Hálfdánarson, Þorvarður R.

e21575 Background: The clinical significance of brain metastases in patients with bronchopulmonary neuroendocrine (NE) tumors is unknown; we therefore conducted a population based analysis to evaluate the implications of brain metastases in these patients. Methods: The NCDB database was queried to identify patients with stage IV bronchopulmonary NE tumors treated between the years of 2004-2012. Patients were split into two groups based on the presence of brain metastases at diagnosis and survival probabilities with multivariate models were performed. Results: A total of 7,725 patients with Stage IV bronchopulmonary NE tumors were identified. The histological subtypes studied in this cohort were NE carcinoma (65.4%), large cell NE carcinoma (30.5%), typical carcinoid (2.8%) and atypical carcinoid (1.3%) . The patients included in this study were mainly white (86.4%) men (56.8%) with a median age of 67 years who had liver (9.5%), bone (6.2%) and brain (5.9%) metastases at diagnosis. The median overall survival (OS) of the cohort was 5.59 (95% CI: 5.4-5.8) months, but when OS was stratified by histological subtype it was significantly better in patients with typical carcinoid (table). In the whole cohort, the median OS did not differ between patients with and without brain metastases (5.55 vs. 5.68; p = 0.24). However, a sensitivity analysis by histology showed that the presence of brain metastases worsen the median OS of patients with typical carcinoid only (15.1 vs 4.6, p = 0.04). An adjusted multivariate analysis restricted to patients with brain metastases showed that administration of systemic chemotherapy (HR:0.5; 95% CI:0.35-0.72, p < 0.001) and resection of distant metastases (HR:0.5; 95% CI:0.29-0.88, p = 0.017) were the two most powerful independent prognostic factors. Conclusions: The presence of brain metastases negatively impact survival of patients with typical carcinoids but not in those with the other histological subtypes included in this study. Staging MRI should be strongly considered at diagnosis in patients with bronchopulmonary NE tumors, due to the sizable proportion of these patients presenting with brain metastases and also due to its prognostic value in a subset of this population. [Table: see text]

e21007 Background: There is a lack of data to guide the management of resectable bronchopulmonary carcinoid tumors (BCTs). Methods: The NCDB database was retrospectively reviewed to analyze the roles of surgery, chemotherapy and radiation. Patients with a diagnosis of clinically staged T1-2/N0-1 typical carcinoid (TC) and atypical carcinoid (AC) between 2004-2012 were included. Kaplan-Meier methods and multivariable analysis were performed. Results: A total of 2148 patients (TC 1874 & AC 274; T1/1648 & T2/500) were identified. The median age was 59 (range 18-89). There was a female (69.7%) and right lung (56.9%) predominance. Fifty-three patients received pneumonectomy, 68 chemotherapy, and 84 radiation therapy. The impact of age, histology (TC vs. AC), medical comorbidities (Charlson/Deyo score 0 vs. ≥1) and type of surgery [sublobar resection (SR) vs. lobectomy vs. lobectomy with mediastinal lymph node dissection (L/MLND)] were subsequently examined. AC, older age, and comorbidities were associated with shorter overall survival (OS) by both univariate and multivariable analysis. Patients who underwent lobectomy had longer OS (119 months) than those with SR (109 months) or L/MLND (115 months). However, this association was not significant by multivariable analysis with age incorporated as either a categorical ( < 60 vs. ≥60) or a continuous variable (Table). In the subgroup analysis of patients with T1, T2, TC and AC respectively, type of surgical resection was not significantly associated with OS by multivariable analysis. Conclusions: Patients with resectable BCTs have excellent OS. Atypical histology, older age, and comorbidities predicted inferior OS. There were insufficient data to support the use of perioperative chemotherapy or radiation therapy. Lobectomy was associated with prolonged OS by univariate analysis but this was not significant in the multivariable model, suggesting that SR is a reasonable approach for patients who cannot tolerate lobectomy. MLND did not seem to provide additional survival benefits. [Table: see text]

