Entinostat in patients with relapsed or refractory abdominal neuroendocrine tumors.

BACKGROUND: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are rare neoplasms with an increasing annual incidence and prevalence. Many are metastatic at presentation or recur following surgical resection and require systemic therapy, for which somatostatin analogs such as octreotide or lanreotide comprise typical first-line therapies. Nonetheless, treatment options remain limited. Epigenetic processes such as histone modifications have been implicated in malignant transformation and progression. In this study, we evaluated the anti-proliferative effects of a histone deacetylase (HDAC) inhibitor, entinostat, which was computationally predicted to show anti-cancer activity, as confirmed in in vitro and in vivo models of GEP-NETs. METHODS: This was a phase II study to evaluate the efficacy and safety of entinostat in patients with relapsed or refractory abdominal NETs. The primary objective was to estimate the objective response rate to entinostat. Additionally, with each patient as his/her own control we estimated the rates of tumor growth prior to enrollment on study and while receiving entinostat. Patients received 5 mg entinostat weekly until disease progression or intolerable toxicity. The dose could be changed to 10 mg biweekly for patients who did not experience grade ≥ 2 treatment-related adverse events (AEs) in cycle 1, but was primarily administered at the starting 5 mg weekly dose. RESULTS: The study enrolled only 5 patients due to early termination by the drug sponsor. The first patient that enrolled had advanced disease and died within days of enrollment before follow-up imaging due to a grade 5 AE unrelated to study treatment and was considered non-evaluable. Best RECIST response for the remaining 4 patients was stable disease (SD) with time on study of 154+, 243, 574, and 741 days. With each patient as his/her own control, rates of tumor growth on entinostat were markedly reduced with rates 17%, 20%, 33%, and 68% of the rates prior to enrollment on study. Toxicities possibly or definitely related to entinostat included grade 2/3 neutrophil count decrease [2/4 (50%)/ 2/4 (50%)], grade 3 hypophosphatemia [1/4, (25%)], grade 1/2 fatigue [1/4 (25%)/ 2/4 (50%)], and other self-limiting grade 1/2 AEs. CONCLUSION: In the treatment of relapsed or refractory abdominal NETs, entinostat 5 mg weekly led to prolonged SD and reduced the rate of tumor growth by 32% to 83% with an acceptable safety profile (ClinicalTrials.gov Identifier: NCT03211988).

Tumor Growth Rate Informs Treatment Efficacy in Metastatic Pancreatic Adenocarcinoma: Application of a Growth and Regression Model to Pivotal Trial and Real-World Data.

BACKGROUND: Methods for screening agents earlier in development and strategies for conducting smaller randomized controlled trials (RCTs) are needed. METHODS: We retrospectively applied a tumor growth model to estimate the rates of growth of pancreatic cancer using radiographic tumor measurements or serum CA 19-9 values from 3033 patients with stages III-IV PDAC who were enrolled in 8 clinical trials or were included in 2 large real-world data sets. RESULTS: g correlated inversely with OS and was consistently lower in the experimental arms than in the control arms of RCTs. At the individual patient level, g was significantly faster for lesions metastatic to the liver relative to those localized to the pancreas. Regardless of regimen, g increased toward the end of therapy, often by over 3-fold. CONCLUSIONS: Growth rates of PDAC can be determined using radiographic tumor measurement and CA 19-9 values. g is inversely associated with OS and can differentiate therapies within the same trial and across trials. g can also be used to characterize changes in the behavior of an individual's PDAC, such as differences in the growth rate of lesions based on metastatic site, and the emergence of chemoresistance. We provide examples of how g can be used to benchmark phase II and III clinical data to a virtual reference arm to inform go/no go decisions and consider novel trial designs to optimize and accelerate drug development.

Ethnic diversity in treatment response for colorectal cancer: proof of concept for radiomics-driven enrichment trials.

