Morbidity and Outcomes of Primary Tumor Management in Patients with Widely Metastatic Well-Differentiated Small Bowel Neuroendocrine Tumors

BACKGROUND

The benefit of primary tumor resection in distant metastatic small bowel neuroendocrine tumors (SBNETs) is controversial, with treatment-based morbidity not well-defined. We aimed to determine the impact of primary tumor resection on development of disease-specific complications in patients with metastatic well-differentiated SBNETs.

PATIENTS AND METHODS

A retrospective analysis was performed of patients diagnosed with metastatic well-differentiated jejunal/ileal SBNETs at a single tertiary care cancer center from 1980 to 2016. Outcomes were compared on the basis of treatment selected at diagnosis between patients who underwent initial medical treatment or primary tumor resection.

RESULTS

Among 180 patients, 71 underwent medical management and 109 primary tumor resection. Median follow-up was 116 months. Median event-free survival did not differ between treatment approaches (log-rank p = 0.2). In patients medically managed first, 16/71 (23%) required surgery due to obstruction, perforation, or bleeding. These same complications led to resection at presentation in 31/109 (28%) surgically treated patients. Development of an obstruction from the primary tumor was not associated with disease progression/recurrence (HR 1.14, 95% CI 0.75-1.75) with all patients recovering postoperatively. Ongoing tumor progression requiring secondary laparotomy was associated with worse mortality (HR 7.51, 95% CI 3.3-16.9; p < 0.001) and occurred in 20/109 (18%) primary tumor resection and 7/16 (44%) initially medically treated patients.

CONCLUSIONS

Rates of event-free survival among patients with metastatic SBNETs do not differ on the basis of primary tumor management. The development of an obstruction from the primary tumor was not associated with worse outcomes with all patients salvaged. Regardless of initial treatment selected, patients with metastatic SBNET should be closely followed for early signs of primary tumor complications.

Early-Onset Pancreatic Neuroendocrine Tumors: Clinical Presentation, Pathology Features, and Oncological Outcomes

BACKGROUND

Early-Onset (EO) pancreatic neuroendocrine tumor (PanNET) is a rare disease, but whether it is clinically different from late-onset (LO) PanNET is unknown. Our study aimed to evaluate clinical differences and disease outcomes between EO-PanNET and LO-PanNET and to compare sporadic EO-PanNET with those with a hereditary syndrome.

METHODS

Patients with localized PanNET who underwent pancreatectomy at Memorial Sloan Kettering between 2000 and 2017 were identified. Those with metastatic disease and poorly differentiated tumors were excluded. EO-PanNET was defined as <50 and LO-PanNET >50 years of age at the time of diagnosis. Family history and clinical and pathology characteristics were recorded.

RESULTS

Overall 383 patients were included, 107 (27.9%) with EO-PanNET. Compared with LO-PanNET, EO-PanNET were more likely to have a hereditary syndrome (2.2% vs. 16%, P <0.001) but had similar pathology features such as tumor grade ( P =0.6), size (2.2 Vs. 2.3 cm, P =0.5) and stageof disease ( P =0.8). Among patients with EO-PanNET, those with hereditary syndrome had more frequently a multifocal disease (65% vs. 3.3%, P <0.001). With a median follow-up of 70 months (range 0-238), the 5-year cumulative incidence of recurrence after curative surgery was 19% (95% CI 12%-28%) and 17% (95% CI 13%-23%), in EO-PanNET and LO-PanNET ( P =0.3). Five-year disease-specific survival was 99% (95% CI 98%-100%) with no difference with respect to PanNET onset time ( P =0.26).

CONCLUSIONS

In this surgical cohort, we found that EO-PanNET is associated with hereditary syndromes but has pathologic characteristics and oncological outcomes similar to LO-PanNET. These findings suggest that patients with EO-PanNET can be managed similarly to those with LO-PanNET.

Recurring Pancreatic Neuroendocrine Tumor: Timing and Pattern of Recurrence and Current Treatment

OBJECTIVE

The objective of this study was to describe the pattern of recurrence, treatments received, as well the oncological outcomes, of pancreatic neuroendocrine tumors (PanNETs) following curative surgery.

BACKGROUND

PanNETs recur in 10% to 15% of cases following surgery. Information on the natural history and management of recurring disease is lacking.

MATERIALS AND METHODS

Patients with PanNET that underwent curative surgery at 4 institutions between 2000 and 2019 were identified. Patients with poorly differentiated tumors, unknown tumor grade and differentiation, hereditary syndromes, unknown margin or R2 status, metastatic, and those that had neoadjuvant treatment or perioperative mortality were excluded. Clinical variables were assessed including first site of recurrence, treatment received, and survival outcomes.

RESULTS

A total of 1402 patients were included: 957 (74%) had grade 1, 322 (25%) had grade 2, and 13 (1%) had grade 3 tumors. Median follow-up was 4.8 years (interquartile range: 2-8.2 years). Cumulative incidence of recurrence at 5 years was 13% (95% CI: 11%-15.2%) for distant disease, 1.4% (95% CI: 0.8%-2.3%) for locoregional recurrence, and 0.8% (95% CI: 0.4%-1.5%) for abdominal nodal recurrence. Patients who recurred had 2.89 increased risk of death (95% CI: 2-4.1) as compared with patients who did not recur. Therapy postrecurrence included: somatostatin analogs in 111 (61.0%), targeted therapies in 48 (26.4%), liver-directed therapies in 61 (33.5%), peptide receptor radionuclide therapy in 30 (16.5%), and surgery in 46 (25.3%) patients. Multiple treatments were used in 103 (57%) cases. After the first recurrence, 5-year overall survival was 74.6% (95% CI: 67.4%-82.5%).

CONCLUSIONS

Recurrence following surgery is infrequent but reduces survival. Most recurrences are distant and managed with multiple therapies. Prospective studies are needed to establish strategies for surveillance and the sequence of treatment to control the disease and prolong survival.

