Evaluation of Tumor DNA Sequencing Results in Patients with Gastric and Gastroesophageal Junction Adenocarcinoma Stratified by TP53 Mutation Status.

BACKGROUND: Gastric cancer (GC) and gastroesophageal junction adenocarcinomas (GEJ) are molecularly diverse. TP53 is the most frequently altered gene with approximately 50% of patients harboring mutations. This qualitative study describes the distinct genomic alterations in GCs and GEJs stratified by TP53 mutation status. PATIENTS AND METHODS: Tumor DNA sequencing results of 324 genes from 3741 patients with GC and GEJ were obtained from Foundation Medicine. Association between gene mutation frequency and TP53 mutation status was examined using Fisher's exact test. Functional gene groupings representing molecular pathways suggested to be differentially mutated in TP53 wild-type (TP53WT) and TP53 mutant (TP53MUT) tumors were identified. The association of the frequency of tumors containing a gene mutation in the molecular pathways of interest and TP53 mutation status was assessed using Fisher's exact test with a P-value of <.01 deemed statistically significant for all analyses. RESULTS: TP53 mutations were noted in 61.6% of 2946 GCs and 81.4% of 795 GEJs (P < .001). Forty-nine genes had statistically different mutation frequencies in TP53WT vs. TP53MUT patients. TP53WT tumors more likely had mutations related to DNA mismatch repair, homologous recombination repair, DNA and histone methylation, Wnt/B-catenin, PI3K/Akt/mTOR, and chromatin remodeling complexes. TP53MUT tumors more likely had mutations related to fibroblast growth factor, epidermal growth factor receptor, other receptor tyrosine kinases, and cyclin and cyclin-dependent kinases. CONCLUSION: The mutational profiles of GCs and GEJs varied according to TP53 mutation status. These mutational differences can be used when designing future studies assessing the predictive ability of TP53 mutation status when targeting differentially affected molecular pathways.

Durable Progression-Free Survival With the Use of BRAF and MEK Inhibitors in Four Cases With BRAF V600E-Mutated Gliomas.

INTRODUCTION: BRAF V600 E mutations have been identified in a subset of patients with primary brain tumors. Combination therapy with BRAF and Mitogen-activated protein kinase (MEK) inhibitors (BRAF/MEKi) targeting sequential steps in the MAPK pathway has replaced BRAFi monotherapy as the standard of care in multiple tumors with BRAF V600 E mutations, and clinical evidence for this strategy continues to grow in primary brain tumors. CASE SERIES: We describe four patients with BRAF V600 E mutated gliomas, including a 21-year-old woman with a ganglioglioma WHO grade I, a 19-year-old man with a pleomorphic xanthoastrocytoma WHO grade III, and 21-year-old and 33-year-old women with epithelioid GBM WHO grade IV, who achieved durable progression-free survival with combination BRAF/MEKi. CONCLUSION: Combination of BRAF/MEK inhibition can be a novel, promising approach as targeted therapy in gliomas with BRAF V600 E mutations, especially those that are resistant to standard therapy. Our cases, along with other early reports utilizing dabrafenib/trametinib, highlight the importance of somatic next-generation sequencing, particularly in younger patients. Interim results from clinical trials utilizing dabrafenib/trametinib have been promising thus far, and our case series suggests that durable clinical benefit is possible, even in the setting of glioblastoma, WHO grade IV.

Clinical, pathological, and genomic features of EWSR1-PATZ1 fusion sarcoma.

Molecular diagnostics of sarcoma subtypes commonly involve the identification of characteristic oncogenic fusions. EWSR1-PATZ1 is a rare fusion partnering in sarcoma, with few cases reported in the literature. In the current study, a series of 11 cases of EWSR1-PATZ1 fusion positive malignancies are described. EWSR1-PATZ1-related sarcomas occur across a wide age range and have a strong predilection for chest wall primary site. Secondary driver mutations in cell-cycle genes, and in particular CDKN2A (71%), are common in EWSR1-PATZ1 sarcomas in this series. In a subset of cases, an extended clinical and histopathological review was performed, as was confirmation and characterization of the fusion breakpoint revealing a novel intronic pseudoexon sequence insertion. Unified by a shared gene fusion, EWSR1-PATZ1 sarcomas otherwise appear to exhibit divergent morphology, a polyphenotypic immunoprofile, and variable clinical behavior posing challenges for precise classification.