e19120 Background: The incidence and prevalence of Neuroendocrine Neoplasms (NENs) are rapidly rising. Epidemiologic trends have been reported for common NENs, but specific data for lung NENs has been lacking. Methods: We conducted a retrospective population-based analysis utilizing the Surveillance, Epidemiology, and End Results (SEER) database, and studied lung NENs patients from 1988 to 2015. Associated population data was utilized to report the annual age-adjusted incidence and overall survival trends. Trends in the incidence and survival of large-cell lung cancer (LCLC) and atypical carcinoid (AC) were reported from 2000-2015, while that for typical carcinoid (TC) and small cell lung cancer (SCLC) were reported from 1988-2015. Results: We examined a total of 115,995 lung NENs [103,980 – SCLC; 3,303 – LCLC; 8,146 – TC; 656 – AC]. The age-adjusted incidence rate revealed decline in SCLC from 8.6 in 1988 to 5.3 in 2015 per 100,000; while other NENs showed an increase: TC increased from 0.57 in 1988 to 0.77 in 2015 per 100,000, AC increased from 0.17 in 2001 to 0.22 in 2015 per 100,000, and lastly, LCLC increased from 0.35 in 2001 to 0.41 in 2015 per 100,000. On multivariable analyses, the median overall survival (OS) and disease-specific survival (DSS) rate varied significantly by stage, grade, age at diagnosis, histological type, insurance type, marital status, and race. The 5-year OS rate among SCLC and LCLC patients was 5% and 17%, respectively, consistent with their high-grade nature. On the other hand, TC and AC, representing low-grade neuroendocrine tumors, had good 5-year OS: 84% and 64%, respectively. Conclusions: The incidence of lung NENs is rising, possibly because of advanced radiological techniques. However, we have seen a downtrend in the incidence of SCLCs likely because of declining smoking habits. Such population-based studies are essential for resource allocation and to prioritize future research directions.

e16752 Background: Undifferentiated osteoclast-like giant cell carcinoma of the pancreas is an aggressive malignancy only described by a few case reports in the literature. In this study, we sought to better characterize this entity by examining patients seen at Mayo Clinic. Methods: This study identified patients with osteoclast-like giant cell carcinoma of the pancreas using Mayo Clinic databases (MN, AZ, FL) from the year 2000 to present. Patient demographics, genetic data, and treatment modalities were reviewed. Kaplan-Meier analysis was used to evaluate median overall survival (mOS) for the cohort as well as mOS and mPFS for treatment subgroups. Results: 15 patients were identified (9 female, 6 male). Median age at diagnosis was 59 years and mOS for all patients was 11.0 mos (95% CI 6.2-15.7 mos). 3 patients (20%) had metastatic disease at diagnosis with the liver being the most common site (n = 3). Metastatic disease was associated with significantly shorter OS (3.5 vs. 14.1 mos, p = 0.005; HR 7.98 [95% CI 1.43-44.4]) compared to locoregional disease (LRD). 4 patients underwent genetic testing. The most common mutation was CDKN2A (n = 3), followed by TP53 (n = 2) and KRAS (n = 2). 13/15 patients had detailed follow-up information. 6/7 patients undergoing chemotherapy received a gemcitabine-based regimen as first line: with capecitabine (n = 2), with nab-paclitaxel (n = 2), or as monotherapy (n = 2). 1 patient received FOLFIRINOX. In patients with LRD and adequate follow-up (n = 11), 8/11 underwent surgical resection and had longer OS compared to those without resection (17.0 vs. 8.4 mos, p = 0.09). No surgical patients received neoadjuvant chemotherapy. 5/8 received adjuvant chemotherapy, 2 did not undergo chemotherapy, and 1 was lost to follow-up after surgery. PFS from time of surgery was 15.3mos (95% CI 5.0-25.6mos). 6 patients (40%) were alive at time of analysis; all 6 underwent surgical resection. Conclusions: Osteoclast-like giant cell carcinoma of the pancreas is a rare malignancy with a poor prognosis, even when diagnosed at an early stage. OS for patients of all stages in this study was less than 1 year suggesting prognosis may be even worse than that of pancreatic adenocarcinoma. The optimal therapy remains unknown but most patients received similar chemotherapy as in adenocarcinoma. Patients with LRD amenable to surgical resection experienced a PFS over 1 year from surgery, possibly associated with OS benefit, however overall prognosis is poor. Further study is warranted on a larger scale to better understand disease course and treatment options.

