Citations

Objectives A platinum/etoposide doublet is standard first-line therapy for poorly differentiated neuroendocrine carcinoma (PD NEC); however, evidence to guide treatment beyond first-line regimens is lacking. This study aimed to evaluate the efficacy of second-line regimens in PD NEC. Methods We performed a retrospective analysis of patients treated with second-line chemotherapy for PD NEC. Inclusion criteria were previous first-line therapy with platinum/etoposide, extrapulmonary PD NEC, and follow-up data. The primary end points were overall survival (OS) and progression-free survival (PFS) after second-line therapy. Secondary end points included OS and PFS from first-line therapy. Results Sixty-four patients were included. The median OS from initiation of second-line therapy was 6.2 months (95% confidence interval [CI], 4.9–8.9). The median PFS was 2.3 months (95% CI, 2.0–3.2). No second-line regimen showed a statistically significant difference in OS or PFS. There was a significant increase in OS for cisplatin first-line regimens compared with carboplatin (17.0 months [95% CI, 12.5–22.6] vs 11.7 months [95% CI, 8.0–14.0]). Conclusions The efficacy of current second-line therapy in PD NEC is poor. No second-line regimen showed statistically significant superiority. Cisplatin was associated with longer OS regardless of second-line regimen or age. However, unmeasured confounders such as performance status or comorbidities may explain this effect.

e20029 Background: Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a pulmonary disorder with neuroendocrine cell proliferation with potential progression to lung neuroendocrine tumor (Lu-NET). Optimal diagnostic and treatment strategies have yet to be well defined. Herein, we aim to describe the Mayo Clinic experience with DIPNECH. Methods: A retrospective analysis was performed of patients diagnosed with DIPNECH within Mayo Clinic between January 2000-Febuary 2019. Cases were identified from clinical databases at Mayo Clinic. Data on demographics, disease characteristics, time of diagnosis, surgery, and last follow up date were extracted. Extent of symptom burden, treatment approaches, disease progression, and disease-free survival (DFS) were evaluated by chart review. Results: A total of 59 patients were identified with a median age of 63(43-81) years. The cohort was predominantly female (93.2%) and non-smoking (76.3%). Most patients (86.4%) had symptomatic disease with chronic cough being the most common (71.2%) followed by exertional dyspnea (44.1%). Imaging typically showed bilateral lung nodules (93.2%) with mosaic attenuation noted 69.5% of the time. Surgical resection was frequently completed to confirm diagnosis (94.9%). Most patients received inhaled glucocorticoids combined with a beta agonist (79.7%). Oral steroid use was seen in 49.2% of patients whereas a somatostatin analog was used in 15.3% following the diagnosis of DIPNECH. These medical interventions led to symptom relief in 23.7% of the patients. The median follow up for all patients was 19.5 months. Progression of tumorlets was seen in 48.7% of patients with only 7(17.9%) patients progressing to a diagnosis of Lu-NET. The 3-year DFS was 90.5%. Conclusions: This is amongst the largest studies completed evaluating DIPNECH patients. DIPNECH remains a rare disease more commonly diagnosed in women in their early 60’s. DIPNECH appears to have an indolent course with obstructive symptoms being the most common finding. A minority of patients experienced symptom relief with therapy. Overall, DIPNECH appears to have a low risk of progressing to Lu-NET based on the observation of this study.