Consensus report of the 2021 National Cancer Institute neuroendocrine tumor clinical trials planning meeting

Important progress has been made over the last decade in the classification, imaging, and treatment of neuroendocrine neoplasm (NENs), with several new agents approved for use. Although the treatment options available for patients with well-differentiated neuroendocrine tumors (NETs) have greatly expanded, the rapidly changing landscape has presented several unanswered questions about how best to optimize, sequence, and individualize therapy. Perhaps the most important development over the last decade has been the approval of 177Lu-DOTATATE for treatment of gastroenteropancreatic-NETs, raising questions around optimal sequencing of peptide receptor radionuclide therapy (PRRT) relative to other therapeutic options, the role of re-treatment with PRRT, and whether PRRT can be further optimized through use of dosimetry among other approaches. The NET Task Force of the National Cancer Institute GI Steering Committee convened a clinical trial planning meeting in 2021 with multidisciplinary experts from academia, the federal government, industry, and patient advocates to develop NET clinical trials in the era of PRRT. Key clinical trial recommendations for development included 1) PRRT re-treatment, 2) PRRT and immunotherapy combinations, 3) PRRT and DNA damage repair inhibitor combinations, 4) treatment for liver-dominant disease, 5) treatment for PRRT-resistant disease, and 6) dosimetry-modified PRRT.

Randomized Study of Temozolomide or Temozolomide and Capecitabine in Patients With Advanced Pancreatic Neuroendocrine Tumors (ECOG-ACRIN E2211)

PURPOSE

Patients with advanced pancreatic neuroendocrine tumors (NETs) have few treatment options that yield objective responses. Retrospective and small prospective studies suggest that capecitabine and temozolomide are associated with high response rates (RRs) and long progression-free survival (PFS).

PATIENTS AND METHODS

E2211 was a multicenter, randomized, phase II trial comparing temozolomide versus capecitabine/temozolomide in patients with advanced low-grade or intermediate-grade pancreatic NETs. Key eligibility criteria included progression within the preceding 12 months and no prior temozolomide, dimethyl-triazeno-imidazole-carboxamide or dacarbazine, capecitabine or fluorouracil. The primary end point was PFS; secondary endpoints were overall survival, RR, safety, and methylguanine methyltransferase (MGMT) by immunohistochemistry and promoter methylation.

RESULTS

A total of 144 patients were enrolled between April 2013 and March 2016 to temozolomide (n = 72) or capecitabine and temozolomide (n = 72); the primary analysis population included 133 eligible patients. At the scheduled interim analysis in January 2018, the median PFS was 14.4 months for temozolomide versus 22.7 months for capecitabine/temozolomide (hazard ratio = 0.58), which was sufficient to reject the null hypothesis for the primary end point (stratified log-rank P = .022). In the final analysis (May 2021), the median overall survival was 53.8 months for temozolomide and 58.7 months for capecitabine/temozolomide (hazard ratio = 0.82, P = .42). MGMT deficiency was associated with response.

CONCLUSION

The combination of capecitabine/temozolomide was associated with a significant improvement in PFS compared with temozolomide alone in patients with advanced pancreatic NETs. The median PFS and RR observed with capecitabine/temozolomide are the highest reported in a randomized study for pancreatic NETs. MGMT deficiency was associated with response, and although routine MGMT testing is not recommended, it can be considered for select patients in need of objective response (ClinicalTrials.gov identifier: NCT01824875).

Analysis of a Remote Monitoring Program for Symptoms Among Adults With Cancer Receiving Antineoplastic Therapy

IMPORTANCE

Electronic patient-reported outcomes (ePROs) may have the potential to improve cancer care delivery by enhancing patient quality of life, reducing acute care visits, and extending overall survival. However, the optimal cadence of ePRO assessments is unknown.

OBJECTIVE

To determine patient response preferences and the clinical value associated with a daily cadence for ePROs for patients receiving antineoplastic treatment.

DESIGN, SETTING, AND PARTICIPANTS

This quality improvement study of adult patients undergoing antineoplastic treatment assessed a remote monitoring program using ePROs that was developed to manage cancer therapy-related symptoms. ePRO data submitted between October 16, 2018 to February 29, 2020, from a single regional site within the Memorial Sloan Kettering Cancer Center network were included. Data were analyzed from April 2020 to January 2022.

EXPOSURE

While undergoing active treatment, patients received a daily ePRO assessment that, based on patient responses, generated yellow (moderate) or red (severe) symptom alerts that were sent to clinicians.

MAIN OUTCOMES AND MEASURES

The main outcomes assessed included patient response rate, symptom alert frequency, and an analysis of the clinical value of daily ePROs.

RESULTS

A total of 217 patients (median [range] age, 66 [31-92] years; 103 [47.5%] women and 114 [52.5%] men) initiating antineoplastic therapy at high risk for symptoms were monitored for a median (range) of 91 (2-369) days. Most patients had thoracic (59 patients [27.2%]), head and neck (48 patients [22.1%]), or gastrointestinal (43 patients [19.8%]) malignant neoplasms. Of 14 603 unique symptom assessments completed, 7349 (50.3%) generated red or yellow symptom alerts. Symptoms commonly generating alerts included pain (665 assessments [23.0%]) and functional status (465 assessments [16.1%]). Most assessments (8438 assessments [57.8%]) were completed at home during regular clinic hours (ie, 9 am-5 pm), with higher response rates on weekdays (58.4%; 95% CI, 57.5%-59.5%) than on weekend days (51.3%; 95% CI, 49.5%-53.1%). Importantly, 284 of 630 unique red alerts (45.1%) surfaced without a prior yellow alert for the same symptom within the prior 7 days; symptom severity fluctuated over the course of a week, and symptom assessments generating a red alert were followed by an acute care visit within 7 days 8.7% of the time compared with 2.9% for assessments without a red alert.

