Synergistic combination of cytotoxic chemotherapy and cyclin-dependent kinase 4/6 inhibitors in biliary tract cancers.

BACKGROUND AND AIMS: Biliary tract cancers (BTCs) are uncommon, but highly lethal, gastrointestinal malignancies. Gemcitabine/cisplatin is a standard-of-care systemic therapy, but has a modest impact on survival and harbors toxicities, including myelosuppression, nephropathy, neuropathy, and ototoxicity. Whereas BTCs are characterized by aberrations activating the cyclinD1/cyclin-dependent kinase (CDK)4/6/CDK inhibitor 2a/retinoblastoma pathway, clinical use of CDK4/6 inhibitors as monotherapy is limited by lack of validated biomarkers, diffident preclinical efficacy, and development of acquired drug resistance. Emerging studies have explored therapeutic strategies to enhance the antitumor efficacy of CDK4/6 inhibitors by the combination with chemotherapy regimens, but their mechanism of action remains elusive. APPROACH AND RESULTS: Here, we report in vitro and in vivo synergy in BTC models, showing enhanced efficacy, reduced toxicity, and better survival with a combination comprising gemcitabine/cisplatin and CDK4/6 inhibitors. Furthermore, we demonstrated that abemaciclib monotherapy had only modest efficacy attributable to autophagy-induced resistance. Notably, triplet therapy was able to potentiate efficacy through elimination of the autophagic flux. Correspondingly, abemaciclib potentiated ribonucleotide reductase catalytic subunit M1 reduction, resulting in sensitization to gemcitabine. CONCLUSIONS: As such, these data provide robust preclinical mechanistic evidence of synergy between gemcitabine/cisplatin and CDK4/6 inhibitors and delineate a path forward for translation of these findings to preliminary clinical studies in advanced BTC patients.

Changes in Prescribing Patterns in Stage III Colon Cancer.

BACKGROUND: For patients with resected stage III colon cancer, 6 months of adjuvant fluoropyrimidine-based chemotherapy has been the standard of care. The IDEA collaboration aimed to evaluate whether 3 months of adjuvant chemotherapy was noninferior to 6 months. Despite failing to meet its primary endpoint, the subgroup analyses demonstrated noninferiority based on regimen and treatment duration when a risk-stratified approach was used. PATIENTS AND METHODS: To evaluate the impact of the results of the IDEA collaboration, we evaluated adjuvant chemotherapy prescribing practice patterns, including planned adjuvant treatment regimen and duration from January 1, 2016, to January 31, 2021. The time period was selected to evaluate chemotherapy prescribing patterns prior to the abstract presentation of the IDEA collaboration in June 2017 and after full manuscript publication in March 2018. RESULTS: A total of 399 patients with stage III colon cancer who received adjuvant chemotherapy were included in the analysis. A significant increasing trend for use of 3 months of adjuvant chemotherapy was observed after presentation of the IDEA abstract (P<.001). A significant change in CAPOX (capecitabine/oxaliplatin) prescribing was also observed, increasing from 14% of patients prior to presentation of the IDEA abstract to 48% after presentation (P<.001). Comparing 3 months of CAPOX with 6 months of FOLFOX (fluorouracil/leucovorin/oxaliplatin), 3 months of CAPOX use also steadily increased over time (adjusted odds ratio [aOR], 1.28; 95% CI, 1.20-1.37; P<.001). Among subgroups of interest, no differences in adoption of CAPOX were observed. The adoption of 3 months of CAPOX was similar in patients with low-risk cancer (aOR, 1.27; 95% CI, 1.17-1.37) and those with high-risk cancer (aOR, 1.31; 95% CI, 1.16-1.47). CONCLUSIONS: Despite the IDEA collaboration failing to demonstrate noninferiority of 3 months' duration of adjuvant therapy compared with 6 months, the findings have influenced practice prescribing patterns, favoring CAPOX and a shorter duration of planned adjuvant treatment.

Managing Metastatic Extrapulmonary Neuroendocrine Carcinoma After First-Line Treatment.