Response to Checkpoint Inhibitor Therapy in Advanced Classic Kaposi Sarcoma: A Case Report and Immunogenomic Study.

Kaposi sarcoma (KS) is an uncommon angioproliferative malignancy that is associated with human herpesvirus 8. Although there has been recent enthusiasm for evaluating immune checkpoint inhibition as a therapeutic option for viral-associated tumors, the clinical utility in this disease is currently unknown. We report a case of advanced classic KS refractory to multiple lines of chemotherapy that experienced a partial response to anti-PD-1 therapy. Comprehensive molecular profiling was performed on a diagnostic tumor biopsy sample. Molecular profiling data from 8 additional male patients with KS were reviewed and compared with those of the index case. The genomic profile of the index case was notable for higher-than-typical somatic mutational burden, including pathogenic mutation in multiple well-described cancer genes, such as TP53, CDKN2A, NOTCH1, and KRAS Our case suggests that further clinical study of checkpoint inhibitor therapy in classic KS is warranted, and provides a hypothesis for future immunogenomic biomarker analysis in this disease.

Comprehensive assessment of cytochromes P450 and transporter genetics with endoxifen concentration during tamoxifen treatment.

OBJECTIVES: Tamoxifen bioactivation to endoxifen is mediated primarily by CYP2D6; however, considerable variability remains unexplained. Our aim was to perform a comprehensive assessment of the effect of genetic variation in tamoxifen-relevant enzymes and transporters on steady-state endoxifen concentrations. PATIENTS AND METHODS: Comprehensive genotyping of CYP enzymes and transporters was performed using the iPLEX ADME PGx Pro Panel in 302 tamoxifen-treated breast cancer patients. Predicted activity phenotype for 19 enzymes and transporters were analyzed for univariate association with endoxifen concentration, and then adjusted for CYP2D6 and clinical covariates. RESULTS: In univariate analysis, higher activity of CYP2C8 (regression ß=0.22, P=0.020) and CYP2C9 (ß=0.20, P=0.04), lower body weight (ß=-0.014, P<0.0001), and endoxifen measurement during winter (each ß<-0.39, P=0.002) were associated with higher endoxifen concentrations. After adjustment for the CYP2D6 diplotype, weight, and season, CYP2C9 remained significantly associated with higher concentrations (P=0.02), but only increased the overall model R by 1.3%. CONCLUSION: Our results further support a minor contribution of CYP2C9 genetic variability toward steady-state endoxifen concentrations. Integration of clinician and genetic variables into individualized tamoxifen dosing algorithms would marginally improve their accuracy and potentially enhance tamoxifen treatment outcomes.

Pharmacoepidemiology of Clinically Relevant Hypothyroidism and Hypertension from Sunitinib and Sorafenib.

BACKGROUND: Thyroid dysfunction and hypertension (HTN) have been sporadically reported with sunitinib (SUN) and sorafenib (SOR). Determination of the side effect incidence will enhance monitoring and management recommendations. METHODS: An observational cohort study was performed using deidentified pharmacy claims data from a 3-year period to evaluate patients prescribed SUN, SOR, or capecitabine (CAP; comparison group). The primary outcome was time to first prescription for thyroid replacement or HTN treatment. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated by Cox proportional hazards models. RESULTS: A total of 20,061 patients were eligible for evaluation of thyroid replacement therapy, which was initiated in 11.6% of those receiving SUN (HR, 16.77; 95% CI, 13.54-20.76), 2.6% of those receiving SOR (HR, 3.47; 95% CI, 2.46-4.98), and 1% of those receiving CAP, with median time to initiation of 4 months (range, 1-35 months). A total of 14,468 patients were eligible for evaluation of HTN therapy, which was initiated in 21% of SUN recipients (HR, 4.91; 95% CI, 4.19-5.74), 14% of SOR recipients (HR, 3.25; 95% CI, 2.69-3.91), and 5% of CAP recipients, with median time to initiation of 1 month (range, 1-18 months) for SOR and 2 months (range, 1-25 months) for SUN. CONCLUSION: SUN and SOR significantly increased the risk for clinically relevant hypothyroidism; the risk was at least 4 times greater with SUN than with SOR. Patients receiving SUN and SOR had a similar elevated risk for clinically relevant HTN. These data provide robust measures of the incidence and time to onset of these clinically actionable adverse events. The Oncologist 2017;22:208-212Implications for Practice: The side effect profiles for novel therapies are typically used to create monitoring and management recommendations using clinical trial data from patient populations that may not represent those seen in standard clinical practice. This analysis using a large pharmacy claims database better reflects typical patients treated with sorafenib or sunitinib outside of a clinical trial. The findings of increased need for thyroid replacement in patients receiving sunitinib compared with sorafenib and a similar increase in need for hypertension therapy with both agents can be used to form clinically relevant monitoring recommendations for these agents.