CONCLUSIONS AND RELEVANCE

These findings suggest that daily ePRO assessments were associated with increased insight into symptom management in patients undergoing antineoplastic treatment and symptom alerts were associated with risk of acute care.

Oncology Patients' Perspectives on Remote Patient Monitoring for COVID-19

PURPOSE

Oncology patients are vulnerable to adverse outcomes associated with COVID-19, and clinical deterioration must be identified early. Several institutions launched remote patient monitoring programs (RPMPs) to care for patients with COVID-19. We describe patients' perspectives on a COVID-19 RPMP at a National Comprehensive Cancer Center.

METHODS

Patients who tested positive for COVID-19 were eligible. Enrolled patients received a daily electronic COVID-19 symptom assessment, and a subset of high-risk patients also received a pulse oximeter. Monitoring was provided by a centralized team and was discontinued 14 days after a patient's positive test result and following 3 days without worsening symptoms. Patients who completed at least one assessment and exited the program were sent a patient engagement survey to evaluate the patient's experience with digital monitoring for COVID-19.

RESULTS

The survey was distributed to 491 patients, and 257 responded (52% completion rate). The net promoter score was 85%. Most patients agreed that the RPMP was worthwhile, enabled better management of their COVID-19 symptoms, made them feel more connected to their healthcare team, and helped prevent emergency room visits. Identified themes regarding patient-perceived value of a RPMP included (1) security: a clinical safety net; (2) connection: a link to their clinical team during a period of isolation; and (3) empowerment: an education on the virus and symptom management.

CONCLUSION

RPMPs are perceived to be of value to oncology patients with COVID-19. Policymakers should consider how these programs can be reimbursed to keep vulnerable patients at home and out of the acute care setting.

Platinum-Based Treatment for Well- and Poorly Differentiated Pancreatic Neuroendocrine Neoplasms

OBJECTIVES

Pancreatic neuroendocrine neoplasms include well-differentiated tumors (PanNETs) and poorly differentiated carcinomas (PanNECs). Previous reports suggested a role for platinum-based therapy largely in PanNEC. We sought to investigate the role of platinum-based therapy in pancreatic neuroendocrine neoplasms regardless of tumor grade and differentiation.

METHODS

Patients with pancreatic neuroendocrine neoplasms treated with platinum-based therapy at Memorial Sloan Kettering (1994-2016) and Verona University Hospital (2008-2016) were retrospectively identified. Response to treatment by RECIST v1.1, overall survival, and progression-free survival were defined. Among patients with available tissue, DAXX, ATRX, Rb, and p53 expression was evaluated to support the histologic grade of differentiation.

RESULTS

Fifty PanNETs, 29 PanNECs, and 22 high-grade tumors with undeterminable differentiation were included. No patients achieved complete response. Overall rate of partial response was 31%, 41% for PanNEC, and 20% for PanNETs. Among PanNETs, partial response was achieved in 33% of G1 (2/6), 10% of G2 (2/19), and 24% of G3 (6/25) tumors. Median overall survival was 29.3 months for PanNETs and 10.9 months for PanNEC (P < 0.001). There was no significant difference in median progression-free survival (P = 0.2).

CONCLUSIONS

Platinum-based therapies demonstrated increased activity in PanNEC; however, promising efficacy was also observed in PanNETs, irrespective of grade.

Characterization and Clinical Outcomes of DNA Mismatch Repair-deficient Small Bowel Adenocarcinoma

PURPOSE

The prevalence and clinical characteristics of small bowel adenocarcinomas (SBA) in the setting of Lynch syndrome have not been well studied. We characterized SBA according to DNA mismatch repair and/or microsatellite instability (MMR/MSI) and germline mutation status and compared clinical outcomes.

EXPERIMENTAL DESIGN

A single-institution review identified 100 SBAs. Tumors were evaluated for MSI via MSIsensor and/or corresponding MMR protein expression via IHC staining. Germline DNA was analyzed for mutations in known cancer predisposition genes, including MMR (MLH1, MSH2, MSH6, PMS2, and EPCAM). Clinical variables were correlated with MMR/MSI status.

RESULTS

Twenty-six percent (26/100; 95% confidence interval, 18.4-35.4) of SBAs exhibited MMR deficiency (MMR-D). Lynch syndrome prevalence was 10% overall and 38.5% among MMR-D SBAs. Median age at SBA diagnosis was similar in non-Lynch syndrome MMR-D versus MMR-proficient (MMR-P) SBAs (65 vs. 61; P = 0.75), but significantly younger in Lynch syndrome (47.5 vs. 61; P = 0.03). The prevalence of synchronous/metachronous cancers was 9% (6/67) in MMR-P versus 34.6% (9/26) in MMR-D SBA, with 66.7% (6/9) of these in Lynch syndrome (P = 0.0002). In the MMR-P group, 52.2% (35/67) of patients presented with metastatic disease, compared with 23.1% (6/26) in the MMR-D group (P = 0.008). In MMR-P stage I/II patients, 88.2% (15/17) recurred, compared with 18.2% (2/11) in the MMR-D group (P = 0.0002).

CONCLUSIONS

When compared with MMR-P SBA, MMR-D SBA was associated with earlier stage disease and lower recurrence rates, similar to observations in colorectal cancer. With a 38.5% prevalence in MMR-D SBA, germline Lynch syndrome testing in MMR-D SBA is warranted.

Building a Clinically Relevant Risk Model: Predicting Risk of a Potentially Preventable Acute Care Visit for Patients Starting Antineoplastic Treatment

PURPOSE

To create a risk prediction model that identifies patients at high risk for a potentially preventable acute care visit (PPACV).