PURPOSE OF REVIEW: Extrapulmonary neuroendocrine carcinoma (EP-NEC) is a rare, aggressive malignancy that can arise from any organ and frequently presents with distant metastases. Advanced disease has a poor prognosis with median overall survival (OS) rarely exceeding 1 year even with systemic therapy. The management paradigm of advanced/metastatic EP-NEC has been extrapolated from small cell lung cancer (SCLC) and commonly consists of 1st line therapy with etoposide and platinum (cisplatin or carboplatin), followed by alternative cytotoxic regimens at the time of progression. Only a minority of patients are able to receive 2nd line therapy, and cytotoxics derived from the SCLC paradigm such as topotecan or lurbinectedin have very limited activity. We aimed to evaluate emerging therapeutic options in the 2nd and later lines and survey potential future developments in this space. RECENT FINDINGS: After a long period of stagnation in treatment options and outcomes, more promising regimens are gradually being utilized in the 2nd line setting including systemic therapy combinations such as FOLFIRI, FOLFOX, modified FOLFIRINOX, CAPTEM, and, more recently, novel checkpoint inhibitors such as nivolumab and ipilimumab. Simultaneously, advances in the understanding of disease biology are helping to refine patient selection and identify commonalities between NEC and their sites of origin which may eventually lead to additional targeted therapy options. While many questions remain, contemporary developments give grounds for optimism that improved outcomes for EP-NEC will soon be within reach.

Treatment landscape of advanced high-grade neuroendocrine neoplasms.

Grade 3 neuroendocrine neoplasms (NEN G3) are high-grade (Ki-67 index >20%) neuroendocrine malignancies that comprise both rapidly proliferating, well-differentiated neuroendocrine tumors (NET G3) and poorly differentiated neuroendocrine carcinomas (NEC). The phenotypic differences between NET G3 and NEC stem from differences in their underlying genomic alterations. As a result of these differences, NET G3 is molecularly, radiologically, and prognostically distinct from NEC. The optimal management of NET G3 and NEC is currently being refined through clinical trials that focus on NET G3 and NEC as separate entities. This review aims to summarize the current understanding of NEN G3 by distinguishing between NET G3 and NEC and describing the clinical implications associated with each.

Survival and Incidence Patterns of Pancreatic Neuroendocrine Tumors Over the Last 2 Decades: A SEER Database Analysis.

BACKGROUND: Pancreatic neuroendocrine tumors (pNETs) are rare cancers with outcomes determined by multiple factors including grade, stage, and clinical presentation. In this study, we aimed to determine the prognosis of patients with pNETs using a large population-based database. MATERIALS AND METHODS: In this population-based study, we identified patients with pNETs from the SEER 18 registry (2000-2016) using a combination of ICD-O-3 and histology codes. We calculated age-adjusted incidence rates using SEER*Stat 8.3.5. In addition, we analyzed overall survival (OS) using the Kaplan-Meier method, and investigated prognostic factors using a multivariable Cox proportional hazards model. RESULTS: A total of 8944 pNETs patients were identified. Annual incidence rates increased from 0.27 to 1.00 per 100 000. This was largely explained by an increase in number of patients diagnosed with localized disease in more recent years (2012-2016). Median OS was 68 months (95% CI [64, 73]) and 5-year OS rates in localized, regional, and metastatic disease were 83%, 67%, and 28%, respectively. There was a significant improvement in OS for patients diagnosed between 2009 and 2016 (median OS 85 months) compared with those diagnosed between 2000 and 2008 (median OS 46 months) (HR 0.66; 95% CI [0.62, 0.70]). This improvement in OS was consistent across all stages. CONCLUSIONS AND RELEVANCE: This study shows a steady increase pNETs incidence with notable stage migration to earlier stages in recent years. This increase in incidence is accompanied by a significant improvement in survival across different disease stages.

The Role of Systemic Therapy in Resectable Colorectal Liver Metastases: Systematic Review and Network Meta-Analysis.