e16705 Background: The prevalence of pancreatic neuroendocrine tumors (PNETs) has increased in the last decade. Despite being clinically asymptomatic PNETs can be biologically aggressive. There is currently no reliable non-invasive diagnostic biomarker for PNETs. In this study we aimed to identify and validate methylated DNA marker (MDM) candidates that differentiate PNET from normal pancreas. Methods: For discovery, reduced representation bisulfite sequencing (RRBS) was performed on DNA extracted from frozen normal pancreas (n = 13) and PNET (n = 51) tissues. Area under the receiver operator characteristic curve (AUC), fold-change, and p-value criteria selected candidates MDMs for blinded validation in independent FFPE tissues from primary PNET (n = 67; solid = 50, cystic = 17), normal pancreas controls (n = 24), and normal buffy coat (n = 36) using methylation specific PCR. MDM distributions in primary PNETs were compared to primary lung (n = 36) and small bowel (n = 36) NETs and metastatic PNET tissue (n = 25). The discrimination accuracy of candidate markers was summarized as the AUC with corresponding 95% confidence intervals (CI). Results: From the RRBS discovery, 31 candidate MDMs were selected for validation. Four MDMs ( SRRM3, HCN2, SPTBN4 and TMC6) achieved individual AUCs ≥0.95 in the validation set (Table). These MDMs were similarly discriminant in metastatic PNET tissue and in primary lung and small bowel NETs. Three out of these 4 MDMs perfectly differentiated PNET tissue from buffy coat with AUC of 1 and may be ideally suited for further development of a blood-based assay. Conclusions: We identified and validated novel MDMs in tissue that discriminate PNETs from controls with normal pancreas and buffy coat with high accuracy. These MDMs also differentiated metastatic PNETs from normal pancreas tissue. Further exploration of these candidate tissue MDMs in plasma can potentially guide diagnosis and management of PNETs. Funding: P30DK084567. [Table: see text]

e16702 Background: There are only a few reports examining the treatment patterns for poorly differentiated rectal/anal NEC. In this study, we sought to report treatment and survival outcomes for patients with NEC of the anus and rectum seen at Mayo Clinic. Methods: We identified patients with a primary NEC of the anus or rectum using Mayo Clinic databases (Minnesota, Arizona, Florida) from the year 2000 to present. NEC identified within polyps on colonoscopy was excluded from this study. Patients’ demographics were compiled. Kaplan Meier analyses were performed to evaluate overall survival (OS) for all patients, as well as subgroups with locoregional disease (LRD) and metastatic disease at diagnosis. Progression free survival (PFS) was also evaluated for patients with LRD treated with chemoradiation therapy (CRT). Results: 38 patients with NEC of the anus/rectum were identified with a median age of 55.5 years. 23 patients (61%) had metastatic disease at diagnosis and 15 (39%) had LRD. The most common site of metastasis was the liver (n = 20). Patients with metastatic disease at presentation had significantly shorter OS compared to patients with LRD (median OS 10.4 vs. 18.9 months, p = 0.039; HR 2.46, 95% CI [1.001-6.050]). 34 total patients received chemotherapy (ORR 11.8%), with platinum + etoposide (EP) being the most common first-line chemotherapy (n = 26). 10 of 15 patients with LRD received CRT (9 with EP and 1 with 5-FU) with median PFS of 6.3 months (95% CI 2.3-16.5 months), a 1-year PFS rate of 20%, and median OS of 18.6 months (95% CI 13.5-23.7 months). 2/10 received induction chemotherapy prior to CRT with 6/10 undergoing primary tumor resection (1 prior to CRT and 5 after CRT). Only 3 CRT patients were living at time of analysis (all underwent surgical resection), 2 without any active disease, 1 who achieved complete response with CRT then suffered recurrence and is still undergoing treatment. Conclusions: NEC of the anus and rectum is an aggressive malignancy with most patients experiencing metastatic disease at presentation and poor response to chemotherapy at all stages. Even those with LRD experience a very poor prognosis with OS of 18.9 months from diagnosis. For LRD, most patients underwent CRT with only a short-lived response (median PFS 6.3 months). Those achieving sustained response also underwent surgical resection. Overall, prognosis is poor for all stages and further study on a large scale is warranted to better characterize this rare, aggressive malignancy.