PATIENTS AND METHODS

We developed a risk model that used electronic medical record data from initial visit to first antineoplastic administration for new patients at Memorial Sloan Kettering Cancer Center from January 2014 to September 2018. The final time-weighted least absolute shrinkage and selection operator model was chosen on the basis of clinical and statistical significance. The model was refined to predict risk on the basis of 270 clinically relevant data features spanning sociodemographics, malignancy and treatment characteristics, laboratory results, medical and social history, medications, and prior acute care encounters. The binary dependent variable was occurrence of a PPACV within the first 6 months of treatment. There were 8,067 observations for new-start antineoplastic therapy in our training set, 1,211 in the validation set, and 1,294 in the testing set.

RESULTS

A total of 3,727 patients experienced a PPACV within 6 months of treatment start. Specific features that determined risk were surfaced in a web application, riskExplorer, to enable clinician review of patient-specific risk. The positive predictive value of a PPACV among patients in the top quartile of model risk was 42%. This quartile accounted for 35% of patients with PPACVs and 51% of potentially preventable inpatient bed days. The model C-statistic was 0.65.

CONCLUSION

Our clinically relevant model identified the patients responsible for 35% of PPACVs and more than half of the inpatient beds used by the cohort. Additional research is needed to determine whether targeting these high-risk patients with symptom management interventions could improve care delivery by reducing PPACVs.

Abstract LB-003: OncoMatch: Unbiased, quantitative assessment of cancer model fidelity for drug sensitivity and mechanism of action elucidation

Quantitative metrics to objectively assess the fidelity of cancer models, such as cell lines, organoids, or patient-derived xenografts (PDXs), remain elusive, with histological criteria or the presence of specific mutations often used as driving principles. However, focusing on individual mutations inevitably ignores the effect of a large complement of additional, model-specific genetic and epigenetic events. As a result, effective model fidelity assessment is best performed a posteriori, for instance, by determining whether dependencies identified in a specific tumor model (e.g., a cell line or organoid) are recapitulated in vivo in PDXs or in patients, via pre-clinical or clinical trials. Unfortunately, such an approach is inefficient and time-consuming, creating an urgent need for methodologies capable of effectively and quantitatively assessing model fidelity a priori.

This unmet need motivated us to develop and test a quantitative, molecular-level framework (OncoMatch), to assess the fidelity of a given tumor model in the context of a specific biological question, and in particular for addressing issues of drug sensitivity. We addressed this challenge by integrating two independent computational metrics to assess: (a) conservation of regulatory networks inferred from patient-derived samples in a model of interest, and; (b) overlap of master regulator (MR) proteins–i.e., proteins representing the mechanistic determinants of the transcriptional state associated with the phenotype of interest–as inferred from patient-derived and model-derived samples.

We show that these molecular-level criteria can effectively identify cell lines that recapitulate patient-specific drug mechanism of action and drug sensitivity, independent of histological consideration. By leveraging gene expression profiles of drug-perturbations in primary cells and explants derived from gastroenteropancreatic-neuroendocrine tumor (GEP-NET) patients, we show that H-STS, an EBV-immortalized lymphoblastoid cell line, represents a high-fidelity model for the assessment of drug mechanism of action and drug sensitivity in these tumors. In particular, our analysis shows highly significant conservation of drug mechanism of action for 60 of 95 profiled drugs (63%, p &lt; 10-10, Bonferroni's corrected), and higher conservation among drugs exhibiting greater bioactivity in this context. This rate is comparable and, in fact higher than what is achieved using tumor-type-matched cell line pairs representative of glioma, pancreatic and prostate carcinoma, and dramatically higher than the conservation observed between unrelated models, which we used as negative controls.

Based on this systematic analysis, OncoMatch represents a valuable addition to our repertoire of tools for prioritizing cell lines, organoids and patient-derived xenograft models as high-fidelity human cancer models. We provide comprehensive prioritization of 921 cell lines as potential high-fidelity models for 10,024 human tumor samples in TCGA. This represents an actionable resource to guide selection of cell line models for specific drug mechanism of action and drug sensitivity studies.

Citation Format: Mariano J. Alvarez, Yan Pengrong, Mary L. Alpaugh, Michaela Bowden, Ewa T. Sicinska, Chensheng W. Zhou, Charles Karan, Ronald B. Realubit, Prabhjot S. Mundi, Adina Grunn, Jager Dirk, John A. Chabot, Antonio T. Fojo, Paul E. Oberstein, Hanina Hibshoosh, Jeffrey W. Milsom, Matthew H. Kulke, Massimo Loda, Gabriela Chiosis, Diane L. Reidy-Lagunes, Andrea Califano. OncoMatch: Unbiased, quantitative assessment of cancer model fidelity for drug sensitivity and mechanism of action elucidation [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-003.

The North American Neuroendocrine Tumor Society Consensus Guidelines for Surveillance and Medical Management of Pancreatic Neuroendocrine Tumors

This article is the result of the North American Neuroendocrine Tumor Society consensus conference on the medical management of pancreatic neuroendocrine tumors from July 19 to 20, 2018. The guidelines panel consisted of medical oncologists, pathologists, gastroenterologists, endocrinologists, and radiologists. The panel reviewed a series of questions regarding the medical management of patients with pancreatic neuroendocrine tumors as well as questions regarding surveillance after resection. The available literature was reviewed for each of the question and panel members voted on controversial topics, and the recommendations were included in a document circulated to all panel members for a final approval.

InSight Care Pilot Program: Redefining Seeing a Patient

PURPOSE

Early detection and management of symptoms in patients with cancer improves outcomes. However, the optimal approach to symptom monitoring and management is unknown. InSight Care is a mobile health intervention that captures symptom data and facilitates patient-provider communication to mitigate symptom escalation.

PATIENTS AND METHODS

Patients initiating antineoplastic treatment at a Memorial Sloan Kettering regional location were eligible. Technology supporting the program included the following: a predictive model that identified patient risk for a potentially preventable acute care visit; a secure patient portal enabling communication, televisits, and daily delivery of patient symptom assessments; alerts for concerning symptoms; and a symptom-trending application. The main outcomes of the pilot were feasibility and acceptability evaluated through enrollment and response rates and symptom alerts, and perceived value evaluated on the basis of qualitative patient and provider interviews.