BACKGROUND: Despite multiple randomized trials, the role of perioperative chemotherapy in colorectal cancer liver metastasis (CRLM) is still under debate. In this systematic review and network meta-analysis (NMA), we aim to evaluate the efficacy of perioperative systemic therapies for patients with CRLM. METHODS: We searched various databases for abstracts and full-text articles published from database inception through May 2021.We included randomized controlled trials (RCTs) comparing the addition of perioperative (post, pre, or both) systemic therapies to surgery alone in patients with CRLM. The outcomes were compared according to the chemotherapy regimen using a random effects model. Outcomes of interest included disease-free survival (DFS) and overall survival (OS). RESULTS: Seven RCTs with a total of 1504 patients with CRLM were included. Six studies included post-operative treatment and one evaluated perioperative (pre- and postoperative) therapy. Fluoropyrimidine-based chemotherapy was the most used systemic therapy. NMA showed benefit of adding perioperative therapy to surgery in terms of DFS (HR 0.73, 95% CI 0.63 to 0.84). However, these findings did not translate into a statistically significant OS benefit (HR 0.88, 95% CI 0.74 to 1.05). NMA did not show any advantage of one regimen over another including oxaliplatin or irinotecan. CONCLUSIONS: This systematic review and NMA of 7 RCTs found that the addition of perioperative systemic treatment for resectable CRLM could improve disease-free survival but not overall survival. Based on the findings, addition of perioperative treatment in resectable CRLM should be individualized weighing the risks and benefits.

Germline Cancer Susceptibility Gene Testing in Unselected Patients With Colorectal Adenocarcinoma: A Multicenter Prospective Study.

BACKGROUND & AIMS: Hereditary factors play a role in the development of colorectal cancer (CRC). Identification of germline predisposition can have implications on treatment and cancer prevention. This study aimed to determine the prevalence of pathogenic germline variants (PGVs) in CRC patients using a universal testing approach, association with clinical outcomes, and the uptake of family variant testing. METHODS: We performed a prospective multisite study of germline sequencing using a more than 80-gene next-generation sequencing platform among CRC patients (not selected for age or family history) receiving care at Mayo Clinic Cancer Centers between April 1, 2018, and March 31, 2020. RESULTS: Of 361 patients, the median age was 57 years (SD, 12.4 y), 43.5% were female, 82% were white, and 38.2% had stage IV disease. PGVs were found in 15.5% (n = 56) of patients, including 44 in moderate- and high-penetrance cancer susceptibility genes. Thirty-four (9.4%) patients had incremental clinically actionable findings that would not have been detected by practice guideline criteria or a CRC-specific gene panel. Only younger age at diagnosis was associated with the presence of PGVs (odds ratio, 1.99; 95% CI, 1.12-3.56). After a median follow-up period of 20.7 months, no differences in overall survival were seen between those with or without a PGV (P = .2). Eleven percent of patients had modifications in their treatment based on genetic findings. Family cascade testing was low (16%). CONCLUSIONS: Universal multigene panel testing in CRC was associated with a modest, but significant, detection of heritable mutations over guideline-based testing. One in 10 patients had changes in their management based on test results. Uptake of cascade family testing was low, which is a concerning observation that warrants further study.

A pilot study of Pan-FGFR inhibitor ponatinib in patients with FGFR-altered advanced cholangiocarcinoma.

Background Biliary tract cancers (BTC) are rare, chemo resistant and are associated with a poor prognosis. Preclinical and early clinical work had demonstrated interesting anti-tumor activity from targeting fibroblast growth factor receptor (FGFR) pathway. We hypothesized that ponatinib, a multi-targeted tyrosine kinase inhibitor with activity against FGFR, would be active in BTC patients with FGFR alterations. Methods This was a multi-center, single institution pilot study of ponatinib in patients with advanced, refractory BTC with FGFR alterations. The primary end point was overall response rate, with secondary points of overall survival (OS), progression-free survival (PFS) and Health Related Quality of Life (HRQoL) assessment. Results Twelve patients were enrolled prior to early termination of the trial. Partial responses were observed in 1 from 12 patients. Median PFS was 2.4 months and median OS was 15.7 months. All observed toxicities were manageable and reversible. Toxicities were mild, with lymphopenia (75%), rash (63%) and fatigue (50%) being the most frequent. No significant detriment in global QoL was observed. Conclusions Ponatinib as a single agent in FGFR altered BTC is tolerable with limited clinical activity. This is the first report of prospective assessment of FGFR inhibition in BTC using ponatinib, and the first study to report its effect on HRQoL. Further development of ponatinib will involve correlative studies to better refine patient selection, focus on combinations with other molecular targeted agents, conventional cytotoxic chemotherapy, and studies to better understand mechanisms of treatment resistance.