BACKGROUND: Several barriers hamper recruitment of diverse patient populations in multicenter clinical trials which determine efficacy of new systemic cancer therapies. PURPOSE: We assessed if quantitative analysis of computed tomography (CT) scans of metastatic colorectal cancer (mCRC) patients using imaging features that predict overall survival (OS) can unravel the association between ethnicity and efficacy. METHODS: We retrospectively analyzed CT images from 1584 mCRC patients in two phase III trials evaluating FOLFOX ± panitumumab (n = 331, 350) and FOLFIRI ± aflibercept (n = 437, 466) collected from August 2006 to March 2013. Primary and secondary endpoints compared RECIST1.1 response at month-2 and delta tumor volume at month-2, respectively. An ancillary study compared imaging phenotype using a peer-reviewed radiomics-signature combining 3 imaging features to predict OS landmarked from month-2. Analysis was stratified by ethnicity. RESULTS: In total, 1584 patients were included (mean age, 60.25 ± 10.57 years; 969 men). Ethnicity was as follows: African (n = 50, 3.2%), Asian (n = 66, 4.2%), Caucasian (n = 1413, 89.2%), Latino (n = 27, 1.7%), Other (n = 28, 1.8%). Overall baseline tumor volume demonstrated Africans and Caucasians had more advanced disease (p < 0.001). Ethnicity was associated with treatment response. Response per RECIST1.1 at month-2 was distinct between ethnicities (p = 0.048) with higher response rate (55.6%) in Latinos. Overall delta tumor volume at month-2 demonstrated that Latino patients more likely experienced response to treatment (p = 0.021). Radiomics phenotype was also distinct in terms of tumor radiomics heterogeneity (p = 0.023). CONCLUSION: This study highlights how clinical trials that inadequately represent minority groups may impact associated translational work. In appropriately powered studies, radiomics features may allow us to unravel associations between ethnicity and treatment efficacy, better elucidate mechanisms of resistance, and promote diversity in trials through predictive enrichment. CLINICAL RELEVANCE STATEMENT: Radiomics could promote clinical trial diversity through predictive enrichment, hence benefit to historically underrepresented racial/ethnic groups that may respond variably to treatment due to socioeconomic factors and built environment, collectively referred to as social determinants of health. KEY POINTS: •Findings indicate ethnicity was associated with treatment response across all 3 endpoints. First, response per RECIST1.1 at month-2 was distinct between ethnicities (p = 0.048) with higher response rate (55.6%) in Latinos. •Second, the overall delta tumor volume at month-2 demonstrated that Latino patients were more likely to experience response to treatment (p = 0.021). Radiomics phenotype was also distinct in terms of tumor radiomics heterogeneity (p = 0.023).

Design of placebo-controlled randomized trials of anticancer agents: Ethical considerations based on a review of published trials.

BACKGROUND: Limited information exists about the design of placebo-controlled cancer trials. Through a systematic review of trials published in 2013, we describe placebo use in randomized trials testing anticancer agents and analyze strategies that increase exposure to the experimental regimen. METHODS: Trials were classified as add-on (placebo in combination with standard treatment) or placebo-only. Strategies to allow more than half of the participants to receive the experimental regimen were reviewed. The risk-benefit ratio of receiving the experimental agent was considered favorable if the difference in primary outcome was significant (p ≤ 0.05), neutral if there was no significant difference in the primary outcome and the experimental agent did not add substantial toxicity, and unfavorable otherwise. RESULTS: Eighty trials were included (32,694 participants). Most trials were add-on (69%). The risk-benefit outcome was favorable, neutral, and unfavorable to the experimental agent in 52%, 32%, and 16% of placebo-only trials and 25%, 53%, and 22%, respectively, of add-on trials. Four strategies increased exposure to the experimental regimen: one-way crossover (23%), uneven randomization (21%), three-arms (13%), and randomized discontinuation design (4%); these strategies were used more often in placebo-only trials. CONCLUSION: A minority of participants received placebo alone and strategies to increase experimental exposure were used commonly. Fewer than half of the studies had favorable outcomes, thus defending the use of placebo controls, when there is no established treatment. Strategies that increase patient exposure to experimental agents rather than placebo may expose them to non-beneficial, sometimes toxic, experimental agents.

Emerging Therapeutic Implications of STK11 Mutation: Case Series.