Key Lessons Learned from Moffitt's Molecular Tumor Board: The Clinical Genomics Action Committee Experience.

BACKGROUND: The increasing practicality of genomic sequencing technology has led to its incorporation into routine clinical practice. Successful identification and targeting of driver genomic alterations that provide proliferative and survival advantages to tumor cells have led to approval and ongoing development of several targeted cancer therapies. Within many major cancer centers, molecular tumor boards are constituted to shepherd precision medicine into clinical practice. MATERIALS AND METHODS: In July 2014, the Clinical Genomics Action Committee (CGAC) was established as the molecular tumor board companion to the Personalized Medicine Clinical Service (PMCS) at Moffitt Cancer Center in Tampa, Florida. The processes and outcomes of the program were assessed in order to help others move into the practice of precision medicine. RESULTS: Through the establishment and initial 1,400 patients of the PMCS and its associated molecular tumor board at a major cancer center, five practical lessons of broad applicability have been learned: transdisciplinary engagement, the use of the molecular report as an aid to clinical management, clinical actionability, getting therapeutic options to patients, and financial considerations. Value to patients includes access to cutting-edge practice merged with individualized preferences in treatment and care. CONCLUSIONS: Genomic-driven cancer medicine is increasingly becoming a part of routine clinical practice. For successful implementation of precision cancer medicine, strategically organized molecular tumor boards are critical to provide objective evidence-based translation of observed molecular alterations into patient-centered clinical action. Molecular tumor board implementation models along with clinical and economic outcomes will define future treatment standards. The Oncologist 2017;22:144-151Implications for Practice: It is clear that the increasing practicality of genetic tumor sequencing technology has led to its incorporation as part of routine clinical practice. Subsequently, many cancer centers are seeking to develop a personalized medicine services and/or molecular tumor board to shepherd precision medicine into clinical practice. This article discusses the key lessons learned through the establishment and development of a molecular tumor board and personalized medicine clinical service. This article highlights practical issues and can serve as an important guide to other centers as they conceive and develop their own personalized medicine services and molecular tumor boards.

Novel and Expanded Oncology Drug Approvals of 2016-PART 1: New Options in Solid Tumor Management.

The nonradiologic medical management of solid tumors has evolved from the use of traditional cytotoxic agents to modern targeted therapies, monoclonal antibodies, and immunotherapies. Advances in the understanding of cancer biology and therapeutic strategies have resulted in increasing numbers of new drug applications and approvals. Consequently, practicing oncologists need to learn how the newly available agents function and what toxicities to watch for, as well as ways to optimize the use of both new drugs and previously approved drugs with new indications. In 2016, the US Food and Drug Administration approved three novel drugs for the treatment of solid malignancies-olaratumab in selected patients with soft-tissue sarcoma, atezolizumab for the treatment of bladder cancer, and rucaparib for the treatment of ovarian cancer; also in 2016, the use of previously approved anticancer agents (including atezolizumab) was expanded into 11 new patient populations. The diversity of options for patients is evident in the broad range of the 2016 approvals, which include immune checkpoint inhibitors, targeted therapies, monoclonal antibodies, and traditional cytotoxic agents. This article focuses on the new agents and indications that emerged in 2016 for solid tumor treatment. We review the drug indications, mechanisms of action, pivotal trial data, pertinent toxicities, use in special populations, and the appropriate clinical contexts for treatment planning.