Bile Acid Malabsorption in Patients with Neuroendocrine Tumors.

BACKGROUND: Chronic diarrhea in patients with neuroendocrine tumors (NET) may be caused by bioactive products of NET, bile acid malabsorption (BAM), ileal resection (IR) or steatorrhea. AIM: To quantitate BA and fat malabsorption in NET with diarrhea. METHODS: Part of evaluation in medical oncology clinical practice, 67 patients [42F, 25 M; median age 64.0 y (17.0 IQR)] with well-differentiated NET and diarrhea underwent clinically indicated measurements of 48-h fecal BA [(FBA), fecal weight (normal < 400 g/48 h), fecal fat (normal < 7 g/day) in n = 52] and fasting serum 7αC4 (marker of hepatic BA synthesis, n = 30) between 01/2018 and 11/2020. IR had been performed in 45 patients. BAM diagnosis was based on FBA criteria: elevated total FBA (> 2337 µmol/48 h) or > 10% primary FBA or combination > 4% primary FBA plus > 1000 µmol total FBA/48 h. We also measured fecal elastase (for pancreatic insufficiency) in 13 patients. RESULTS: BAM was present in 48/52 (92%) patients with NET. There were significant correlations between total FBA and 48-h fecal weight (Rs = 0.645, P < 0.001). Mean length of IR was 47 cm; in patients with IR < 25 cm, total FBA was elevated in 85% and primary FBA > 10% in 69%. In 22 patients with no IR, 13/15 tested (87%) had BAM. Among 6 patients with pancreatic NET and no IR, 80% had BAM. Fecal fat was ≥ 15 g/day in 18/42 (43%). In 4/17 (24%) with IR < 25 cm and 8/19 (42%) patients with IR > 25 cm fecal fat was 44.0 (40.5) and 38.0 (38.0)g/day, respectively. CONCLUSION: A majority of patients with NET and diarrhea had BAM, even with < 25 cm or no IR.

The treatment landscape for gastroesophageal adenocarcinomas.

The treatment landscape for gastroesophageal adenocarcinomas has significantly changed over the last year. The addition of nivolumab to first-line chemotherapy has led to survival benefit in patients who have metastatic gastroesophageal adenocarcinoma with a programmed death ligand 1 combined positive score of 5 or greater. Similarly, in patients with metastatic human epidermal growth factor receptor 2 (HER2)-positive gastroesophageal adenocarcinoma, the addition of pembrolizumab to chemotherapy and trastuzumab has significantly improved efficacy. Furthermore, a phase 2 study revealed that trastuzumab deruxtecan, a new antibody-drug conjugate, significantly improved survival in comparison with chemotherapy among patients with HER2-positive gastric cancer in the refractory setting, and it produced a signal of efficacy in the second-line setting. Chemoimmunotherapy combinations are now considered the standard of care for a significant number of patients with gastroesophageal adenocarcinomas.

Outcomes on anti-VEGFR-2/paclitaxel treatment after progression on immune checkpoint inhibition in patients with metastatic gastroesophageal adenocarcinoma.

