Safety And Efficacy Of Combination Lurbinectedin Plus Doxorubicin From A Phase 1b Trial In Patients With Advanced/Metastatic Soft Tissue Sarcoma.

PURPOSE: While cytotoxic chemotherapy is standard first-line treatment for patients with metastatic soft tissue sarcoma (STS), clinical outcomes remain suboptimal. Our prior study showed lurbinectedin plus doxorubicin is well-tolerated with promising clinical activity in STS. We designed this phase 1b trial to optimize dosing as the basis for a randomized trial in leiomyosarcoma (LMS) and to further explore the safety profile and efficacy signal. PATIENTS AND METHODS: Patients had advanced/metastatic STS and no prior anthracycline/lurbinectedin/trabectedin. Escalation followed a 3+3 design with 3-week cycles: lurbinectedin (3.2 mg/m2 day 1) and two doxorubicin levels (DL1: 25 mg/m2 day 1; DL2 25 mg/m2 days 1 and 8). The primary objectives were to identify the maximum tolerated dose (MTD) and recommended dose for subsequent randomized trials. RESULTS: Ten patients were enrolled in a 6-month period. The most common treatment-emergent adverse events (TEAE) were grade (G) 2 fatigue and nausea, and G2 cytopenias with no febrile neutropenia events. There were 2 dose-limiting toxicities (DLTs) at DL2 (day 8 [G2 ALT/AST increase, G3 neutropenia]), and 1 DLT in DL1 (G3 ALT increase). These were reversible and all patients continued the study. DL1 was chosen for further study. At the time of data cutoff, the estimated median PFS is 16.5 months (95%CI 6.0-ND). The ORR was 60% (6/10 confirmed partial responses [PR]). CONCLUSIONS: In this phase 1b study, the recommended dose is lurbinectedin 3.2 mg/m2 in combination with doxorubicin 25 mg/m2 every 3 weeks. The study combination was well-tolerated and demonstrated intriguing clinical activity.

Phase II Study of Eribulin plus Pembrolizumab in Metastatic Soft-tissue Sarcomas: Clinical Outcomes and Biological Correlates.

PURPOSE: Eribulin modulates the tumor-immune microenvironment via cGAS-STING signaling in preclinical models. This non-randomized phase II trial evaluated the combination of eribulin and pembrolizumab in patients with soft-tissue sarcomas (STS). PATIENTS AND METHODS: Patients enrolled in one of three cohorts: leiomyosarcoma (LMS), liposarcomas (LPS), or other STS that may benefit from PD-1 inhibitors, including undifferentiated pleomorphic sarcoma (UPS). Eribulin was administered at 1.4 mg/m2 i.v. (days 1 and 8) with fixed-dose pembrolizumab 200 mg i.v. (day 1) of each 21-day cycle, until progression, unacceptable toxicity, or completion of 2 years of treatment. The primary endpoint was the 12-week progression-free survival rate (PFS-12) in each cohort. Secondary endpoints included the objective response rate, median PFS, safety profile, and overall survival (OS). Pretreatment and on-treatment blood specimens were evaluated in patients who achieved durable disease control (DDC) or progression within 12 weeks [early progression (EP)]. Multiplexed immunofluorescence was performed on archival LPS samples from patients with DDC or EP. RESULTS: Fifty-seven patients enrolled (LMS, n = 19; LPS, n = 20; UPS/Other, n = 18). The PFS-12 was 36.8% (90% confidence interval: 22.5-60.4) for LMS, 69.6% (54.5-89.0) for LPS, and 52.6% (36.8-75.3) for UPS/Other cohorts. All 3 patients in the UPS/Other cohort with angiosarcoma achieved RECIST responses. Toxicity was manageable. Higher IFNα and IL4 serum levels were associated with clinical benefit. Immune aggregates expressing PD-1 and PD-L1 were observed in a patient that completed 2 years of treatment. CONCLUSIONS: The combination of eribulin and pembrolizumab demonstrated promising activity in LPS and angiosarcoma.

Image-guided percutaneous ablation of hepatic epithelioid hemangioendothelioma.