STK11 was first recognized as a tumor suppressor gene in the late 1990s based on linkage analysis of patients with Peutz-Jeghers syndrome. STK11 encodes LKB1, an intracellular serine-threonine kinase involved in cellular metabolism, cell polarization, regulation of apoptosis, and DNA damage response. Recurrent somatic loss-of-function mutations occur in multiple cancer types, most notably in 13% of lung adenocarcinomas. Recent reports indicate that KRAS-mutant non-small cell lung cancers harboring co-mutations in STK11 do not respond to PD-1 axis inhibitors. We present three patients with STK11-mutated tumors and discuss the proposed mechanisms by which germline and somatic alterations in STK11 promote carcinogenesis, potential approaches for therapeutic targeting, and the new data on resistance to immune checkpoint inhibitors. KEY POINTS: STK11 is a tumor suppressor gene, and loss-of-function mutations are oncogenic, due at least in part to loss of AMPK regulation of mTOR and HIF-1-α. Clinical trials are under way, offering hope to patients whose STK11-mutated tumors are refractory and/or have progressed on chemotherapeutic regimens. Whether gastrointestinal cancers with STK11 loss of function will show the same outcome and potential refractoriness to immune therapy that were reported for lung cancer is unknown. However, physicians managing such patients should consider the experience in lung cancer, particularly outside the context of a clinical trial. In the CheckMate-057 trial lung tumors harboring co-mutations in KRAS and STK11 had an inferior response to PD-1 axis inhibitors. Coupled with the observation that STK11-mutated tumors were found to have a cold immune microenvironment regardless of KRAS status, the conclusion could extend to KRAS wild-type tumors with STK11 mutation. Current data suggest that the use of PD-1 axis inhibitors may be ill advised in the presence of STK11 mutation.

Cisplatin versus cetuximab with definitive concurrent radiotherapy for head and neck squamous cell carcinoma: An analysis of Veterans Health Affairs data.

BACKGROUND: The addition of cisplatin or cetuximab to radiation therapy (RT) improves outcomes in comparison with RT alone in the nonoperative management of head and neck squamous cell carcinoma (HNSCC), but limited data exist for comparing these approaches. Using Veterans Health Affairs data, this study compared the outcomes of patients treated with RT plus cisplatin or cetuximab. METHODS: Patients with stage III to IVb HNSCC who had been treated nonsurgically with RT and cisplatin or cetuximab from 2000 to 2016 within the Veterans Health Affairs system were identified. Patients were analyzed by the drug used in the first treatment cycle (intent to treat). Overall survival (OS) was compared by treatment group with Cox regression models, and propensity score (PS) methods were used to account for a treatment allocation bias. The risk of toxicities was determined, with logistic regression models fit into propensity-matched cohorts. RESULTS: A total of 4520 patients were included in the analysis with a median follow-up of 3 years: 83% received cisplatin. Cisplatin patients were younger (P < .001) and had fewer comorbidities (P < .001). In an unmatched analysis, cetuximab was associated with inferior OS (P < .001). After PS matching, cetuximab treatment remained statistically significantly associated with inferior OS (1.7 vs 4.1 years; hazard ratio, 1.61; 95% confidence interval, 1.44-1.79; P < .001). These differences remained significant across all primary HNSCC subsites and in comparison with low- and high-dose cisplatin. CONCLUSIONS: Cetuximab with RT yields inferior OS in comparison with cisplatin for the nonoperative management of stage III to IVb HNSCC. According to this study, cisplatin may be the most appropriate partner for RT in this setting.

Phase I/II Trial of Vandetanib and Bortezomib in Adults with Locally Advanced or Metastatic Medullary Thyroid Cancer.