Through our involvement in KEYNOTE-059, we unexpectedly observed durable responses in two patients with metastatic gastroesophageal adenocarcinoma (mGEA) who received ramucirumab (anti-VEGFR-2)/paclitaxel after immune checkpoint inhibition (ICI). To assess the reproducibility of this observation, we piloted an approach to administer ramucirumab/paclitaxel after ICI in more patients, and explored changes in the immune microenvironment. Nineteen consecutive patients with mGEA received ICI followed by ramucirumab/paclitaxel. Most (95%) did not respond to ICI, yet after irRECIST-defined progression on ICI, all patients experienced tumor size reduction on ramucirumab/paclitaxel. The objective response rate (ORR) and progression-free survival (PFS) on ramucirumab/paclitaxel after ICI were higher than on the last chemotherapy before ICI in the same group of patients (ORR, 58.8% vs 11.8%; PFS 12.2 vs 3.0 months; respectively). Paired tumor biopsies examined by imaging mass cytometry showed a median 5.5-fold (range 4-121) lower frequency of immunosuppressive forkhead box P3+ regulatory T cells with relatively preserved CD8+ T cells, post-treatment versus pre-treatment (n = 5 pairs). We then compared the outcomes of these 19 patients with a separate group who received ramucirumab/paclitaxel without preceding ICI (n = 68). Median overall survival on ramucirumab/paclitaxel was longer with (vs without) immediately preceding ICI (14.8 vs 7.4 months) including after multivariate analysis, as was PFS. In our small clinical series, outcomes appeared improved on anti-VEGFR-2/paclitaxel treatment when preceded by ICI, in association with alterations in the immune microenvironment. However, further investigation is needed to determine the generalizability of these data. Prospective clinical trials to evaluate sequential treatment with ICI followed by anti-VEGF(R)/taxane are underway.

Treatment Outcomes of Well-Differentiated High-Grade Neuroendocrine Tumors.

INTRODUCTION: Recent classification of neuroendocrine neoplasms has defined well-differentiated high-grade neuroendocrine tumors (NET G3) as a distinct entity from poorly differentiated neuroendocrine carcinoma. The optimal treatment for NET G3 has not been well-described. This study aimed to evaluate metastatic NET G3 response to different treatment regimens. MATERIALS AND METHODS: This was a retrospective study of patients with NET G3 within the Mayo Clinic database. Patients' demographics along with treatment characteristics, responses, and survival were assessed. Primary endpoints were progression-free survival (PFS) and overall survival. Secondary endpoints were objective response rate (ORR) and disease control rate (DCR). RESULTS: Treatment data was available in 30 patients with median age of 59.5 years at diagnosis. The primary tumor was mostly pancreatic (73.3%). Ki-67 index was ≥55% in 26.7% of cases. Treatments included capecitabine + temozolomide (CAPTEM) (n = 20), lutetium 177 DOTATATE (PRRT; n = 10), Platinum-etoposide (EP; n = 8), FOLFOX (n = 7), and everolimus (n = 2). CAPTEM exhibited ORR 35%, DCR 65%, and median PFS 9.4 months (95% confidence interval, 2.96-16.07). Both EP and FOLFOX showed similar radiographic response rates with ORR 25.0% and 28.6%; however, median PFS durations were quite distinct at 2.94 and 13.04 months, respectively. PRRT had ORR of 20%, DCR of 70%, and median PFS of 9.13 months. CONCLUSION: Among patients with NET G3, CAPTEM was the most commonly used treatment with clinically meaningful efficacy and disease control. FOLFOX or PRRT are other potentially active treatment options. EP has some activity in NET G3, but responses appear to be short-lived. Prospective studies evaluating different treatments effects in patients with NET G3 are needed to determine an optimal treatment strategy. IMPLICATIONS FOR PRACTICE: High-grade well-differentiated neuroendocrine tumors (NET G3) are considered a different entity from low-grade NET and neuroendocrine carcinoma in terms of prognosis and management. The oral combination of capecitabine and temozolomide is considered a good option in the management of metastatic NET G3 and may be preferred. FOLFOX is another systemic option with reasonable efficacy. Similar to other well-differentiated neuroendocrine tumors, peptide receptor radionuclide therapy seems to have some efficacy in these tumors.

Causes of Death Following Nonmetastatic Colorectal Cancer Diagnosis in the U.S.: A Population-Based Analysis.