PURPOSE: Disease control and survival following percutaneous ablation of hepatic epithelioid hemangioendothelioma (EHE) was studied retrospectively. METHODS: Six patients underwent 16 image-guided ablation procedures to treat 35 liver tumors from 2015 to 2022 (17 microwave ablation, 9 irreversible electroporation, 8 cryoablation, and 1 radiofrequency ablation). Technical success, local progression, intrahepatic progression, distant progression, overall survival, and adverse events were assessed. RESULTS: Four of six (67%) patients were treatment naïve prior to ablation. The mean length of imaging follow-up from first ablation procedure was 43.0 ± 31.2 months. Thirty-three of 35 (94.3%) ablated tumors did not progress locally. Three of 6 patients (50%) had new intrahepatic progression and underwent repeat ablation or systemic treatment. No extrahepatic progression was observed. One patient died from EHE 2.7 years after initial diagnosis. No severe adverse events occurred. CONCLUSION: Percutaneous ablation is feasible, often in a staged fashion, and may provide favorable intermediate to long-term disease control for patients with hepatic EHE.

SAR-096: Phase II Clinical Trial of Ribociclib in Combination with Everolimus in Advanced Dedifferentiated Liposarcoma (DDL) and Leiomyosarcoma (LMS).

PURPOSE: Dedifferentiated liposarcoma (DDL) and leiomyosarcoma (LMS) are two common subtypes of soft-tissue sarcoma, a rare group of diseases for which new treatments are needed. Chemotherapy remains the standard option for advanced disease. Targeting cyclin-dependent kinase 4 and 6 (CDK4/6) in DDL and mTOR in LMS is of biologic interest. When combined, the CDK4 inhibitor ribociclib and the mTOR inhibitor everolimus have shown synergistic growth inhibition in multiple tumor models, suggesting that this combination could be beneficial in patients. PATIENTS AND METHODS: This was a single arm, open label, multicenter phase II study of the combination of ribociclib and everolimus. Patients were enrolled into one of two cohorts: DDL or LMS with intact Rb. The primary endpoint was progression-free rate (PFR) at 16 weeks. Secondary endpoints included progression-free survival (PFS) and overall survival, safety and biomarker analyses. RESULTS: In the DDL cohort, 33.3% [95% confidence interval (CI), 15.6%-55.3%] of patients were progression-free at 16 weeks. Median PFS in this cohort was 15.4 weeks (95% CI, 8-36 weeks) with 2 partial responses. In the LMS cohort the PFR at 16 weeks was 29.2% (95% CI, 12.6%-51.1%). Median PFS in this cohort was 15.7 weeks (95% CI, 7.7-NA). Most common toxicities included fatigue (66.7%), anorexia (43.8%), and hyperglycemia (43.8%). Concordance between Rb testing methodologies was poor. CONCLUSIONS: The combination of ribociclib and everolimus demonstrates activity in DDL with prolonged stable disease (≥16 weeks) meeting the primary endpoint. Notably partial responses were observed. The primary endpoint was not reached in the LMS cohort. The combination was well tolerated with expected side effects.

Atezolizumab for Advanced Alveolar Soft Part Sarcoma.

BACKGROUND: Alveolar soft part sarcoma (ASPS) is a rare soft-tissue sarcoma with a poor prognosis and no established therapy. Recently, encouraging responses to immune checkpoint inhibitors have been reported. METHODS: We conducted an investigator-initiated, multicenter, single-group, phase 2 study of the anti-programmed death ligand 1 (PD-L1) agent atezolizumab in adult and pediatric patients with advanced ASPS. Atezolizumab was administered intravenously at a dose of 1200 mg (in patients ≥18 years of age) or 15 mg per kilogram of body weight with a 1200-mg cap (in patients <18 years of age) once every 21 days. Study end points included objective response, duration of response, and progression-free survival according to Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1, as well as pharmacodynamic biomarkers of multistep drug action. RESULTS: A total of 52 patients were evaluated. An objective response was observed in 19 of 52 patients (37%), with 1 complete response and 18 partial responses. The median time to response was 3.6 months (range, 2.1 to 19.1), the median duration of response was 24.7 months (range, 4.1 to 55.8), and the median progression-free survival was 20.8 months. Seven patients took a treatment break after 2 years of treatment, and their responses were maintained through the data-cutoff date. No treatment-related grade 4 or 5 adverse events were recorded. Responses were noted despite variable baseline expression of programmed death 1 and PD-L1. CONCLUSIONS: Atezolizumab was effective at inducing sustained responses in approximately one third of patients with advanced ASPS. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT03141684.).

Phase 2 trial of palbociclib and ganitumab in patients with relapsed Ewing sarcoma.

