0.769, AIC: 1,088.731) maintained the best prognostic performance as well when the RLNs are ≥12 (HCI: 0.835, AIC: 825.692). Among patients with LNR scores of 0 or 1, there was a residual heterogeneity of outcomes that were better stratified and characterized by the LODDS. Conclusion: LODDS was a better predicator of survival when LN status was stratified as a categorical variable and should be considered when assessing the prognosis of patients with SBNETs to allow a more reliable means to stratify patient survival.

Prognostic factors for death after surgery for small intestinal neuroendocrine tumours

Background

Neuroendocrine tumours of the small intestine (SI-NETs) are rare gastrointestinal neoplasms with an annual incidence of about one per 100 000. Patients with apparently similar tumours have variable outcomes. The aim of this study was to identify postoperative prognostic factors identifiable after initial surgery.

Methods

This was a nested case-control study of patients with SI-NETs who were treated between 1961 and 2001. Data were retrieved from the Swedish Cancer Registry. Patients who died from the SI-NET and corresponding controls (who outlived cases by at least 1 month), matched by age at diagnosis and calendar period, were included. Sex, postoperative symptoms, postoperative 5-hydroxyindoleacetic acid (5-HIAA) values, European Neuroendocrine Tumor Society (ENETS) stage, insufficiency of the tricuspid valve, radical secondary surgery and secondary malignancy were studied as potential prognostic factors.

Results

In total, 1122 patients were included (561 cases, 561 controls). Postoperative factors of prognostic importance included hormone-related symptoms, stage IV disease, raised levels of 5-HIAA, insufficiency of the tricuspid valve, secondary surgery not being macroscopically radical and a second malignancy.

Conclusion

Stage and symptomatic disease are important prognostic factors in SI-NET.

Prognostic Factors for Survival among Patients with Small Bowel Neuroendocrine Tumours Associated with Mesenteric Desmoplasia

BACKGROUND

Small intestinal neuroendocrine tumours (SI NETs) represent 30-50% of small bowel neoplasms and are often associated with diverse fibrotic complications. Mesenteric fibrosis is a hallmark of SI NETs which may cause substantial morbidity and is considered an adverse feature. However, survival analyses in this group of patients are lacking.

METHODS

The aim of this retrospective study was to determine the overall survival (OS) and factors affecting prognosis in a large cohort of 147 patients with SI NETs and radiological evidence of mesenteric desmoplasia from our centre. The severity of desmoplasia was graded radiologically and its effect on OS and long-term complications was assessed. The median follow-up period was 82 months.

RESULTS

The median OS was 8.7 years (95% CI 6.8-9.9) with an overall 5-year survival of 71%. The univariate analysis demonstrated that an age >65 years, a liver tumour burden >50% of the hepatic parenchyma, carcinoid heart disease, chromogranin A levels >10 times the upper limit of normal, and urinary 5-hydroxyindoleacetic acid (5-HIAA) levels >5 times the upper limit of normal were poor prognosticators, while primary resection was associated with a longer OS. However, only an age >65 years and urinary 5-HIAA levels >10 times the upper limit of normal remained statistically significant after multivariate analysis. The severity of mesenteric desmoplasia did not seem to demonstrate a statistically significant relationship to OS or long-term outcomes.

CONCLUSION

This study is the first comprehensive survival analysis of patients with SI NETs associated with mesenteric desmoplasia and has provided important and clinically relevant epidemiological data for this group of patients.

The Influence of Preoperative Symptoms on the Death of Patients with Small Intestinal Neuroendocrine Tumors

Background

Small intestinal neuroendocrine tumors (SI-NETs) are uncommon tumors with an annual incidence of about 1 per 100,000. Usually, SI-NETs have a slow progression, and patients often present with generalized disease. Many patients do well, and the disease has a relatively favorable 5-year survival rate. Some SI-NETs, however, have a more negative prognosis. This study aimed to establish prognostic factors for death identifiable at primary surgery.