INTRODUCTION: Because of the improved colorectal cancer (CRC) survival in the U.S., patients may live long enough after CRC diagnosis to the point where non-cancer-related comorbidities may considerably impact their overall survival. In this study, we perform a long-term analysis of causes of death (CODs) following nonmetastatic CRC with respect to different demographic and tumor-related criteria. MATERIALS AND METHODS: We gained access to the Surveillance, Epidemiology, and End Results data to review patients diagnosed with nonmetastatic CRC during 2000-2015. We calculated standardized mortality ratios (SMRs) for each COD following CRC. SMRs represented the change of risk of a specific COD following CRC diagnoses when compared with the risk in the general U.S. RESULTS: We reviewed 302,345 patients, of whom 112,008 died during the study period. More deaths (68.3%) occurred within 5 years following nonmetastatic CRC diagnosis, with 76,486 deaths. CRC was the most common COD (51.4%) within 5 years of diagnosis followed by heart disease (15.2%) and other cancers (8.4%). As time passed after diagnosis, the number of CRC deaths decreased, and other noncancer causes increased to the point that after 10 years only 10.4% of deaths were attributed to CRC, 15.3% were attributed to other cancers, and 34.2% were secondary to heart disease. CONCLUSION: Following nonmetastatic CRC diagnosis, most deaths remain secondary to CRC. Other causes, including other cancers and cardiovascular disease, represent a significant number of deaths, especially in the 5 years following initial CRC diagnosis. Our findings help guide counseling patients with CRC regarding future health risks. IMPLICATIONS FOR PRACTICE: Most common causes of death following nonmetastatic colorectal cancer (CRC) are heart diseases, other cancers, chronic obstructive pulmonary disease, and cerebrovascular diseases. Physicians should counsel patients regarding survivorship with cancer screening and focus on prevention of noncancer deaths. These findings should be considered by physicians who give care for survivors of nonmetastatic CRC.

Circulating Tumor DNA-Based Testing and Actionable Findings in Patients with Advanced and Metastatic Pancreatic Adenocarcinoma.

PURPOSE: Recent advances in molecular diagnostic technologies allow for the evaluation of solid tumor malignancies through noninvasive blood sampling, including circulating tumor DNA profiling (ctDNA). Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis, often because of late presentation of disease. Diagnosis is often made using endoscopic ultrasound or endoscopic retrograde cholangiopancreatography, which often does not yield enough tissue for next-generation sequencing. With this study, we sought to characterize the ctDNA genomic alteration landscape in patients with advanced PDAC with a focus on actionable findings. MATERIALS AND METHODS: From December 2014 through October 2019, 357 samples collected from 282 patients with PDAC at Mayo Clinic underwent ctDNA testing using a clinically available assay. The majority of samples were tested using the 73-gene panel which includes somatic genomic targets, including complete or critical exon coverage in 30 and 40 genes, respectively, and in some, amplifications, fusions, and indels. Clinical data and outcome variables were available for 165 patients; with 104 patients at initial presentation. RESULTS: All patients included in this study had locally advanced or metastatic PDAC. Samples having at least one alteration, when variants of unknown significance (VUS) were excluded, numbered 266 (75%). After excluding VUS, therapeutically relevant alterations were observed in 170 (48%) of the total 357 cohort, including KRAS (G12C), EGFR, ATM, MYC, BRCA, PIK3CA, and BRAF mutations. KRAS, SMAD, CCND2, or TP53 alterations were seen in higher frequency in patients with advanced disease. CONCLUSION: Our study is the largest cohort to date that demonstrates the feasibility of ctDNA testing in PDAC. We provide a benchmark landscape upon which the field can continue to grow. Future applications may include use of ctDNA to guide treatment and serial monitoring of ctDNA during disease course to identify novel therapeutic targets for improved prognosis. IMPLICATIONS FOR PRACTICE: Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis often due to late presentation of disease. Biopsy tissue sampling is invasive and samples are often inadequate, requiring repeated invasive procedures and delays in treatment. Noninvasive methods to identify PDAC early in its course may improve prognosis in PDAC. Using ctDNA, targetable genes can be identified and used for treatment.