BACKGROUND: Ewing sarcoma (EWS) is an aggressive sarcoma with few treatment options for patients with relapsed disease. Cyclin-dependent kinase 4 (CDK4) is a genomic vulnerability in EWS that is synergistic with IGF-1R inhibition in preclinical studies. We present the results of a phase 2 study combining palbociclib (CDK4/6 inhibitor) with ganitumab (IGF-1R monoclonal antibody) for patients with relapsed EWS. PATIENTS AND METHODS: This open-label, non-randomized, phase 2 trial enrolled patients ≥12 years with relapsed EWS. All patients had molecular confirmation of EWS and RECIST measurable disease. Patients initially received palbociclib 125 mg orally on Days 1-21 and ganitumab 18 mg/kg intravenously on Days 1 and 15 of a 28-day cycle. The primary endpoints were objective response (complete or partial) per RECIST and toxicity by CTCAE. An exact one-stage design required ≥4 responders out of 15 to evaluate an alternative hypothesis of 40% response rate against a null of 10%. The study was closed following enrollment of the 10th patient due to discontinuation of ganitumab supply. RESULTS: Ten evaluable patients enrolled [median age 25.7 years (range 12.3-40.1)]. The median duration of therapy was 2.5 months (range 0.9-10.8). There were no complete or partial responders. Three of 10 patients had stable disease for >4 cycles and 2 had stable disease at completion of planned therapy or study closure. Six-month progression-free survival was 30% (95% CI 1.6%-58.4%). Two patients had cycle 1 hematologic dose-limiting toxicities (DLTs) triggering palbociclib dose reduction to 100 mg daily for 21 days. Two subsequent patients had cycle 1 hematologic DLTs at the reduced dose. Eighty percent of patients had grade 3/4 AEs, including neutropenia (n = 8), white blood cell decreased (n = 7), and thrombocytopenia (n = 5). Serum total IGF-1 significantly increased (p = 0.013) and ctDNA decreased during the first cycle. CONCLUSIONS: This combination lacks adequate therapeutic activity for further study, though a subset of patients had prolonged stable disease.

Nirogacestat, a γ-Secretase Inhibitor for Desmoid Tumors.

BACKGROUND: Desmoid tumors are rare, locally aggressive, highly recurrent soft-tissue tumors without approved treatments. METHODS: We conducted a phase 3, international, double-blind, randomized, placebo-controlled trial of nirogacestat in adults with progressing desmoid tumors according to the Response Evaluation Criteria in Solid Tumors, version 1.1. Patients were assigned in a 1:1 ratio to receive the oral γ-secretase inhibitor nirogacestat (150 mg) or placebo twice daily. The primary end point was progression-free survival. RESULTS: From May 2019 through August 2020, a total of 70 patients were assigned to receive nirogacestat and 72 to receive placebo. Nirogacestat had a significant progression-free survival benefit over placebo (hazard ratio for disease progression or death, 0.29; 95% confidence interval, 0.15 to 0.55; P<0.001); the likelihood of being event-free at 2 years was 76% with nirogacestat and 44% with placebo. Between-group differences in progression-free survival were consistent across prespecified subgroups. The percentage of patients who had an objective response was significantly higher with nirogacestat than with placebo (41% vs. 8%; P<0.001), with a median time to response of 5.6 months and 11.1 months, respectively; the percentage of patients with a complete response was 7% and 0%, respectively. Significant between-group differences in secondary patient-reported outcomes, including pain, symptom burden, physical or role functioning, and health-related quality of life, were observed (P≤0.01). Frequent adverse events with nirogacestat included diarrhea (in 84% of the patients), nausea (in 54%), fatigue (in 51%), hypophosphatemia (in 42%), and maculopapular rash (in 32%); 95% of adverse events were of grade 1 or 2. Among women of childbearing potential receiving nirogacestat, 27 of 36 (75%) had adverse events consistent with ovarian dysfunction, which resolved in 20 women (74%). CONCLUSIONS: Nirogacestat was associated with significant benefits with respect to progression-free survival, objective response, pain, symptom burden, physical functioning, role functioning, and health-related quality of life in adults with progressing desmoid tumors. Adverse events with nirogacestat were frequent but mostly low grade. (Funded by SpringWorks Therapeutics; DeFi ClinicalTrials.gov number, NCT03785964.).

Real-world outcomes of patients with locally advanced or metastatic epithelioid sarcoma.