e16691 Background: Recent WHO classification of NET has defined high-grade well-differentiated NET (NET G3) as a distinct entity that is clinically different from neuroendocrine carcinoma. The optimal treatment for NET G3 has not been well-described. This study aims to evaluate NET G3 response to different treatment regimens. Methods: This is a retrospective study of NET G3 patients within the Mayo Clinic database (Arizona, Florida, and Minnesota). Patient demographics along with treatment responses and survival were assessed. Primary end points were progression-free survival (PFS) and objective response rate (ORR) by RECIST 1.1 criteria. Results: 71 patients with NET G3 were identified. Systemic treatment data was available in 30 patients who had a median age of 59.5 years at time of diagnosis. The primary tumor was most commonly pancreatic (73.3%). Ki 67 index was ≥55% in 26.7% of cases. 56.7% of cases had > 1 metastatic site. Treatment regimens included: capecitabine+temozolomide (CAPTEM) (n = 20), somatostatin analog (SSA) (n = 14), carboplatin/cisplatin+etoposide (EP) (n = 7), everolimus (n = 2), FOLFOX (n = 7), and lutetium Lu 177 DOTATATE (PRRT) (n = 10). CAPTEM was the most commonly used regimen (10 first-line, and 10 second-line) with ORR of 35%, disease control rate (DCR) of 65%, and median PFS of 9.4 months. The table summarizes the treatment data and responses rates for the various therapies used. Conclusions: Among NET G3 patients treated at Mayo Clinic, CAPTEM was found to be the most commonly used treatment with reasonable efficacy and disease control. Other treatment options include SSA, PRRT, FOLFOX, and EP. Prospective studies evaluating different treatments effects in NET G3 patients are needed to determine an optimal treatment strategy. [Table: see text]

Abstract Background: Copper deficiency is an established cause of hematological abnormalities, traditionally described in malnourished infants and persons with malabsorption or short bowel syndromes, particularly those requiring long-term parenteral nutrition. With the recent increase in bariatric (weight reduction) surgery, acquired copper deficiency may be increasing in incidence but the diagnosis is frequently delayed. Methods: To outline the natural history of copper deficiency we searched the Mayo Clinic database and our heavy metals laboratory for patients diagnosed with low serum copper during the years 1974–2005. Copper deficiency was defined as a serum level &lt; 0.75 μg/ml. Results: We identified 123 patients with a low serum copper. 77 patients were excluded as the the hypocupremia was either transient or due to other factors such as Wilson’s disease. The remaining 46 patients were all symptomatic. 25 patients had hematological abnormalities, 20 of these patients also had neurological involvement. 5 had isolated hematological manifestations and 21 patients had isolated neurological findings, most commonly myeloneuropathy. 13 presented with anemia and leukopenia, 5 with pancytopenia, 6 with anemia and 1 with isolated neutropenia. In 10 of the 25 cases, a secondary contributing cause for the hematological findings was identified. These included possible anemia of chronic disease (4), renal insufficiency (2), iron deficiency (1), B12 deficiency (1), GI hemorrhage (1), and splenomegaly (1) while copper deficiency was the only identifiable cause in the remaining 15 patients. Hematological parameters at diagnosis are outlined in the table. 15 of the 25 patients with hematological manifestations had a history of GI surgery, including 6 patients who had bariatric surgery. The median time from surgery to diagnosis was 11.5 years (range 8 months - 45 years) and was shorter for bariatric surgery (10 years, range: 8 months - 25 years) than for non-bariatric surgery (18 years, range: 2–45 years). 1 patient had a history of excessive zinc ingestion, 1 had malabsorption secondary to chronic pancreatitis and 1 patient had celiac disease. In 7 cases, no explanation was found. 24 of 25 patients received treatment with oral or intravenous copper, 5 were lost to follow up. In 16 patients the hematologic parameters either improved significantly or normalized, while in the remaining 3 patients there was no improvement. Factors that may explain the lack of response in these patients included splenomegaly (1), renal insufficiency (1) and multiorgan illness (1). Conclusion: Copper deficiency is an increasingly frequent cause of hematological abnormalities, and can manifest with refractory cytopenias with or without associated neurological symptoms. Thrombocytopenia is relatively rare. Previous GI surgery, especially bariatric surgery, appears to be a major causative factor. Most patients will have an improvement in hematological parameters after copper supplementation. Recognition of copper deficiency is therefore assuming greater importance in view of the increasing frequency of bariatric surgery, ease of treatment and potential for irreversible neurological damage if diagnosis is delayed. Hematologic parameters at diagnosis HgB (g/dL) MCV (fL) WBC (x109/L) ANC(x109/L) Plts(x109/L) Median 10.6 99 3.0 1.25 215 Range 7.9-13.6 83.9-114.1 1-5.6 0.18-4.0 54-554