Methods

A nested case-control study investigated 1150 patients from the cohort of all patients with a diagnosis of SI-NETs in Sweden between 1961 and 2001. The study cases consisted of all patients who died of SI-NETs during the study period. Each case was assigned a control subject matched by age at diagnosis and calendar period. Possible prognostic factors [gender, degree of symptoms, indication for surgery, World Health Organization (WHO) stage] were evaluated in uni- and multivariable analyses.

Results

The patients with symptomatic disease had an increased risk of dying. The indication for primary surgery influenced survival, showing a more negative prognosis for elective surgery. The WHO stage influenced survival, and stage 4 patients had an almost threefold risk of dying compared with stages 1 to 3b patients.

Conclusions

This study showed that preoperative symptoms are important in prognostication for SI-NETs. Hormonal symptoms generally signify a patient with a more advanced disease stage and a worse prognosis. Including symptomatic disease together with the WHO stage and grade could possibly increase the accuracy of prognostication.

Blood measurement of neuroendocrine gene transcripts defines the effectiveness of operative resection and ablation strategies

BACKGROUND

Surgery is the only curative treatment for gastroenteropancreatic neuroendocrine tumors (GEP-NETs), but the prediction of residual disease/recurrence is limited in the absence of optimal biomarkers. We examined whether a blood-based multianalyte neuroendocrine gene transcript assay (NETest) would define tumor cytoreduction and therapeutic efficacy.

METHODS

The NETest is a polymerase chain reaction-based analysis of 51 genes. Disease activity is scaled 0-100%; minimal <14%, low 14-47%, and high >47%. A total of 35 GEP-NETs in 2 groups were evaluated. I: after surgery (R0, n = 15; residual, n = 12); II: nonsurgery (n = 8: embolization with gel-foam alone [bland: n = 3]), transarterial chemoembolization (n = 2), and radiofrequency embolization (n = 3). Measurement (quantitative real-time-polymerase chain reaction) and chromogranin A (CgA; enzyme-linked immunosorbent assay) were undertaken preoperatively and 1 month after treatment.

RESULTS

NETest score was increased in 35 (100%) preoperatively; 14 (40%) had increased CgA (χ(2) = 30, P < 2 × 10(-8)). Resection reduced NETest from 80 ± 5% to 29% ± 5, (P < .0001). CgA decrease was insignificant (14.3 ± 1.6 U/L to 12.2 ± 1.7 U/L). NETest decreases correlated with diminished tumor volume (R(2) = 0.29, P = .03). Cytoreduction significantly reduced NETest from 82 ± 3% to 41% ± 6, P < .0001). CgA was not decreased (21.4 ± 5.5 U/L to 18.4 ± 10.1 U/L). Four (36%) of 11 R0s with increased NETest at 1 month developed positive imaging (sensitivity 100%, specificity 20%). One hundred percent (ablated group) were transcript- and image-positive.

CONCLUSION

Blood NET transcripts delineate surgical resection/cytoreduction and facilitate identification of residual disease.

Retrospective analysis of the clinicopathological characteristics of gastrointestinal neuroendocrine neoplasms