Novel and Expanded Oncology Drug Approvals of 2016-PART 2: New Options in the Management of Hematologic Malignancies.

The recent past has brought pharmacotherapeutic advances that benefit patients with hematologic malignancies. In 2016, two novel hematology drugs were approved and four previously approved hematology drugs were granted expanded use for the treatment of appropriate patient populations by the US Food and Drug Administration. These new approvals and indications represent significant steps forward in patient management: they include the first-in-class B-cell lymphoma 2 inhibitor, venetoclax, the newest targeted therapy available for the treatment of hematologic malignancies; and nivolumab, the first immune checkpoint inhibitor to be approved for treatment of a hematologic malignancy. Other advances include defibrotide as the first drug approved for the treatment of veno-occlusive disease with evidence of multiorgan dysfunction, and the expansion of indications for the two anti-CD20 monoclonal antibodies ofatumumab and obinutuzumab, as well as the anti-CD38 monoclonal antibody daratumumab. This article reviews each of these drugs and their indications, mechanisms of action, accompanying pivotal trial data, pertinent toxicities, use in special populations, and appropriate clinical context.

Tamoxifen Dose Escalation in Patients With Diminished CYP2D6 Activity Normalizes Endoxifen Concentrations Without Increasing Toxicity.

BACKGROUND: Polymorphic CYP2D6 is primarily responsible for metabolic activation of tamoxifen to endoxifen. We previously reported that by increasing the daily tamoxifen dose to 40 mg/day in CYP2D6 intermediate metabolizer (IM), but not poor metabolizer (PM), patients achieve endoxifen concentrations similar to those of extensive metabolizer patients on 20 mg/day. We expanded enrollment to assess the safety of CYP2D6 genotype-guided dose escalation and investigate concentration differences between races. METHODS: PM and IM breast cancer patients currently receiving tamoxifen at 20 mg/day were enrolled for genotype-guided escalation to 40 mg/day. Endoxifen was measured at baseline and after 4 months. Quality-of-life data were collected using the Functional Assessment of Cancer Therapy-Breast (FACT-B) and Breast Cancer Prevention Trial Menopausal Symptom Scale at baseline and after 4 months. RESULTS: In 353 newly enrolled patients, genotype-guided dose escalation eliminated baseline concentration differences in IM (p = .08), but not PM (p = .009), patients. Endoxifen concentrations were similar in black and white patients overall (p = .63) and within CYP2D6 phenotype groups (p > .05). In the quality-of-life analysis of 480 patients, dose escalation did not meaningfully diminish quality of life; in fact, improvements were seen in several measures including the FACT Breast Cancer subscale (p = .004) and limitations in range of motion (p < .0001) in IM patients. CONCLUSION: Differences in endoxifen concentration during treatment can be eliminated by doubling the tamoxifen dose in IM patients, without an appreciable effect on quality of life. Validation of the association between endoxifen concentration and efficacy or prospective demonstration of improved efficacy is necessary to warrant clinical uptake of this personalized treatment strategy. IMPLICATIONS FOR PRACTICE: This secondary analysis of a prospective CYP2D6 genotype-guided tamoxifen dose escalation study confirms that escalation to 40 mg/day in patients with low-activity CYP2D6 phenotypes (poor or intermediate metabolizers) increases endoxifen concentrations without any obvious increases in treatment-related toxicity. It remains unknown whether endoxifen concentration is a useful predictor of tamoxifen efficacy, and thus, there is no current role in clinical practice for CYP2D6 genotype-guided tamoxifen dose adjustment. If future studies confirm the importance of endoxifen concentrations for tamoxifen efficacy and report a target concentration, this study provides guidance for a dose-adjustment approach that could maximize efficacy while maintaining patient quality of life.

In vivo assessment of the metabolic activity of CYP2D6 diplotypes and alleles.