Abstract Background: Copper deficiency is increasingly being diagnosed in adults with malabsorption syndromes, especially following GI surgery such as gastric and bowel resections and bariatric surgery. The most common hematologic manifestations are refractory anemia and neutropenia and patients have been misdiagnosed as having myelodysplasia. Certain findings on bone marrow examination are felt to be characteristic for copper deficiency such as maturation arrest in the myeloid lineage, vacuolization of the erythroid and myeloid precursors and ringed sideroblasts. Methods: We reviewed all cases of copper deficiency diagnosed at the Mayo Clinic from 1974 – 2005. We also reviewed all cases of low serum copper (&lt; 0.75 μg/ml) identified in our heavy metals laboratory. Results: 123 patients with hypocupremia were identified. 77 patients were excluded as the hypocupremia was either transient or due to other factors such as Wilson’s disease. Twenty-five patients had hematologic manifestations, including anemia and leukopenia (13), isolated anemia (6), pancytopenia (5), and isolated neutropenia (1). Eighteen patients had a bone marrow biopsy. We were able to retrieve and review bone marrow slides in 11 cases. The bone marrow examination findings are shown in the table. The marrow cellularity was decreased in four cases. All cases had granulocytic hypoplasia but preserved megakaryopoiesis. Nine cases had relative erythroid hyperplasia. All but one bone marrow had cytoplasmic vacuoles in pronormoblasts and myelocytes. Increased iron within macrophages was seen in 9 cases and increased iron in plasma cells was noted in 8 cases. This was especially prominent in the cases with low peripheral white blood count. Ringed sideroblasts were seen in 4 cases and were more commonly seen in anemic patients. The initial bone marrow examination commonly suggested toxic effect (drugs or alcohol), myelodysplasia or were non-diagnostic. Conclusion: We have described the bone marrow findings in 11 copper deficient patients with abnormal blood counts. None of these patients was suspected of copper deficiency based on the initial marrow examination. The initial impression was commonly toxic effect due to the presence of cytoplasmic vacuolization. Patients with ringed sideroblasts were suspected of having MDS. Copper deficiency should be considered in patients with cytopenias and the described bone marrow findings, especially if there is evidence of malabsorption or a history of GI surgery such as gastric resection or bariatric surgery. Bone marrow findings Patient Cellularity Ery/gran/meg Vacuoles Iron (mø/PC) RS Hgb/Plt WBC/ANC nl: normal, 0: absent, Ery/gran/meg: erythro-/granulo-/megakaryopoiesis, Iron (mø/PC): Iron in macrophages and plasma cells, RS: Ringed sideroblasts 1 ↓ ↑/↓/nl Yes ↑/↑ No 11.3/203 3.2/1.1 2 Nl ↑/↓/nl Yes 0/0 No 11.4/192 5.6/4.0 3 Nl ↑/↓/nl No ↑/0 No 10.6/95 3.0/2.2 4 ↓ ↑/↓/nl Yes ↑/↑ No 13.6/128 4.2/0.92 5 Nl ↑/↓/nl Yes ↑/↑ 10% 9.8/215 1.4/0.6 6 ↓ ↑/↓/nl Yes ↑/↑ No 7.9/292 1.8/0.18 7 Nl ↑/↓/nl Yes ↑/↑ No 10.6/280 2.7/1.4 8 Nl nl/↓/nl Yes ↑/↑ 20% 8.1/330 1.5/0.24 9 Nl ↑/↓/nl Yes ↑/↑ &lt;1% 9.4/252 1.3/0.25 10 ↓ Nl/↓/nl Yes 0/0 No 10.5/167 2.4/1.67 11 Nl ↑/↓/nl Yes ↑/↑ yes 12.5/224 4.2/3.9