LESSONS LEARNED: Vandetanib at a dose of 300 mg orally every day plus bortezomib 1.3 mg/m2 intravenously on days 1, 4, 8, and 11 could be administered safely.Assessing outcomes in 17 patients with medullary thyroid cancer, investigators considered the combination to be more difficult to administer than single-agent vandetanib and that achieving better outcomes was unlikely. Consequently, a planned phase II study was terminated early. BACKGROUND: The proto-oncogene RET (REarranged during Transfection) has a critical role in the pathogenesis of medullary thyroid cancer (MTC). Vandetanib (V), a multitargeted tyrosine kinase inhibitor approved for the treatment of MTC, is thought to inhibit RET in MTC. Supported by preclinical studies demonstrating that bortezomib (B) administration lowered RET mRNA and protein levels, we conducted a phase I study in advanced solid tumors of vandetanib in combination with bortezomib. The goal was to establish an RP2D (recommended phase II dose) for the combination of vandetanib plus bortezomib, a regimen envisioned as a dual strategy for targeting RET in MTC. METHODS: Patients with advanced solid tumors were treated with escalating doses of bortezomib or vandetanib to assess the safety and tolerability of daily oral vandetanib and intravenous (IV) bortezomib administered on days 1, 4, 8, and 11 of a 28-day cycle. Intrapatient dose escalation was allowed. RESULTS: Twenty-two patients were enrolled and received escalating mg/m2 bortezomib and mg vandetanib (number of patients) at initial doses of 1 and 100 (3), 1.3 and 100 (6), 1.3 and 200 (6), and 1.3 and 300 (7), respectively. Patients received a median of four cycles of bortezomib/vandetanib (range: 1-10), with 13 patients escalating to 1.3/200 and 10 to 1.3/300. G3 toxicities occurring in more than one patient included hypertension (24%), fatigue (19%), thrombocytopenia (10%), diarrhea (10%), and arthralgia (10%). There were no drug-related G4/5 toxicities. There was one dose-limiting toxicity, G3 thrombocytopenia, at bortezomib/vandetanib doses of 1.3/200 in cycle 2 that resolved without intervention. Four patients with a diagnosis of MTC (27%) had a partial response (PR). CONCLUSION: The MTD of the combination was established as bortezomib, 1.3 mg/m2 IV days 1, 4, 8, and 11 with vandetanib 300 mg p.o. daily. RECIST responses were observed in patients with a diagnosis of MTC.

Continued Tumor Reduction of Metastatic Pheochromocytoma/Paraganglioma Harboring Succinate Dehydrogenase Subunit B Mutations with Cyclical Chemotherapy.

Patients harboring germline mutations in the succinate dehydrogenase complex subunit B (SDHB) gene present with pheochromocytomas and paragangliomas (PPGL) that are more likely malignant and clinically aggressive. The combination chemotherapy cyclophosphamide, vincristine, and dacarbazine (CVD) was retrospectively evaluated in patients with SDHB-associated metastatic PPGL.Query Twelve metastatic PPGL patients harboring SDHB mutations/polymorphisms with undetectable SDHB immunostaining were treated with CVD. CVD therapy consisted of 750 mg/m2 cyclophosphamide with 1.4 mg/m2 vincristine on day 1 and 600 mg/m2 dacarbazine on days 1 and 2, every 21-28 days. Treatment outcome was determined by RECIST criteria as well as determination of response duration and progression-free and overall survivals. A median of 20.5 cycles (range 4-41) was administered. All patients had tumor reduction (12-100% by RECIST). Complete response was seen in two patients, while partial response was observed in 8. The median number of cycles to response was 5.5. Median duration of response was 478 days, with progression-free and overall survivals of 930 and 1190 days, respectively. Serial [18F]-fluorodeoxyglucose positron emission tomography and computed tomography imaging demonstrated continued incremental reduction in maximal standardized uptake values (SUVmax) values in 26/30 lesions. During treatment administration, the median SUV decreased from > 25 to < 6, indicating the efficacy of chemotherapy over a prolonged period of time. Prolonged therapy results in continued incremental tumor reduction, and is consistent with persistent drug sensitivity. CVD chemotherapy is recommended to be considered part of the initial management in patients with metastatic SDHB-related PPGL.

Phase I trial of belinostat with cisplatin and etoposide in advanced solid tumors, with a focus on neuroendocrine and small cell cancers of the lung.

The standard-of-care for advanced small cell lung cancer (SCLC) is chemotherapy with cisplatin+etoposide (C+E). Most patients have chemosensitive disease at the outset, but disease frequently relapses and limits survival. Efforts to improve therapeutic outcomes in SCLC and other neuroendocrine cancers have focused on epigenetic agents, including the histone deacetylase inhibitor belinostat. The primary objective was to determine the maximum tolerated dose of the combination of belinostat (B) with C+E. Belinostat was administered as a 48-h continuous intravenous infusion on days 1-2; cisplatin was administered as a 1-h intravenous infusion on day 2; and etoposide was administered as a 1-h intravenous infusion on days 2, 3, and 4. Twenty-eight patients were recruited in this single-center study. The maximum tolerated dose was belinostat 500 mg/m/24 h, cisplatin 60 mg/m, and etoposide 80 mg/m. The combination was safe, although some patients were more susceptible to adverse events. Hematologic toxicities were most commonly observed. Objective responses were observed in 11 (39%) of 28 patients and seven (47%) of 15 patients with neuroendocrine tumors (including SCLC). Patients carrying more than three copies of variant UGT1A1 (*28 and *60) had higher serum levels of belinostat because of slower clearance. DNA damage peaked at 36 h after the initiation of belinostat, as did global lysine acetylation, but returned to baseline 12 h after the end of infusion. The combination of B+C+E is safe and active in SCLC and other neuroendocrine cancers. Future phase II studies should consider genotyping patients for UGT1A1*28 and UGT1A1*60 and to identify patients at an increased risk of adverse events.