RESULTS

The pilot program enrolled 100 high-risk patients with solid tumors and lymphoma (29% of new treatment starts v goal of 25%). Over 6 months of follow-up, the daily symptom assessment response rate was 56% (the goal was 50%), and 93% of patients generated a severe symptom alert. Patients and providers perceived value in the program, and archetypes were developed for program improvement. Enrolled patients were less likely to use acute care than were other high-risk patients.

CONCLUSION

InSight Care was feasible and holds the potential to improve patient care and decrease facility-based care. Future work should focus on optimizing the cadence of patient assessments, the workforce supporting remote symptom management, and the return of symptom data to patients and clinical teams.

SUN-911 Immunotherapy Use in Adrenocortical Carcinoma with Encouraging Results- a Case Report

Adrenocortical carcinoma (ACC) is a rare cancer with a very poor prognosis with median survival of around 17 months. We present a patient with metastatic ACC in whom the response to PD1 inhibitor pembrolizumab has been promising.

Case report: A Caucasian female patient presented at the age of 19 y with weight gain, hypertension, moon facies, supraclavicular fullness and increased hair growth on her upper back. Serum potassium concentration was 2.6 mmol/l, cortisol was 46 mcg/dL (nl = 3-12mcg/dL), and plasma ACTH concentration was &lt; 5 pg/ml (nl = 6-58pg/ml). CT abdomen revealed a 5.4 cm right adrenal mass. For ACTH-independent Cushing’s Syndrome, she underwent right adrenalectomy within 1 week of presentation. Pathology revealed a 6.5 cm ACC with negative margins, with sinusoidal invasion, but no vascular or capsular invasion. Mitosis rate was 15-20/HPF with atypical mitotic figures. Immunohistochemistry showed no loss of expression of mismatch repair gene products associated with microsatellite instability. She was unable to tolerate mitotane. Genetic analysis was negative for TP53 mutation, and she underwent radiation to the adrenal bed within 6 months following adrenalectomy. She remained without biochemical or structural evidence of disease recurrence until 2.5 years following adrenalectomy, when AM cortisol was 6 mcg/dL (nl &lt; 1.8) after 1 mg and after 2 mg of dexamethasone the previous evening. CT scan of the pelvis, abdomen, and chest revealed 5 solid masses scattered within the lungs. The largest of these being 2.3 cm and 2 cm, and the other 3 being approximately 1 cm. Fine needle aspiration biopsy of the lung lesion revealed ACC metastases. Immunotherapy with pembrolizumab 200 mg every 3 weeks was initiated and continued for 2 years, with a side effect being grade 1 diarrhea. At 1 year after initiating pembrolizumab, she developed primary adrenal insufficiency that is being treated with 0.1 mg/d of fludrocortisone and low dose glucocorticoid replacement (hydrocortisone: 10mg in the morning and 5 mg in the evening), to avoid immune suppression. Pulmonary nodules decreased in size to 6 mm over the 2 years of pembrolizumab therapy and remained stable in size 1 year following completion of pembrolizumab therapy at which time the early morning serum cortisol concentration remained undetectable with a plasma ACTH concentration of 1177 pg/ml (nl = 6-50 pg/ml). In summary, this patient with ACC with normal mismatch repair gene expression demonstrated both structural and biochemical responses to 2 years of pembrolizumab therapy. The major side effect has been primary adrenal insufficiency. The biochemical and structural responses have been durable for 1 year after completion of pembrolizumab therapy.

Conclusion: This patient with microsatellite stable ACC has had a 36-month response to pembrolizumab.

Mismatch Repair-Deficient Rectal Cancer and Resistance to Neoadjuvant Chemotherapy

PURPOSE

Evaluate response of mismatch repair-deficient (dMMR) rectal cancer to neoadjuvant chemotherapy.

EXPERIMENTAL DESIGN

dMMR rectal tumors at Memorial Sloan Kettering Cancer Center (New York, NY) were retrospectively reviewed for characteristics, treatment, and outcomes. Fifty patients with dMMR rectal cancer were identified by IHC and/or microsatellite instability analysis, with initial treatment response compared with a matched MMR-proficient (pMMR) rectal cancer cohort. Germline and somatic mutation analyses were evaluated. Patient-derived dMMR rectal tumoroids were assessed for chemotherapy sensitivity.

RESULTS

Of 21 patients receiving neoadjuvant chemotherapy (fluorouracil/oxaliplatin), six (29%) had progression of disease. In comparison, no progression was noted in 63 pMMR rectal tumors (P = 0.0001). Rectal cancer dMMR tumoroids reflected this resistance to chemotherapy. No genomic predictors of chemotherapy response were identified. Of 16 patients receiving chemoradiation, 13 (93%) experienced tumor downstaging; one patient had stable disease, comparable with 48 pMMR rectal cancers. Of 13 patients undergoing surgery, 12 (92%) had early-stage disease. Forty-two (84%) of the 50 patients tested positive for Lynch syndrome with enrichment of germline MSH2 and MSH6 mutations when compared with 193 patients with Lynch syndrome-associated colon cancer (MSH2, 57% vs 36%; MSH6, 17% vs 9%; P < 0.003).

CONCLUSIONS

Over one-fourth of dMMR rectal tumors treated with neoadjuvant chemotherapy exhibited disease progression. Conversely, dMMR rectal tumors were sensitive to chemoradiation. MMR status should be performed upfront in all locally advanced rectal tumors with careful monitoring for response on neoadjuvant chemotherapy and genetic testing for Lynch syndrome in patients with dMMR rectal cancer.

PD-1 Blockade in Advanced Adrenocortical Carcinoma

PURPOSE

Adrenocortical carcinomas (ACC) are rare and aggressive malignancies with limited treatment options. This study was undertaken to evaluate the immunogenicity of ACC.