AIMS: A prospectively enrolled patient cohort was used to assess whether the prediction of CYP2D6 phenotype activity from genotype data could be improved by reclassification of diplotypes or alleles. METHODS: Three hundred and fifty-five patients receiving tamoxifen 20 mg were genotyped for CYP2D6 and tamoxifen metabolite concentrations were measured. The endoxifen : N-desmethly-tamoxifen metabolic ratio, as a surrogate of CYP2D6 activity, was compared across four diplotypes (EM/IM, EM/PM, IM/IM, IM/PM) that are typically collapsed into an intermediate metabolizer (IM) phenotype. The relative metabolic activity of each allele type (UM, EM, IM, and PM) and each EM and IM allele was estimated for comparison with the activity scores typically assigned, 2, 1, 0.5 and 0, respectively. RESULTS: Each of the four IM diplotypes have distinct CYP2D6 activity from each other and from the EM and PM phenotype groups (each P < 0.05). Setting the activity of an EM allele at 1.0, the relative activities of a UM, IM and PM allele were 0.85, 0.67 and 0.52, respectively. The activity of the EM alleles were statistically different (P < 0.0001), with the CYP2D6*2 allele (scaled activity = 0.63) closer in activity to an IM than an EM allele. The activity of the IM alleles were also statistically different (P = 0.014). CONCLUSION: The current systems for translating CYP2D6 genotype into phenotype are not optimally calibrated, particularly in regards to IM diplotypes and the *2 allele. Additional research is needed to improve the prediction of CYP2D6 activity from genetic data for individualized dosing of CYP2D6 dependent drugs.

A community-based multicenter trial of pharmacokinetically guided 5-fluorouracil dosing for personalized colorectal cancer therapy.

BACKGROUND: Pharmacokinetically guided (PK-guided) versus body surface area-based 5-fluorouracil (5-FU) dosing results in higher response rates and better tolerability. A paucity of data exists on PK-guided 5-FU dosing in the community setting. PATIENTS AND METHODS: Seventy colorectal cancer patients, from one academic and five community cancer centers, received the mFOLFOX6 regimen (5-FU 2,400 mg/m(2) over 46 hours every 2 weeks) with or without bevacizumab at cycle 1. The 5-FU continuous-infusion dose was adjusted for cycles 2-4 using a PK-guided algorithm to achieve a literature-based target area under the concentration-time curve (AUC). The primary objective was to demonstrate that PK-guided 5-FU dosing improves the ability to achieve a target AUC within four cycles of therapy. The secondary objective was to demonstrate reduced incidence of 5-FU-related toxicities. RESULTS: At cycles 1 and 4, 27.7% and 46.8% of patients achieved the target AUC (20-25 mg × hour/L), respectively (odds ratio [OR]: 2.20; p = .046). Significantly more patients were within range at cycle 4 compared with a literature rate of 20% (p < .0001). Patients had significantly higher odds of not being underdosed at cycle 4 versus cycle 1 (OR: 2.29; p = .037). The odds of a patient being within range increased by 30% at each subsequent cycle (OR: 1.30; p = .03). Less grade 3/4 mucositis and diarrhea were observed compared with historical data (1.9% vs 16% and 5.6% vs 12%, respectively); however, rates of grade 3/4 neutropenia were similar (33% vs 25%-50%). CONCLUSION: PK-guided 5-FU dosing resulted in significantly fewer underdosed patients and less gastrointestinal toxicity and allows for the application of personalized colorectal cancer therapy in the community setting.

Rates of Renal Toxicity in Cancer Patients Receiving Cisplatin With and Without Mannitol.