The aim of the present study was to analyze and summarize the clinicopathological characteristics and factors affecting prognosis for patients with gastrointestinal neuroendocrine neoplasms (GINENs). Retrospective analysis was conducted on the clinicopathological data of 74 patients who were diagnosed with GINEN, and immunohistochemical methods were used to detect the expression levels of relevant markers [synaptophysin (Syn), chromogranin A (CgA) and Ki-67]. Among the 74 cases with GINEN, there were 39 males and 35 females, with an average age of 56.9 years. There were 32 neoplasms in the rectum, 29 in the stomach, 6 in the colon, 2 in the small intestine and 5 in the appendix. All 74 cases underwent surgical resection. According to the World Health Organization Classification of Tumors of the Digestive System (2010), the diagnosis of the 74 cases showed 41 cases (55.4%) of neuroendocrine tumor (NET; 25 cases of G1 and 16 cases of G2), 21 cases (28.4%) of neuroendocrine carcinoma (NEC) and 12 cases (16.2%) of mixed adenoneuroendocrine carcinoma (MANEC). Additionally, 19 cases had metastasis to lymph nodes. During 10-34 months of follow-up, 15 patients had distant metastasis and 24 patients succumbed, and the accumulative survival rate in 1 or 2 years was 87.8 and 74.3%, respectively. Six factors, namely neoplasm size, depth of invasion, lymph node metastasis, distant metastasis, pathological type and the expression or lack of expression of CgA, significantly affected the survival time of patients. Definitive diagnosis of GINEN mainly relies on pathological diagnosis. GINENs with different histopathological types and grading have different clinicopathological characteristics and prognosis: NETs are mainly early lesions with a good prognosis, whereas NECs and MANECs have high malignancy and strong invasion with a worse prognosis.

Gastrointestinal carcinoid: epidemiological and survival evidence from a large population-based study (n = 25 531)

BACKGROUND

Owing to its rarity, the published evidence on gastrointestinal (GI) carcinoid is often based on small series of patients or population-based studies regarding all neuroendocrine tumors. Here, we present a comprehensive epidemiological and survival analysis of the largest cohort of patients with GI carcinoid ever reported.

PATIENTS AND METHODS

Patients with histological diagnosis of GI carcinoid (n = 25 531) were identified from the Surveillance Epidemiology End Results (SEER) database (including 18 USA cancer registries and spanning the 1973-2009 time frame). Demographic and disease data were used for epidemiological and survival analyses.

RESULTS

The incidence of GI carcinoid is steadily increasing over the past three decades at a rate higher than any other cancer [annual percentage change (APC) = 4.4, 95% confidence interval (CI) 4.0-4.8]. These patients have a higher risk of further primary tumor (standardized incidence ratio, SIR = 1.15, 95% CI 1.10-1.21), but also a reduced risk of skin melanoma (SIR = 0.64, 95% CI 0.41-0.95). Despite the overall favorable prognosis (5-year disease-specific and relative survival rate: 91.3% and 87.4%, respectively), the mortality rate is increasing over time (APC = 3.5, 95% CI 3.0-4.0) and the 5-year survival rate of patients dying of GI carcinoid (28.5%), though better than that reported for GI cancers in general (8.4%), cannot be considered satisfactory. Finally, a nomogram is provided to predict patient survival on the basis of clinico-pathological factors independently associated with prognosis at multivariate analysis.

CONCLUSIONS

These findings can be clinically useful for the management of patients with GI carcinoid and eagerly prompt the continuous effort to develop more effective therapeutic strategies against this slow-growing but chemoresistant tumor.

ENETS TNM Staging Predicts Prognosis in Small Bowel Neuroendocrine Tumours

Introduction. Small bowel neuroendocrine tumours (NETs) are the most common type of gastrointestinal neuroendocrine tumours. The incidence and prevalence of these tumours are on the rise. The aims of this study were to determine prognostic clinicopathological features and whether the ENETS TNM staging system predicts prognosis and also. Method. Clinical data was collected retrospectively from 138 patients with histologically proven small bowel NETs managed at King's College Hospital. Histology was reviewed and small bowels tumours, were staged according to the ENETS TNM staging system. Results. Median age was 65 years (range 29–87). The 5-year survival was 79.5% and the 10-year survival was 48.5%. Resection of the primary tumour was associated with improved survival (120 versus 56 months, P < 0.05). On multivariate analysis prognostic factors were primary tumour resection and not having a carcinoid heart disease. TNM staging significantly separated survival of stage 2 and stage 3 from stage 4 NETs. Conclusion. Small bowel primary tumour resection and not having carcinoid heart disease are prognostic factors. The ENETS TNM staging and grading system appears to be of prognostic relevance to small bowel NETs.