PATIENTS AND METHODS

Patients with advanced ACC were enrolled in a phase II study to evaluate the clinical activity of pembrolizumab 200 mg every 3 weeks, without restriction on prior therapy. The primary end point was objective response rate. Efficacy was correlated with tumor programmed death-ligand 1 expression, microsatellite-high and/or mismatch repair deficient (MSI-H/MMR-D) status, and somatic and germline genomic correlates.

RESULTS

We enrolled 39 patients with advanced ACC and herein report after a median follow-up of 17.8 months (range, 5.4 months to 34.7 months). The objective response rate to pembrolizumab was 23% (nine patients; 95% CI, 11% to 39%), and the disease control rate was 52% (16 patients; 95% CI, 33% to 69%). The median duration of response was not reached (lower 95% CI, 4.1 months). Two of six patients with MSI-H/MMR-D tumors responded. The other seven patients with objective responses had microsatellite stable tumors. The median progression-free survival was 2.1 months (95% CI, 2.0 months to 10.7 months), and the median overall survival was 24.9 months (95% CI, 4.2 months to not reached). Thirteen percent of patients (n = 5) had treatment-related grade 3 or 4 adverse events. Tumor programmed death-ligand 1 expression and MSI-H/MMR-D status were not associated with objective response.

CONCLUSION

MSI-H/MMR-D tumors, for which pembrolizumab is a standard therapy, are more common in ACC than has been recognized. In advanced ACC that is microsatellite stable, pembrolizumab provided clinically meaningful and durable antitumor activity with a manageable safety profile.

Induction Chemotherapy Reduces Patient-reported Toxicities During Neoadjuvant Chemoradiation with Intensity Modulated Radiotherapy for Rectal Cancer

BACKGROUND

Initial treatment with either neoadjuvant chemoradiation (CRT) or induction FOLFOX (5-Fluorouracil, leucovorin, and oxaliplatin) chemotherapy followed by CRT is considered standard treatment for locally advanced rectal cancer. We compared patient-reported outcomes (PRO) during CRT in patients who had received induction chemotherapy versus those who did not.

PATIENTS AND METHODS

We reviewed records of patients with locally advanced rectal cancer who were treated with CRT between September 2009 and October 2014, and who had completed ≥ 4 PRO assessments during treatment. Clinician- and patient-reported toxicities were collected each week during treatment. We fit binomial generalized linear models to maximum toxicity scores across all patients' visits.

RESULTS

Of 123 patients with ≥ 4 PRO assessments, 87 (71%) patients reported a clinically meaningful PRO score of 3 or higher for diarrhea, and 91 (74%) patients reported a PRO score of ≥ 3 for urgency, during 1 or more weeks of treatment, corresponding to 'very frequent' or worse. Of 116 patients who had also completed ≥ 4 clinician-reported assessments for descriptive analysis, clinically significant diarrhea (Common Terminology Criteria for Adverse Events grade ≥ 2) was reported in 9% of patients, and grade 2 proctitis and cystitis were reported in 20% and 4%, respectively. Eighty-four (68%) patients had undergone induction chemotherapy prior to CRT. Patients who received induction chemotherapy had 68% lower odds of experiencing significant urgency (odds ratio [OR], 0.32; 95% confidence interval [CI], 0.11-0.95; P = .04), 76% lower odds of bleeding (OR, 0.24; 95% CI, 0.1-0.62; P < .01), and 75% lower odds of tenesmus (OR, 0.25; 95% CI, 0.11-0.6; P < .01) versus those treated with upfront CRT.

CONCLUSION

Based on PROs, a high proportion of patients experienced clinically significant symptoms during pelvic CRT, with diarrhea and urgency being most commonly reported. This appears to be under-reported on clinician-reported assessments. Delivery of induction chemotherapy was associated with lower odds of experiencing urgency, bleeding, and tenesmus on PROs during subsequent CRT, with no significant impact on diarrhea and rectal pain.

Complete Responses to Mitotane in Metastatic Adrenocortical Carcinoma-A New Look at an Old Drug

PURPOSE

Based largely on reports that predate modern reporting standards, mitotane has been considered a systemic treatment option for both hormone control and antitumor control of metastatic adrenocortical cancer (ACC), although the therapeutic window is narrow.

METHODS

We searched electronic medical records to identify patients with metastatic ACC treated and prescribed single-agent mitotane at Memorial Sloan Kettering Cancer Center from March 15, 1989-September 18, 2015. Reference radiologists reviewed all imaging and determined efficacy according to Response Evaluation Criteria in Solid Tumors 1.1. Patient demographics, toxicities, and treatment outcomes were reviewed. Next-generation sequencing was performed in selected cases.

RESULTS

Thirty-six patients were identified. The mean age was 54 and 50% had functional tumors. Grade 3 or greater toxicities were documented in 16 out of 36 patients (44%) and 17% had documented long term adrenal insufficiency. Progression of the disease as the best response occurred in 30 out of 36 patients (83%) and one patient (3%) experienced clinical progression. Three patients achieved a complete response (CR) (8%), one patient achieved a partial response (3%), and one patient (3%) had stable disease after slow disease progression prior to initiation of therapy (durable for 6 months). All responders had nonfunctional tumors. Next-generation sequencing in two of the three CR patients was performed and failed to identify any novel alterations.

CONCLUSION

In this retrospective series, mitotane had a low response rate and low tumor control rate; however, a disproportionately high complete response rate suggested it should be used in selected individuals. Adrenal insufficiency is common with mitotane use and aggressive treatment with steroid supplementation should be considered when appropriate to avoid excess toxicities. Biomarkers are desperately needed to further define this disease.

IMPLICATIONS FOR PRACTICE

This is the first objective report of single-agent mitotane using modern objective criteria. Although the vast majority of patients did not respond (and toxicity was high), we identified a remarkable 8% complete response rate (i.e. cure) in biopsy proven stage IV adrenocortical cancer patients. Biomarkers are desperately needed for this rare disease.