BACKGROUND: Cisplatin is a widely used antineoplastic. One of the major complications of cisplatin use is dose-limiting nephrotoxicity. There are many strategies to prevent this toxicity, including the use of mannitol as a nephroprotectant in combination with hydration. OBJECTIVE: We aimed to evaluate the rates of cisplatin-induced nephrotoxicity in cancer patients receiving single-agent cisplatin with and without mannitol. METHODS: This single-center retrospective analysis was a quasi experiment created by the national mannitol shortage. Data were collected on adult cancer patients receiving single-agent cisplatin as an outpatient from January 2011 to September 2012. The primary outcome was acute kidney injury (AKI). RESULTS: We evaluated 143 patients who received single-agent cisplatin; 97.2% of patients had head and neck cancer as their primary malignancy. Patients who did not receive mannitol were more likely to develop nephrotoxicity: odds ratio [OR] = 2.646 (95% CI = 1.008, 6.944; P = 0.048). Patients who received the 100 mg/m2 dosing and patients who had a history of hypertension also had a higher likelihood of developing nephrotoxicity: OR = 11.494 (95% CI = 4.149, 32.258; P < 0.0001) and OR = 3.219 (95% CI = 1.228, 8.439; P = 0.017), respectively. CONCLUSIONS: When limited quantities of mannitol are available, it should preferentially be given to patients at particularly high risk of nephrotoxicity. Our analysis suggests that those patients receiving the dosing schedule of 100 mg/m2 cisplatin every 3 weeks and those with hypertension are at the greatest risk of nephrotoxicity and would benefit from the addition of mannitol.

Regorafenib: a novel multitargeted tyrosine kinase inhibitor for colorectal cancer and gastrointestinal stromal tumors.

OBJECTIVE: To review currently available literature on the oral multikinase inhibitor regorafenib and its role in the treatment of metastatic colorectal cancer (mCRC), and imatinib- and sunitinib-resistant gastrointestinal stromal tumors (GISTs). DATA SOURCES: A comprehensive literature search was performed of PubMed/MEDLINE and American Society of Clinical Oncology (ASCO) abstracts (through August 2013). STUDY SELECTION/DATA EXTRACTION: Preclinical pharmacological and phase I to III trials data analyzing regorafenib efficacy and safety in mCRC or imatinib- and sunitinib-resistant GIST patients were evaluated. All available English-language, peer-reviewed articles and ASCO abstracts with relevant information were reviewed. DATA SYNTHESIS: Regorafenib was approved for mCRC in September 2012 and for imatinib- and sunitinib-resistant GISTs in February 2013. Regorafenib is an inhibitor of stromal, angiogenic, and oncogenic receptor tyrosine kinases, as well as the RAF/MEK/ERK signaling pathway. Phase III CORRECT (Regorafenib Monotherapy for Previously Treated Metastatic Colorectal Cancer) trial data demonstrated an overall survival benefit for mCRC patients treated with regorafenib (6.4 vs 5.0 months; P = .0052). Phase III GRID (Gastrointestinal Stromal Tumors After Failure of Imatinib and Sunitinib) trial data revealed a progression-free survival benefit in imatinib- and sunitinib-resistant GIST patients (4.8 vs 0.9 months; P < .0001). Its adverse event (AE) profile is comparable to that of other multikinase inhibitors. The most commonly observed grade ≥3 AEs included hypertension, hand-foot skin reaction, rash, diarrhea, and fatigue. CONCLUSIONS: Regorafenib is a novel oral multikinase inhibitor that has shown promising results for patients with advanced, unresectable or metastatic treatment-refractory CRCs or imatinib- and sunitinib-resistant GISTs.

Pilot study of rosiglitazone as an in vivo probe of paclitaxel exposure.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: • Paclitaxel and rosiglitazone are primarily metabolized by CYP2C8 and their in vitro metabolism by human liver microsomes is correlated. Probe assays that quantify the in vivo activity of CYP enzymes which are important in drug metabolism have been developed for use in clinical pharmacology research. A probe of CYP2C8 that is easy to administer and interpret may be valuable for individualized dosing of paclitaxel. WHAT THIS STUDY ADDS: • This pilot study demonstrates for the first time that there is an in vivo correlation between paclitaxel and rosiglitazone exposure. The finding, that a single rosiglitazone plasma concentration after oral dosing may explain significant variance in paclitaxel exposure, suggests that rosiglitazone may satisfy the requirements of a clinically useful in vivo probe. However, it is acknowledged that there is a need for further studies evaluating the use of rosiglitazone as a CYP2C8 probe and quantifying the relationship, in order to guide dosing of narrow therapeutic index drugs metabolized primarily by CYP2C8, such as paclitaxel. AIMS: To evaluate the use of rosiglitazone and the erythromycin breath test (ERMBT), as probes of CYP2C8 and CYP3A4, respectively, to explain inter-individual variability in paclitaxel exposure. METHODS: The concentration of rosiglitazone at 3 h and ERMBT results were included in a regression model to explain the variability in paclitaxel exposure in 14 subjects. RESULTS: Rosiglitazone concentration was significantly correlated with paclitaxel exposure (P= 0.018) while ERMBT had no predictive value (P= 0.47). CONCLUSIONS: The correlation between the exposure of rosiglitazone and paclitaxel likely reflects mutual dependence on the activity of CYP2C8. Rosiglitazone or similar agents may have value as in vivo probes of CYP2C8 activity.