Estimation of tumour regression and growth rates during treatment in patients with advanced prostate cancer: a retrospective analysis.

BACKGROUND: We applied mathematical models to clinical trial data available at Project Data Sphere LLC (Cary, NC, USA), a non-profit universal access data-sharing warehouse. Our aim was to assess the rates of cancer growth and regression using the comparator groups of eight randomised clinical trials that enrolled patients with metastatic castration-resistant prostate cancer. METHODS: In this retrospective analysis, we used data from eight randomised clinical trials with metastatic castration-resistant prostate cancer to estimate the growth (g) and regression (d) rates of disease burden over time. Rates were obtained by applying mathematical models to prostate-specific antigen levels as the representation of tumour quantity. Rates were compared between study interventions (prednisone, mitoxantrone, and docetaxel) and off-treatment data when on-study treatment had been discontinued to understand disease behaviour during treatment and after discontinuation. Growth (g) was examined for association with a traditional endpoint (overall survival) and for its potential use as an endpoint to reduce sample size in clinical trials. FINDINGS: Estimates for g, d, or both were obtained in 2353 (88%) of 2678 patients with data available for analysis; g differentiated docetaxel (a US Food and Drug Administration-approved therapy) from prednisone and mitoxantrone and was predictive of overall survival in a landmark analysis at 8 months. A simulated sample size analysis, in which g was used as the endpoint, compared docetaxel data with mitoxantrone data and showed that small sample sizes were sufficient to achieve 80% power (16, 47, and 25 patients, respectively, in the three docetaxel comparator groups). Similar results were found when the mitoxantrone data were compared with the prednisone data (41, 39, and 41 patients in the three mitoxantrone comparator groups). Finally, after discontinuation of docetaxel therapy, median tumour growth (g) increased by nearly five times. INTERPRETATION: The application of mathematical models to existing clinical data allowed estimation of rates of growth and regression that provided new insights in metastatic castration-resistant prostate cancer. The availability of clinical data through initiatives such as Project Data Sphere, when combined with innovative modelling techniques, could greatly enhance our understanding of how cancer responds to treatment, and accelerate the productivity of clinical development programmes. FUNDING: None.

A Phase II Multi-Center Study of Bevacizumab in Combination with Ixabepilone in Subjects with Advanced Renal Cell Carcinoma.

LESSONS LEARNED: Accrual to renal cell carcinoma trials remains a challenge despite the lack of prolonged response to the available treatments.The observation of three responses among the 30 patients with median progression-free survival and overall survival of 8.3 and 15 months, respectively, indicates the combination has some activity, but it is not sufficient for further development. BACKGROUND: Treatment of metastatic renal cell carcinoma (mRCC) remains suboptimal. Preclinical data have previously shown that ixabepilone, a microtubule-stabilizing agent approved for the treatment of breast cancer, is active in taxane-sensitive and -resistant cells. In this single-arm phase II trial, we investigated a combination of ixabepilone plus bevacizumab in patients with refractory mRCC. METHODS: We enrolled 30 patients with histologically confirmed mRCC, clear cell subtype, who had not been previously treated with ixabepilone or bevacizumab but had received at least one prior U.S. Food and Drug Administration (FDA)-approved treatment for renal cell carcinoma (RCC). The treatment regimen consisted of 6 mg/m2 ixabepilone per day for 5 days and 15 mg/kg bevacizumab every 21 days. After 6 cycles, the treatment interval could be extended to every 28 days. The primary endpoint was the objective response rate according to the Response Evaluation Criteria in Solid Tumors (RECIST). Secondary endpoints were progression-free survival (PFS), overall survival (OS), and the toxicity of the combination. RESULTS: The median number of prior therapies was two (range per patient one to five). Patients received a median of 8 cycles of ixabepilone plus bevacizumab (range 2-54). The median follow-up was 36.4 months (range 23.5-96.5). Nineteen patients (63.3%) had stable disease as a best response. Three patients (10%) had a partial response. The median PFS was 8.3 months (95% confidence interval [CI], 4.9-10.6) and the median OS was 15.0 months (95% CI, 11.3-28.8). The total number of cycle for safety evaluation was 289. Grade 3/4 adverse events (>5% incidence) included lymphopenia (16.7%), hypertension (6.7%), and leukopenia (6.7%). CONCLUSION: The combination of ixabepilone and bevacizumab was well tolerated, with modest activity in second - or later-line mRCC, but it is not recommended as a therapy without further clinical development. Alternative combinations with these agents could be explored in future studies.