BACKGROUND: Limited data are available on the real-world effectiveness and safety of systemic therapies for advanced (surgically unresectable and/or metastatic) epithelioid sarcoma (ES). METHODS: A retrospective medical records review was conducted in patients with advanced ES who were initiating first-line or ≥2 lines of systemic therapy (2000-2017) at 5 US cancer centers. The real-world overall response rate (rwORR), the duration of response (rwDOR), the disease control rate (rwDCR) (defined as stable disease for ≥32 weeks or any duration of response), and progression-free survival (rwPFS) were assessed by radiology reports. Overall survival (OS), rwDOR, and rwPFS were estimated from the time therapy was initiated using the Kaplan-Meier method. Serious adverse events were assessed. RESULTS: Of 74 patients (median age at diagnosis, 33 years; range, 10.6-76.3 years), 72% were male, and 85% had metastatic disease. The median number of lines of therapy was 2 (range, 1-7 lines of therapy), and 46 patients (62%) received ≥2 lines of systemic therapy. First-line regimens were usually anthracycline-based (54%) or gemcitabine-based (24%). For patients receiving first-line systemic therapy, the rwORR was 15%, the rwDCR was 20%, the median rwDOR was 3.3 months (95% CI, 2.1-5.2 months), the median rwPFS was 2.5 months (95% CI, 1.7, 6.9 months), and the median OS was 15.2 months (95% CI, 11.4-21.7 months). For those who received ≥2 lines of systemic therapy, the rwORR was 9%, the rwDCR was 20%, the median rwDOR was 4.5 months (95% CI, 0.7-5.6 months), and the median rwPFS was 6.0 months (95% CI, 3.2-7.4 months). Over one-half of patients (51.4%) experienced an adverse event, most frequently febrile neutropenia (14%), pain (10%), anemia, dyspnea, fever, thrombocytopenia, or transaminitis (5% each). CONCLUSIONS: Systemic therapies demonstrate limited efficacy in patients with advanced ES and have associated toxicities.

The Angiosarcoma Project: enabling genomic and clinical discoveries in a rare cancer through patient-partnered research.

Despite rare cancers accounting for 25% of adult tumors1, they are difficult to study due to the low disease incidence and geographically dispersed patient populations, which has resulted in significant unmet clinical needs for patients with rare cancers. We assessed whether a patient-partnered research approach using online engagement can overcome these challenges, focusing on angiosarcoma, a sarcoma with an annual incidence of 300 cases in the United States. Here we describe the development of the Angiosarcoma Project (ASCproject), an initiative enabling US and Canadian patients to remotely share their clinical information and biospecimens for research. The project generates and publicly releases clinically annotated genomic data on tumor and germline specimens on an ongoing basis. Over 18 months, 338 patients registered for the ASCproject, which comprises a large proportion of all patients with angiosarcoma. Whole-exome sequencing (WES) of 47 tumors revealed recurrently mutated genes that included KDR, TP53, and PIK3CA. PIK3CA-activating mutations were observed predominantly in primary breast angiosarcoma, which suggested a therapeutic rationale. Angiosarcoma of the head, neck, face and scalp (HNFS) was associated with a high tumor mutation burden (TMB) and a dominant ultraviolet damage mutational signature, which suggested that for the subset of patients with angiosarcoma of HNFS, ultraviolet damage may be a causative factor and that immune checkpoint inhibition may be beneficial. Medical record review revealed that two patients with HNFS angiosarcoma had received off-label therapeutic use of antibody to the programmed death-1 protein (anti-PD-1) and had experienced exceptional responses, which highlights immune checkpoint inhibition as a therapeutic avenue for HNFS angiosarcoma. This patient-partnered approach has catalyzed an opportunity to discover the etiology and potential therapies for patients with angiosarcoma. Collectively, this proof-of-concept study demonstrates that empowering patients to directly participate in research can overcome barriers in rare diseases and can enable discoveries.

A phase II multi-strata study of lurbinectedin as a single agent or in combination with conventional chemotherapy in metastatic and/or unresectable sarcomas.