Sylatron: a pegylated interferon for use in melanoma.

OBJECTIVE: To review the currently available literature on peginterferon alfa-2b (pegIFN [Sylatron]), including its role in therapy and toxicity for adjuvant treatment of locally advanced melanoma. DATA SOURCES: A literature search was performed of PubMed and the American Society of Clinical Oncology abstracts from 1976 to February 2012, using the primary search terms peginterferon alfa-2b, interferon, Sylatron, and melanoma. STUDY SELECTION AND DATA EXTRACTION: All available English-language articles and trials that described the pharmacology, pharmacokinetics, pharmacodynamics, clinical activity, or safety profile of pegIFN were reviewed. DATA SYNTHESIS: PegIFN was approved in March 2011 for the adjuvant treatment of node-positive melanoma. Interferon (IFN) is commonly used in patients with melanoma who remain at high risk for relapse following surgery; however, the optimal scheduling and dose are not agreed upon. Pegylation of IFN involves conjugation with polyethylene glycol. Following subcutaneous injection of pegIFN, the rate of absorption, renal and cellular clearance, and immunogenicity are reduced. As a result of the extended serum half-life, once-weekly administration is feasible, compared with the daily and/or thrice weekly dosing of IFN. When compared with observation alone in patients with resected stage III melanoma, pegIFN demonstrated a significant increase in relapse-free survival, with a marginal impact on overall survival. The most common adverse events were as expected with IFN and included fatigue, increased liver enzymes, pyrexia, headache, anorexia, myalgia, nausea, chills, depression, and injection site reactions. A large Phase 3 study is underway to further assess outcome and toxicity differences between pegIFN weekly and low-dose IFN thrice weekly. CONCLUSIONS: PegIFN is a modified version of the previously approved interferon indicated for the adjuvant treatment of melanoma. Although the safety profile remains similar between the pegylated and non-pegylated forms, once-weekly administration is feasible secondary to an extended serum half-life and may have improved convenience for the patient.

Human Epidermal Growth Factor Receptor 2-Targeting Approaches for Colorectal Cancer: Clinical Implications of Novel Treatments and Future Therapeutic Avenues.

The treatment paradigm for colorectal cancer (CRC) has changed significantly over the past decade with targeted therapeutics. Human epidermal growth factor receptor 2 (HER2) amplification is seen among 3%-4% of patients with metastatic CRC (mCRC). The biological discovery of HER2 amplification in cancer cells has led to practice-changing drug development for several solid tumors, including breast, gastric, and esophageal cancers. HER2 amplification is now highly actionable in CRC with distinct therapeutic combinations, including the combination of monoclonal antibodies and HER2 receptor-specific tyrosine kinase inhibitors, as well as antibody-drug conjugates, that delivers targeted cytotoxic agents. However, it is essential to define the therapeutic role and sequence of these different combinations, some of which are already part of standard clinical practice. In this review article, we discuss recent clinical studies demonstrating the clinical benefits of each distinct therapeutic approach and their impacts on the current management of HER2-amplified mCRC. We also review ongoing clinical trials targeting the HER2 pathway in mCRC and elaborate on novel therapeutic opportunities in this space that may further define the changing paradigm of HER2-targeted therapy for CRC.

Response to degarelix after resistance to luteinizing hormone-releasing hormone agonist therapy for metastatic prostate cancer.