Precision oncology: origins, optimism, and potential.

Imatinib, the first and arguably the best targeted therapy, became the springboard for developing drugs aimed at molecular targets deemed crucial to tumours. As this development unfolded, a revolution in the speed and cost of genetic sequencing occurred. The result--an armamentarium of drugs and an array of molecular targets--set the stage for precision oncology, a hypothesis that cancer treatment could be markedly improved if therapies were guided by a tumour's genomic alterations. Drawing lessons from the biological basis of cancer and recent empirical investigations, we take a more measured view of precision oncology's promise. Ultimately, the promise is not our concern, but the threshold at which we declare success. We review reports of precision oncology alongside those of precision diagnostics and novel radiotherapy approaches. Although confirmatory evidence is scarce, these interventions have been widely endorsed. We conclude that the current path will probably not be successful or, at a minimum, will have to undergo substantive adjustments before it can be successful. For the sake of patients with cancer, we hope one form of precision oncology will deliver on its promise. However, until confirmatory studies are completed, precision oncology remains unproven, and as such, a hypothesis in need of rigorous testing.

Assessing the Eventual Publication of Clinical Trial Abstracts Submitted to a Large Annual Oncology Meeting.

BACKGROUND: Despite the ethical imperative to publish clinical trials when human subjects are involved, such data frequently remain unpublished. The objectives were to tabulate the rate and ascertain factors associated with eventual publication of clinical trial results reported as abstracts in the Proceedings of the American Society of Clinical Oncology (American Society of Clinical Oncology). MATERIALS AND METHODS: Abstracts describing clinical trials for patients with breast, lung, colorectal, ovarian, and prostate cancer from 2009 to 2011 were identified by using a comprehensive online database (http://meetinglibrary.asco.org/abstracts). Abstracts included reported results of a treatment or intervention assessed in a discrete, prospective clinical trial. Publication status at 4-6 years was determined by using a standardized search of PubMed. Primary outcomes were the rate of publication for abstracts of randomized and nonrandomized clinical trials. Secondary outcomes included factors influencing the publication of results. RESULTS: A total of 1,075 abstracts describing 378 randomized and 697 nonrandomized clinical trials were evaluated. Across all years, 75% of randomized and 54% of nonrandomized trials were published, with an overall publication rate of 61%. Sample size was a statistically significant predictor of publication for both randomized and nonrandomized trials (odds ratio [OR] per increase of 100 participants = 1.23 [1.11-1.36], p < .001; and 1.64 [1.15-2.34], p = .006, respectively). Among randomized studies, an industry coauthor or involvement of a cooperative group increased the likelihood of publication (OR 2.37, p = .013; and 2.21, p = .01, respectively). Among nonrandomized studies, phase II trials were more likely to be published than phase I (p < .001). Use of an experimental agent was not a predictor of publication in randomized (OR 0.76 [0.38-1.52]; p = .441) or nonrandomized trials (OR 0.89 [0.61-1.29]; p = .532). CONCLUSION: This is the largest reported study examining why oncology trials are not published. The data show that 4-6 years after appearing as abstracts, 39% of oncology clinical trials remain unpublished. Larger sample size and advanced trial phase were associated with eventual publication; among randomized trials, an industry-affiliated author or a cooperative group increased likelihood of publication. Unfortunately, we found that, despite widespread recognition of the problem and the creation of central data repositories, timely publishing of oncology clinical trials results remains unsatisfactory.