Reliable Detection of Mismatch Repair Deficiency in Colorectal Cancers Using Mutational Load in Next-Generation Sequencing Panels

PURPOSE

Tumor screening for Lynch syndrome is recommended in all or most patients with colorectal cancer (CRC). In metastatic CRC, sequencing of RAS/BRAF is necessary to guide clinical management. We hypothesized that a next-generation sequencing (NGS) panel that identifies RAS/BRAF and other actionable mutations could also reliably identify tumors with DNA mismatch repair protein deficiency (MMR-D) on the basis of increased mutational load.

METHODS

We identified all CRCs that underwent genomic mutation profiling with a custom NGS assay (MSK-IMPACT) between March 2014 and July 2015. Tumor mutational load, with exclusion of copy number changes, was determined for each case and compared with MMR status as determined by routine immunohistochemistry.

RESULTS

Tumors from 224 patients with unique CRC analyzed for MMR status also underwent MSK-IMPACT. Thirteen percent (n = 28) exhibited MMR-D by immunohistochemistry. Using the 341-gene assay, 100% of the 193 tumors with < 20 mutations were MMR-proficient. Of 31 tumors with ≥ 20 mutations, 28 (90%) were MMR-D. The three remaining tumors were easily identified as being distinct from the MMR-D tumors with > 150 mutations each. Each of these tumors harbored the P286R hotspot POLE mutation consistent with the ultramutator phenotype. Among MMR-D tumors, the median number of mutations was 50 (range, 20 to 90) compared with six (range, 0 to 17) in MMR-proficient/POLE wild-type tumors (P < .001). With a mutational load cutoff of ≥ 20 and < 150 for MMR-D detection, sensitivity and specificity were both 1.0 (95% CI, 0.93 to 1.0).

CONCLUSION

A cutoff for mutational load can be identified via multigene NGS tumor profiling, which provides a highly accurate means of screening for MMR-D in the same assay that is used for tumor genotyping.

Observation versus Resection for Small Asymptomatic Pancreatic Neuroendocrine Tumors: A Matched Case-Control Study

OBJECTIVE

To analyze the natural history of small asymptomatic pancreatic neuroendocrine tumors (PanNET) and to present a matched comparison between groups who underwent either initial observation or resection. Management approach for small PanNET is uncertain.

METHODS

Incidentally discovered, sporadic, small (<3 cm), stage I-II PanNET were analyzed retrospectively between 1993 and 2013. Diagnosis was determined either by pathology or imaging characteristics. Intention-to-treat analysis was applied.

RESULTS

A total of 464 patients were reviewed. Observation was recommended for 104 patients (observation group), and these patients were matched to 77 patients in the resection group based on tumor size at initial imaging. The observation group was significantly older (median 63 vs. 59 years, p = 0.04) and tended towards shorter follow-up (44 vs. 57 months, p = 0.06). Within the observation group, 26 of the 104 patients (25 %) underwent subsequent tumor resection after a median observation interval of 30 months (range 7-135). At the time of last follow-up of the observation group, the median tumor size had not changed (1.2 cm, p = 0.7), and no patient had developed evidence of metastases. Within the resection group, low-grade (G1) pathology was recorded in 72 (95 %) tumors and 5 (6 %) developed a recurrence, which occurred after a median of 5.1 (range 2.9-8.1) years. No patient in either group died from disease. Death from other causes occurred in 11 of 181 (6 %) patients.

CONCLUSIONS

In this study, no patient who was initially observed developed metastases or died from disease after a median follow-up of 44 months. Observation for stable, small, incidentally discovered PanNET is reasonable in selected patients.

New and Emerging Treatment Options for Gastroenteropancreatic Neuroendocrine Tumors

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are rare, generally indolent neoplasms that can arise throughout the gastrointestinal system. Some GEP-NETs, known as functional, secrete hormones that can lead to a complex of symptoms. Classical carcinoid syndrome is associated with flushing, diarrhea, bronchospasm, and symptoms of valvular heart disease. GEP-NETs are classified according to the primary tumor site, functionality of the disease, and histology. Treatment is guided by the resectability of the tumor, the location and extent of metastases, and the presence of clinical symptoms. Typically, first-line treatment of patients with unresectable disease includes the use of somatostatin analogs, such as octreotide LAR depot or lanreotide depot/autogel, which was recently approved by the US Food and Drug Administration for treatment of GEP-NETs. Somatostatin analogs can improve the severe diarrhea/flushing episodes that may be associated with metastatic carcinoid tumors. For patients with pancreatic NETs, additional approved treatment options include the targeted agents everolimus and sunitinib, which have demonstrated antitumor activity. Chemotherapy may also have a selective role, particularly in pancreatic NETs. Localized approaches, including cytoreductive surgery, hepatic arterial embolization, and ablative therapies, may be used for palliative treatment in patients with liver metastases.

Neoadjuvant chemotherapy first, followed by chemoradiation and then surgery, in the management of locally advanced rectal cancer