4127 Background: Small bowel adenocarcinoma (SBA) is a rare tumor accounting for less than 2% of all GI tumors. The prognosis of advanced disease is poor. Benefits of adjuvant therapy following complete resection are uncertain. Methods: We retrospectively reviewed the records of 491 pts with primary SBA diagnosed at the Mayo Clinic from 1970–2005. Patients with ampullary and periampullary tumors were excluded. Results: 303 pts (62%) were male and the median age was 62 years. 280 (57%) of the tumors were located in the duodenum, 143 (29%) in the jejunum, 48 (10%) in the ileum and in 20 (9%) the location was not specified. Abdominal pain was the most common principal symptom occurring in 203 pts (43%), followed by anemia/GI bleeding in 104 pts (22%) and nausea/vomiting in 76 pts (16%). The most common histologic grading was 3, occurring in 224 pts (45%). 79 pts (16%) grade 4, 170 pts (35%) grade 2, with 7 (1.4%) grade 1. The TNM staging was as follows: 0: 3 (0.6%), I: 36 (7.3%), II: 133 (27.1%), III: 137 (27.9) and IV: 163 (33.2). In 18 pts (3.7%), data were insufficient for staging. The median survival for the entire cohort was 20.7 months, with 5 and 10 year survival 26% and 19% respectively. Increasing age (p < 0.0001), male sex (p = 0.026), advanced stage (p < 0.0001), grade 4 tumors (p = 0.005) and residual disease after surgery (p < 0.0001) were independently associated with shortened survival in a multivariate analysis. Neither adjuvant chemoradiation (n = 40) nor 5-FU based chemotherapy (n = 33) improved overall survival after complete resection, even after adjusting for age, sex, location, lymph node status and grade (RR 1.17, p = 0.45). This remained true for the subset of patients with resected duodenal tumors as well (RR 1.06, p = 0.83). The use of chemotherapy was associated with prolonged survival in patients with metastatic disease. The median survival and 1-year survival was 15.3 mos vs. 3.1 mos and 59% vs. 5.9% respectively (p < 0.0001), in this highly selected group. Conclusion: SBA is a rare tumor with a relatively poor prognosis. Complete resection of all disease offers the only chance of cure. The benefits of adjuvant therapy remain unknown, but chemotherapy in the metastatic setting may provide survival benefit. No significant financial relationships to disclose.

4584 Background: PETs (islet cell tumors) are uncommon and often indolent tumors, but little is known about the incidence of PETs in the US and trends in survival. Methods: The SEER registry was used to identify cases of functional PETs (fPETs) and non-functional PETs (nfPETs) diagnosed from 1973–2000. Benign insulinomas were excluded. Incidence rates were age adjusted to the standard US population for 2000. Results: Of 971 patients with PETs, 824 (85%) were nfPETs, 37 (4%) were malignant insulinomas, 88 (9%) were fPETs other than insulinoma, and data were missing for 22 (2%). The crude annual incidence of PETs (per 100,000) for all ages was 0.1 in females and 0.2 in males. The incidence was highest in the age group >70 years (0.4, Table ). Tumors were localized in 109 (11%), regionally advanced in 228 (23%), and distant metastases were present in 545 (56%). Patients with fPETs were younger than patients with nfPETs (mean age 54.2 vs. 57.6, p=0.038) and had a longer median survival (MS) (47 vs. 30 months (mos), p=0.001) but were as likely to have advanced disease (p=0.50). The 5 and 10 year overall survival was 45.3% vs. 32.7% and 31.7% vs. 18.1% for fPETs vs. nfPETs, respectively. MS was 95 mos for localized PETs, 66 mos in regionally advanced PETs and 19 mos for distant metastases (p<0.001). Race did not influence incidence and survival. On multivariate analysis, only age (p<0.0001) and stage (<0.0001) were independently associated with prognosis but the functional status of the tumor approached significance (p=0.053). Survival has improved over time with longer MS in patients diagnosed in later quartiles of the observation period (p<0.001, Table). This difference is not explained by stage migration, as patients in all four quartiles had a similar stage distribution (p=0.79). Conclusions: PETs are uncommon tumors and the prognosis is highly dependent on the stage and the age of the patients. Patients with fPETs may have a better prognosis than nfPETs. Survival has improved over time. [Table: see text] No significant financial relationships to disclose.