Are patients with hormonally functional phaeochromocytoma and paraganglioma initially receiving a proper adrenoceptor blockade? A retrospective cohort study.

OBJECTIVE: Pharmacological treatment is mandatory in patients with hormonally functional phaeochromocytoma and paraganglioma (PHAEO/PGL). We evaluated if patients initially diagnosed with hormonally functional PHAEO/PGL by various medical subspecialties received proper adrenoceptor blockade, and analysed factors predicting the prescription of adequate treatment. METHODS: In a retrospective cohort study, we reviewed data from patients initially diagnosed with hormonally functional PHAEO/PGL outside the National Institutes of Health and Cedars-Sinai Medical Center, who were referred to these institutions between January 2001 and April 2015. Logistic regression was used to assess factors associated with proper adrenoceptor blockade. RESULTS: A total of 381 patients were included. Adequate pharmacological treatment was prescribed to 69·3%, of which 93·1% received α-adrenoceptor blockers. Regarding patients who were inappropriately treated, 53% did not receive any medication. Independent predictors of the prescription of a proper blockade were the diagnosis by endocrinologists [odds ratio (OR) 4·14; 95% confidence interval (CI), 2·51-6·85; P < 0·001], the presence of high blood pressure (OR 5·94; 95% CI, 3·11-11·33; P < 0·001) and the evidence of metastasis (OR 5·96; 95% CI, 1·93-18·46; P = 0·002). CONCLUSIONS: Although most patients received adequate pharmacological treatment, almost one-third were either not treated or received inappropriate medications. The diagnosis by endocrinologists, the presence of high blood pressure and the evidence of metastatic disease were identified as independent predictors of a proper blockade. These results highlight the need to educate physicians about the importance of starting adequate adrenoceptor blockade in all patients with hormonally functional PHAEO/PGL.

CHARACTERISTICS AND OUTCOMES OF METASTATIC SDHB AND SPORADIC PHEOCHROMOCYTOMA/PARAGANGLIOMA: AN NATIONAL INSTITUTES OF HEALTH STUDY.

OBJECTIVE: Overall about 10 to 20% of pheochromocytomas/paragangliomas (PHEOs/PGLs) are metastatic, with higher metastatic potential observed in succinate dehydrogenase subunit B/fumarate hydratase (SDHB/FH)-related tumors. Due to the improved availability of biochemical and genetic testing and the frequent use of anatomical/functional imaging, there is currently a higher detection rate of metastatic PHEO/PGL. METHODS: A retrospective analysis of 132 patients (27 children, 105 adults) with metastatic PHEO/PGL diagnosed and treated from 2000 to 2014 was conducted. RESULTS: Seventy-seven (58%) males and 55 (42%) females were included; 39 (30%) have died, with no sex preference. Seventy-three (55%) patients had SDHB mutations; 59 (45%) patients had apparently sporadic tumors (AST). SDHB patients had an average age at primary tumor diagnosis of 31 ± 16 years compared to 40 ± 15 years in AST patients (P<.001). The average metastatic interval (MI) decreased with increasing age in both SDHB and AST patients (P = .013 for both). Only 16% of all primary tumors were smaller than 4.5 cm. Eleven percent of patients had biochemically silent disease, more with SDHB. Of SDHB patients, 23% had metastatic tumors at first diagnosis, compared to 15% of AST patients. Five- and 10-year survival rates were significantly better for metastatic AST than SDHB patients (P = .01). Overall survival was significantly different between children and adults (P = .037); this was mostly attributed to the SDHB patients, in whom children had statistically significantly longer survival than adults (P = .006). The deceased patients all died due to the PHEO/PGL and mainly had noradrenergic phenotypes. CONCLUSION: In children, metastatic PHEOs/PGLs are mainly due to SDHB mutations; in adults they are equally distributed between in SDHB mutations and AST, with better 5- and 10-year survival rates for ASTs. In SDHB patients, children survive longer than adults. Primary metastatic tumors, most presenting as noradrenergic PGLs, are larger than 4.5 cm in >80% of patients. The frequency of metastatic tumors from primary AST increases with age, including a decreased MI compared to SDHB tumors. These results support several recommendations that are summarized in the Discussion.