Mismatch Repair (MMR) Gene Alteration and BRAF V600E Mutation Are Potential Predictive Biomarkers of Immune Checkpoint Inhibitors in MMR-Deficient Colorectal Cancer.

BACKGROUND: Immune checkpoint inhibitor (ICI) therapy is highly effective in metastatic mismatch repair-deficient (MMR-D) colorectal cancer (CRC). In this study, we evaluated molecular and clinical predictors of ICI response in MMR-D CRC. MATERIALS AND METHODS: Patient databases at four cancer institutions were queried. The Fisher exact test was performed to test the association of clinical and molecular markers. The Kaplan-Meier method was used to estimate progression-free survival (PFS) and compared by the log-rank test. Twelve- and 24-month PFS rates were compared by the Z test. RESULTS: A total of 60 patients with CRC with MMR-D/microsatellite instability-high who previously received ICIs were identified. Patients with liver metastasis had a lower overall response rate as compared with other sites of metastasis (36.4% vs. 68.7%; p = .081). Patients with MLH1/PMS2 loss had worse 1-year and 2-year PFS rates compared with patients with MSH2/MSH6 loss (84.2% vs. 57.8% and 78.2% vs. 54.2%, respectively; p < .001). There were improved 1-year and 2-year PFS rates in patients with wild-type BRAF when compared with patients with BRAF V600E mutation (73.3% vs. 40%, and 73.3% vs. 26.7%; respectively; p < .001). Patients aged >65 had significantly worse PFS rates as compared with patients aged ≤65 (p < .001). CONCLUSION: BRAF V600E mutation, MLH1 and/or PMS2 loss, as well as age >65 years and liver metastasis, may be predictive of duration of ICI response in patients with MMR-D CRC. Larger cohorts are needed to confirm our findings. IMPLICATIONS FOR PRACTICE: The results of this study reveal clinically important biomarkers that potentially predict immune checkpoint inhibitor response in patients with mismatch repair-deficient colorectal cancer.

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia: DIPNECH.

PURPOSE OF REVIEW: Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a rare premalignant condition. Over the past decade, there has been increased recognition and reporting of DIPNECH in the literature. Currently, our understanding is that DIPNECH has a predilection to nonsmoking females around their sixth decade of life. The patients usually present with chronic cough, dyspnea, and computed tomography (CT) showing multifocal pulmonary nodules with associated mosaic attenuation. The clinic history is largely driven by constrictive obliterative bronchiolitis, which typically has an indolent course with progressive respiratory decline and difficult to treat symptoms. RECENT FINDINGS: DIPNECH has been found to be associated with carcinoid tumors. Recent data has found that symptomatic DIPNECH patients respond to somatostatin analog (SSA). SSAs provide improvement in symptoms and pulmonary function tests. According to small studies and case series SSAs can be used in conjunction with steroids and bronchodilators for the treatment of respiratory symptoms. SUMMARY: DINPNECH is a premalignant condition that can transform into carcinoid tumors. Although the recent data suggest the potential efficacy of SSA, further studies are needed to validate such results in prospective fashion in addition to investigating other therapeutic agents.

Multifocality is not associated with worse survival in sporadic pancreatic neuroendocrine tumors.

BACKGROUND AND OBJECTIVES: Pancreatic neuroendocrine tumors (pNETs) in patients with hereditary cancer syndromes are typically multifocal. In contrast, sporadic pNETs are usually unifocal and the incidence of multifocal sporadic pNETs is unknown. The primary aim of this study was to investigate the incidence of multifocality in sporadic pNETs and any associated effect on recurrence risk and survival. METHODS: Patients who underwent resection of pNETs at Mayo Clinic from 2000 to 2019 were identified and clinical data were obtained from medical records. Syndromic disease was defined as pNETs arising in the setting of a hereditary cancer syndrome. Statistical comparisons were made using χ2 , Fisher's exact, and Kruskal-Wallis tests and survival was assessed using the Kaplan-Meier method. RESULTS: Six hundred and sixty-one patients with sporadic pNETs and fifty-nine with syndromic pNETs were identified. Multifocal disease was present in 4.8% of sporadic patients and 84.7% of syndromic patients (p < .001). Within patients with sporadic pNETs, clinicopathologic features and recurrence-free and overall survival were similar between patients with unifocal and multifocal disease. CONCLUSIONS: Multifocal sporadic pNETs are rare and multifocality is not associated with worse survival or increased recurrence risk. Patients with multifocal sporadic pNETs can likely be safely managed with a combination of resection and observation as indicated for each tumor.