630 Background: Neuroendocrine tumors (NET) are heterogeneous in terms of prognosis based on location, grade, and stage. In this study we report causes of deaths (COD) in patients with NET. Methods: We used the Surveillance, Epidemiology, and End Results (SEER) Program to query data of NET patients diagnosed between 2000 and 2016 and report COD following NET diagnosis. Results: We reviewed 94,399 NET cases of which 38,692 died during the follow-up period. The highest number of deaths (5,721) occurred within less than a year following grade 3 (G3) NET diagnosis while most deaths in grade 1/2 (G1/G2) cases occurred within 1-5 years of diagnosis (1,889 and 987, respectively). During the first year of diagnosis, most deaths were from NETs (73%), followed by other cancers (11.2%) and cardiac diseases (CD) (4.6%). As time passed, NET deaths decreased to be responsible for 24.3% of deaths after > 10 years of diagnosis, while other cancers (14%) and CD (19.7%) became more common. When dividing NET cases by grade, NETs were responsible for 42.8%, 63.4%, and 81.2% of deaths in G1, G2, and G3, respectively, while other cancers were responsible for 16.2%, 11.8%, and 7.2% of deaths, respectively and CDs were responsible for 12.3%, 7.2%, and 3.2% of deaths, respectively. For G1 localized NET: non-NET cancers (22.2%) was the most common COD followed by NET (19.7 %) and CD (16.8%). For G2 localized NET, NET was COD in 31.1% of cases followed by non-NET cancers (22.4%) and CD (13.8%). In metastatic disease, NET was the most common COD regardless of grade. Conclusions: In G1 and G2 localized NET, deaths were mostly secondary to non-NET causes. Therefore, counseling patients regarding survivorship with cancer-screening and focusing on prevention from non-cancer deaths is important. On the other hand, NET is responsible for most deaths in metastatic NET regardless of grade. Further advances in systemic therapies are needed to improve the outcomes of advanced disease.

Abstract This manuscript is the result of the North American Neuroendocrine Tumor Society consensus conference on the surgical management of pancreatic neuroendocrine tumors from July 19 to 20, 2018. The group reviewed a series of questions of specific interest to surgeons taking care of patients with pancreatic neuroendocrine tumors, and for each, the available literature was reviewed. What follows are these reviews for each question followed by recommendations of the panel.

Background: Adherence to surveillance guidelines in resected colon cancer has significant implications for patient morbidity, cost of care, and healthcare utilization. This study measured the underuse and overuse of imaging for staging and surveillance in stage I–II colon cancer. Methods: The OptumLabs database was queried for administrative claims data on adult patients with stage I–II colon cancer who underwent surgery alone in 2008 through 2016. Use of PET and CT imaging was evaluated during both initial staging (n=6,921) and surveillance for patients with at least 1 year of follow-up (n=5,466). “High use” was defined as >2 CT abdominal/pelvic (CT A/P) or PET scans per year during surveillance. Results: Overall, 27% of patients with stage I–II colon cancer did not have a staging CT A/P or PET scan and 95% did not have a CT chest scan. However, rates of staging CT A/P and CT chest scans increased from 62.0% (2008) to 74.8% (2016) and from 2.3% (2008) to 7.1% (2016), respectively. Staging PET use was overall very low (5.2%). During surveillance, approximately 30% of patients received a CT A/P or PET and 5% received a CT chest scan within the first year after surgery. Of patients who had surveillance CT A/P or PET scans, the proportion receiving >2 scans within the first year (high use) declined from 32.4% (2008) to 9.6% (2016) (P = .01). Conclusions: Although PET use remains appropriately low, many patients with stage I–II colon cancer do not receive appropriate staging and surveillance CT chest scans. Among those who do receive these scans during surveillance, high use has declined significantly over time.