Standard therapy for locally advanced rectal cancer (LARC) is preoperative chemoradiotherapy and postoperative chemotherapy. At Memorial Sloan-Kettering Cancer Center (MSKCC) the authors began offering FOLFOX (5-fluorouracil, leucovorin, and oxaliplatin) as initial treatment for patients with high-risk LARC to target micrometastases while treating the primary tumor. The purpose of this study is to report the safety and efficacy of initial FOLFOX given before chemoradiotherapy on tumor downsizing and pathologic complete response (pathCR) in LARC. The records of patients with stage II/III rectal cancer treated at MSKCC between 2007 and 2012 were reviewed. Of approximately 300 patients with LARC treated at MSKCC, 61 received FOLFOX as initial therapy. Of these 61 patients, 57 received induction FOLFOX (median 7 cycles) followed by chemoradiation, and 4 experienced an excellent response, declined chemoradiation, and underwent total mesorectal excision (TME). Twelve of the 61 patients did not undergo TME: 9 had a complete clinical response (CCR), 1 declined despite persistent tumor, 1 declined because of comorbidities, and 1 developed metastatic disease. Among the 61 patients receiving initial FOLFOX, 22 (36%) had either a pathCR (n=13) or a CCR (n=9). Of the 49 patients who underwent TME, all had R0 resections and 23 (47%) had tumor response greater than 90%, including 13 (27%) who experienced a pathCR. Of the 28 patients who received all 8 cycles of FOLFOX, 8 experienced a pathCR (29%) and 3 a CCR (11%). No serious adverse events occurred that required a delay in treatment during FOLFOX or chemoradiation. FOLFOX and chemoradiation before planned TME results in tumor regression, a high rate of delivery of planned therapy, and a substantial rate of pathCRs, and offers a good platform for nonoperative management in select patients.

Neoadjuvant chemotherapy without routine use of radiation therapy for patients with locally advanced rectal cancer: a pilot trial

PURPOSE

Although neoadjuvant chemoradiotherapy achieves low local recurrence rates in clinical stages II to III rectal cancer, it delays administration of optimal chemotherapy. We evaluated preoperative infusional fluorouracil, leucovorin, and oxaliplatin (FOLFOX)/bevacizumab with selective rather than consistent use of chemoradiotherapy.

PATIENTS AND METHODS

Thirty-two patients with clinical stages II to III rectal cancer participated in this single-center phase II trial. All were candidates for low anterior resection with total mesorectal excision (TME). Patients were to receive six cycles of FOLFOX, with bevacizumab included for cycles 1 to 4. Patients with stable/progressive disease were to have radiation before TME, whereas responders were to have immediate TME. Postoperative radiation was planned if R0 resection was not achieved. Postoperative FOLFOX × 6 was recommended, but adjuvant regimens were left to clinician discretion. The primary outcome was R0 resection rate.

RESULTS

Between April 2007 and December 2008, 32 (100%) of 32 study participants had R0 resections. Two did not complete preoperative chemotherapy secondary to cardiovascular toxicity. Both had preoperative chemoradiotherapy and then R0 resections. Of 30 patients completing preoperative chemotherapy, all had tumor regression and TME without preoperative chemoradiotherapy. The pathologic complete response rate to chemotherapy alone was 8 of 32 (25%; 95% CI, 11% to 43%). The 4-year local recurrence rate was 0% (95% CI, 0% to 11%); the 4-year disease-free survival was 84% (95% CI, 67% to 94%).

CONCLUSION

For selected patients with clinical stages II to III rectal cancer, neoadjuvant chemotherapy and selective radiation does not seem to compromise outcomes. Preoperative Radiation or Selective Preoperative Radiation and Evaluation Before Chemotherapy and TME (PROSPECT), a randomized phase III trial to validate this experience, is now open in the US cooperative group network.

A phase II study of cixutumumab (IMC-A12, NSC742460) in advanced hepatocellular carcinoma

BACKGROUND & AIMS

IGF-IR is implicated in hepatic carcinogenesis. This and preliminary evidence of biological activity of anti-IGF-1R monoclonal antibody cixutumumab in phase I trials prompted this phase II study.

METHODS

Patients with advanced HCC, Child-Pugh A-B8, received cixutumumab 6mg/kg weekly, in a Simon two-stage design study, with the primary endpoints being 4-month PFS and RECIST-defined response rate. Tissue and circulating markers plus different HCC scoring systems were evaluated for correlation with PFS and OS.

RESULTS

As a result of pre-specified futility criteria, only stage 1 was accrued: N=24: median age 67.5 years (range 49-83), KPS 80% (70-90%), 20 males (83%), 9 stage III (37%)/15 stage IV (63%), 18 Child-Pugh A (75%), 11 HBV (46%)/10 HCV (42%)/11 alcoholic cirrhosis (46%)/2 NASH (8%), 11 (46%) diabetic. Median number of doses: 7 (range 1-140). Grade 3/4 toxicities >10% included: diabetes, elevated liver function tests, hyponatremia, and lymphopenia. Four-month PFS was 30% (95% CI 13-48), and there were no objective responses. Median overall survival was 8 months (95% CI 5.8-14). IGF-R1 staining did not correlate with outcome. Elevated IGFBP-1 correlated with improved PFS (1.2 [95% CI 1-1.4]; p 0.009) and OS (1.2 [95% CI 1.1-1.4]; p 0.003).

CONCLUSIONS

Cixutumumab monotherapy did not have clinically meaningful activity in this unselected HCC population. Grade 3-4 hyperglycemia occurred in 46% of patients. Elevated IGFBP-1 correlated with improved PFS and OS.

Systemic therapy for advanced pancreatic neuroendocrine tumors: an update

Well-differentiated neuroendocrine tumors (NETs) can be subdivided into carcinoid and pancreatic NETs (pancNETs). Although these tumors share many morphologic and clinical characteristics, carcinoid tumors appear to be far less sensitive to therapeutic agents than pancNETs, and recent advances approved for pancNETs have not been submitted for FDA approval in patients with carcinoid tumors. Treatment options for patients with advanced pancNETs are multidisciplinary and include surgical resection, liver-directed therapies, and systemic therapies. Cytotoxic therapies, such as temozolomide, fluorouracil, oxaliplatin, and streptozocin-based chemotherapy regimens, are active against some pancNETs, and can play a role in the palliation of patients with advanced disease and symptoms related to tumor bulk. Two therapies were recently approved for progressive well-differentiated pancNETs: sunitinib and everolimus. Both agents showed improved progression-free survival in patients with progressive pancNETs, but can also result in nontrivial toxicities, and therefore should only be considered in patients with progressing and advanced or symptomatic disease. This article discusses these recent trials and provides an update of systemic treatment options in patients with well-differentiated pancNETs.