Management of well-differentiated neuroendocrine tumors.

Neuroendocrine tumors (NETs) are a heterogeneous group of epithelial neoplasms with predominantly neural and endocrine differentiation that have the ability to produce peptide hormones and other biologically active substances. The histologic characterization of NETs based on differentiation and grading is crucial to determining prognosis and treatment. Surgery still offers the best chance of cure for patients with NETs, and tumor resection is the preferred approach when possible. For locally advanced or metastatic disease, approaches to treatment can vary widely depending on the extent of disease and goals of therapy. A better understanding of the biology of NETs acquired over the last decade has facilitated the development of targeted therapies, such as everolimus and a variety of tyrosine kinase inhibitors. Furthermore, the field of theranostics has led to dramatic improvements in our diagnostic and treatment abilities. Chemotherapy has a role in the treatment of NETs, evidenced by the benefit shown with the combination of temozolomide and capecitabine to treat pancreatic NETs. Somatostatin analogues are a mainstay of treatment because they reduce secretory products and have antiproliferative effects on NET cells. In this work, we aim to review the landscape for the diagnosis and treatment of well-differentiated NETs.

Causes of death after breast cancer diagnosis: A US population-based analysis.

BACKGROUND: The focus on noncancer causes of death in patients with breast cancer (BC) remains superficial. The objective of the current study was to assess and quantify causes of death after BC diagnosis. METHODS: In total, 754,270 women with BC in the United States who were diagnosed during 2000 through 2015 and retrieved from the Surveillance, Epidemiology, and End Results (SEER) program were studied. Standardized mortality ratios (SMRs) for causes of death were calculated. RESULTS: Of the included patients, 183,002 (24.3%) died during the follow-up period. The greatest proportion of deaths (46.2%) occurred within 1 to 5 years after diagnosis. Most deaths occurred from BC itself or from other cancers, and the number of BC deaths decreased as more years passed after diagnosis. The most common noncancer causes of death within <10 years after diagnosis were heart diseases followed by cerebrovascular diseases. However, >10 years after diagnosis, the most common noncancer causes of death were heart diseases followed by Alzheimer disease. Patients had a statistically significant higher risk of death from chronic liver diseases within 5 to 10 years after diagnosis compared with the general population (SMR, 1.23; 95% CI, 1.09-1.38) and had statistically significant higher risks of death from Alzheimer disease (SMR, 1.21; 95% CI, 1.14-1.29) and from diseases of the heart (SMR, 1.06; 95% CI, 1.02-1.09) >10 years after diagnosis. CONCLUSIONS: Although BC remains the most common cause of death after BC diagnosis, other non-BC causes of death (mainly heart and cerebrovascular diseases) represent a significant number of deaths among patients with BC. These findings provide important insight into how BC survivors should be counselled regarding future health risks.

Homologous Recombination Repair Defect May Predict Treatment Response to Peptide Receptor Radionuclide Therapy for Neuroendocrine Tumors.

Lutetium-177-dotatate (177 Lu-dotatate), a form of peptide receptor radionuclide therapy, was approved by the U.S. Food and Drug Administration for the treatment of advanced somatostatin receptor-positive gastroenteropancreatic neuroendocrine tumors (NETs) in 2018 based on the promising results of the NETTER-1 trial for grade 1-2 midgut NETs. Here, we present a patient with a grade 3 pancreatic neuroendocrine tumor and BRCA1 germline mutation who had a significant response to 177 Lu-dotatate.