Abstract Introduction: The role of surveillance imaging in diffuse large B-cell lymphoma (DLBCL) after treatment with curative intent is debated. In 2013, the American Society of Hematology (ASH) Choosing Wisely® campaign (Hicks LK, et al. Blood 2013) released a recommendation to "limit surveillance CT scans in asymptomatic patients following curative-intent treatment for aggressive lymphoma." This was based on previous studies demonstrating a lack of survival benefit as well as a significant impact on the patient in terms of cost, anxiety, incidental findings and radiation exposure. Similar findings have been described regarding the use of PET imaging, especially in low risk patients. We aimed to study the changes in practice patterns of surveillance imaging for DLBCL survivors treated with curative intent before and after the publication of the ASH Choosing Wisely® campaign. Methods: Administrative claims data from a large U.S commercial insurance database (OptumLabs Data Warehouse) were used to retrospectively identify adult patients with an incident diagnosis of DLBCL between 2008 and 2016 and at least one year of follow-up. We excluded those who did not receive treatment with curative intent: RCHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) x 6 cycles or RCHOP x 3-5 cycles plus radiation. Patients were also excluded if they had a co-existing or second cancer, or if they received any chemotherapy/radiation during their surveillance period, as to exclude anyone with a recurrence of their lymphoma. The surveillance period started 90 days after the last chemotherapy or radiation and continued for the duration of follow-up. Surveillance imaging was defined as any PET, PET-CT, CT chest, CT abdomen, and/or CT pelvis. To examine trends over time, three time periods were defined: 2008-2010, 2011-2013 and 2014-2016. The Cochran Armitage test was used to test the trend hypothesis. Results: A total of 1,472 patients were included. Cohort characteristics by time period are described in Table 1. Surveillance imaging frequency decreased from 84% in Year 1 of surveillance to 43% in Year 5 (Figure 1). Overall, surveillance imaging during the first 3 surveillance years significantly decreased over the three time periods (Figure 2) (P<0.01 for Years 1 and 2, P=0.04 for Year 3). Imaging surveillance for the first two years of surveillance did not significantly decrease from 2008-2010 to 2011-2013 (P>0.05), but significantly decreased from 2011-2013 to 2014-2016 (P<0.01). Of the groups that received imaging surveillance during year 1, the median number of scans during the first year was 2 (inter-quartile range, 1-2) and did not significantly change over time. In addition, PET/PET-CT surveillance decreased from 49% in Year 1 to <10% in Year 5. PET/PET-CT also decreased over the three time periods, from 62% (2008-2010) to 48% (2011-2013) to 43% (2014-2016) during the first year of surveillance and 40% to 31% to 25% during the second year. Younger age (<65 years versus ≥65 years) was associated with higher imaging utilization (86% versus 81%, respectively), and specifically PET/PET-CT utilization (55% versus 43%, respectively), during the first year of surveillance. However, race (white versus non-white) did not significantly affect imaging (85% versus 83%) or PET utilization (50% versus 47%) during the first year of surveillance. Conclusions: Our study demonstrates that the rate of surveillance CT and PET imaging in DLBCL patients treated with curative intent decreased significantly in the years after the publication of the ASH Choosing Wisely® campaign. However, over half of the DLBCL patients diagnosed in 2014-2016 continued to undergo surveillance imaging, indicating either incomplete guideline dissemination or ongoing debate regarding optimal surveillance practice. Future studies are necessary to determine whether such a decline in surveillance imaging is sustained and to examine factors (patient, provider, and payer) associated with surveillance imaging in DLBCL. Disclosures No relevant conflicts of interest to declare.

Neuroendocrine neoplasms (NENs) are malignancies with rare reports of central nervous system development. A 34-year-old woman was found to have a primary NEN of the brain, and she had recurrence with identical histology 10 years later. Extracranial NENs were excluded. She had routine surveillance for the first 5 years with MRIs and positron emission tomography/CTs after the initial presentation which was treated with radiation followed by cisplatin and etoposide. This case highlights the difference in primary NENs versus NEN metastases to the brain, and that longer periods of surveillance are likely required for primary NENs. This is important because the prognosis between primary NENs and metastatic NENs to the brain are vastly different and should not be treated as equal diseases. The patient eventually died of her recurrence secondary to complications of a ventriculoperitoneal shunt placed for treatment of hydrocephalus from the disease.

Abstract Neuroendocrine tumors (NETs) arise from enterochromaffin cells found in neuroendocrine tissues, with most occurring in the gastrointestinal tract. The global incidence of NETs has increased in the past 15 years, likely due to better diagnostic methods. Small-bowel NETs are frequently associated with carcinoid syndrome (CS). Carcinoid syndrome diarrhea occurs in 80% of CS patients and poses a substantial symptomatic and economic burden. Patients with CS diarrhea frequently suffer from diarrhea and flushing and report corresponding impairment in quality of life, requiring substantial changes in daily activities and lifestyle. Treatment paradigms range from surgical debulking to liver-directed therapies to treatment with somatostatin analogs, nonspecific anti-diarrheal agents, and a tryptophan hydroxylase inhibitor. Other causes of diarrhea, including steatorrhea, short bowel syndrome, and bile acid malabsorption, should be considered in NET patients with refractory diarrhea. More therapeutic options are needed for symptomatic management of patients with NETs, and better understanding of the pathophysiology can empower clinicians with improved patient care.