Androgen deprivation with a luteinizing hormone-releasing hormone (LH-RH) agonist is the standard treatment for patients with metastatic prostate cancer who prefer nonsurgical options. Therapy with these agents is usually successful in achieving and maintaining castrate levels (< 50 ng/dl) of serum testosterone, but failures have been reported in up to 10% of patients. Traditionally, these patients are offered surgical castration with bilateral orchiectomy. However, the novel LH-RH antagonists may offer a nonsurgical alternative. We describe two patients with advanced prostate cancer who failed to achieve castrate levels of testosterone while on an LH-RH agonist, but subsequently responded to the LH-RH antagonist, degarelix. The first patient is a 63-year-old man who was treated with leuprolide for metastatic prostate cancer. He initially responded with prostate-specific antigen (PSA) that fell to 0.6 ng/ml. However, after 15 months of therapy, his PSA rose to 18.3 ng/ml and his testosterone was noted to be 208 ng/dl. He was switched to degarelix, and 4 weeks later his testosterone was adequately suppressed at 16 ng/dl. The second patient is a 41-year-old man with metastatic prostate cancer who was started on leuprolide, but after 3 months of therapy, was found to have a rising PSA and a testosterone of 96 ng/dl. Four weeks after switching to degarelix, his testosterone was 18 ng/dl and his PSA decreased concordantly. With continued monthly injections of degarelix, his testosterone has consistently remained to be at less than 20 ng/dl over 7 months of follow-up.

Developing Drugs for Tissue-Agnostic Indications: A Paradigm Shift in Leveraging Cancer Biology for Precision Medicine.

Targeted therapies have reshaped the landscape of the development of cancer therapeutics. Recent biomarker-driven, tissue-agnostic clinical trials represent a significant paradigm shift in precision cancer medicine. Despite their growth in preclinical and clinical studies, to date only a few biomarker-driven, tissue-agnostic indications have seen approval by the US Food and Drug Administration (FDA). These approvals include pembrolizumab in microsatellite instability-high or mismatch repair deficient solid tumors, as well as both larotrectinib and entrectinib in NTRK fusion-positive tumors. Complex cancer biology, clinical trial design, and identification of resistance mechanisms represent some of the challenges that future tissue-agnostic therapies have to overcome. In this Review, we present a brief history of the development of tissue-agnostic therapies, comparing the similarities in the approval of pembrolizumab, larotrectinib, and entrectinib for tissue-agnostic indications. We also explore the future of tissue-agnostic cancer therapeutics while identifying important challenges for the future that drugs targeting tissue-agnostic indications will face.

Identification of Targetable Gene Fusions and Structural Rearrangements to Foster Precision Medicine in KRAS Wild-Type Pancreatic Cancer.

It has recently been described that alternative oncogenic drivers may be found in KRAS wild-type (KRAS WT) pancreatic cancers. This study aimed to determine the incidence of targetable gene fusions present in KRAS WT pancreatic adenocarcinoma and response to targeted therapy. METHODS: One hundred consecutive patients with pancreatic adenocarcinoma who underwent targeted next-generation sequencing using DNA sequencing with RNA sequencing (n = 47) or without RNA sequencing (n = 53) at a single institution were included in the study. The frequency and landscape of targetable fusions in KRAS WT pancreatic adenocarcinoma was characterized and compared with the frequency of fusions in KRAS-mutated (KRAS MUT) pancreatic adenocarcinoma. Results were validated in two independent cohorts using data from AACR GENIE (n = 1,252) and TCGA (n = 150). The clinical history of fusion-positive patients who received targeted treatment is described. RESULTS: Pancreatic cancers from 13 of 100 patients (13%) were found to be KRAS WT. Targetable fusions were identified in 4/13 (31%) KRAS WT tumors compared with 0/87 (0%) KRAS MUT pancreatic adenocarcinomas (P = .0002). One patient with a novel MET fusion had a complete response to targeted therapy with crizotinib that is ongoing at 12+ months of treatment. In the validation cohorts, gene fusions were identified in 18/97 (19%) and 2/10 (20%) KRAS WT tumors reported in the AACR GENIE and TCGA cohorts, respectively. CONCLUSION: Oncogene fusions are present in KRAS WT pancreatic adenocarcinomas at an increased frequency when compared with KRAS MUT pancreatic adenocarcinomas. As these fusions may be susceptible to targeted therapy, molecular analyses for the detection of fusions in KRAS WT pancreatic adenocarcinomas may warrant increased consideration.