Chemotherapy objective response rates (ORRs) in metastatic soft tissue sarcoma (STS) are typically 20-40% with median progression-free survival (PFS) less than 6 months. Lurbinectedin is a new anticancer agent under investigation. The primary objective of this three-arm, phase II study was to determine the disease control rate (DCR = ORR + stable disease [SD]) at 24 weeks of lurbinectedin alone or with chemotherapy in STS. Eligible patients included adults with ≤2 prior cytotoxic therapies. Study cohorts were: stratum A (StrA; anthracycline-naive), lurbinectedin/doxorubicin; stratum B (StrB; prior anthracycline), lurbinectedin/gemcitabine; stratum C (StrC; prior anthracycline/gemcitabine) lurbinectedin monotherapy. Each stratum was analysed separately by Simon two-stage design. Forty-two patients were accrued (StrA = 20, StrB = 10, StrC = 12) including leiomyosarcoma [LMS] (n = 20), synovial sarcoma [SS](n = 4), malignant peripheral nerve sheath tumour (n = 3) and other STS histologies (n = 15). For StrA there were seven partial responses (PR) plus one stable disease (SD) at 24 weeks. For StrB, two patients met the 24-week DCR including one PR (leiomyosarcoma) and one SD (desmoplastic small round cell tumour [DSRCT]). StrB did not continue to the second stage. In StrC, no patients met the primary end-point. Median progression-free survival (PFS) was: StrA = 4.2 months (90% CI 1.4-7.8), StrB = 1.7 months (90% confidence interval (CI) 1.0-7.4), and StrC = 1.3 months (90% CI 1.1-3.0). Lurbinectedin as a single agent or with chemotherapy was well tolerated with haematologic adverse events (AE's) as the most common toxicity. There were no treatment-related deaths. The combination of lurbinectedin/doxorubicin reached the DCR end-point with seven PR and one patient with SD (ORR 35.0%, 24-week DCR 40.0%). Evidence of drug benefit was seen in leiomyosarcoma, dedifferentiated liposarcoma (DDLS), myxoid liposarcoma (MLS), synovial sarcoma (SS), and desmoplastic small round cell tumour (DSRCT). TRIAL REGISTRATION: clinicaltrials.gov; NCT02448537.

Immunotherapy with single agent nivolumab for advanced leiomyosarcoma of the uterus: Results of a phase 2 study.

BACKGROUND: Immunotherapy has changed the therapeutic landscape in oncology. Advanced uterine leiomyosarcoma (ULMS) remains an incurable disease in most cases, and despite new drug approvals, improvements in overall survival have been modest at best. The goal of this study was to evaluate programmed-death 1 (PD-1) inhibition with nivolumab in this patient population. METHODS: This single-center phase 2 trial completed enrollment between May and October 2015. Patients received 3 mg/kg of intravenous nivolumab on day 1 of each 2-week cycle until disease progression or unacceptable toxicity. The primary endpoint was objective response rate. We assessed PD-1, PD-ligand 1 (PD-L1), and PD-L2 expression in archival tumor samples and variations in immune-phenotyping of circulating immune cells during treatment. RESULTS: Twelve patients were enrolled in the first stage of the 2-stage design. A median of 5 (range, 2-6) 2-week cycles of nivolumab were administered. Of the 12 patients, none responded to treatment. The overall median progression-free survival was 1.8 months (95% confidence interval, 0.8-unknown). The study did not open the second stage due to lack of benefit as defined by the statistical plan. Archival samples were available for 83% of patients. PD-1 (>3% of cells), PD-L1, and PD-L2 (>5% and >10% of tumor cells, respectively) expression were observed in 20%, 20%, and 90% of samples, respectively. No significant differences were observed between pre- and posttreatment cell phenotypes. CONCLUSION: Single-agent nivolumab did not demonstrate a benefit in this cohort of previously treated advanced ULMS patients. Further biomarker-driven approaches and studies evaluating combined immune checkpoint-modulators should be considered. Cancer 2017;123:3285-90. © 2017 American Cancer Society.

The relation between cigarette smoking and risk of acute myeloid leukemia: an updated meta-analysis of epidemiological studies.

Smoking has been postulated as an environmental risk factor for acute myeloid leukemia (AML). The primary objective of this meta-analysis of observational studies was to evaluate the epidemiologic relationship between smoking and the risk of development of AML. Twenty-three studies published between January 1993 and December 2013 were included in our analysis, and accounted for 7,746 cases of AML. The outcome of interest was the relative risk (RR) with 95% confidence interval (CI) of developing AML in adult cigarette smokers in comparison with non-smokers, and was estimated using the random-effects model. Our results showed that current and ever smokers have 40% (RR 1.40, 95% CI 1.22-1.60; P < 0.001) and 25% (RR 1.25, 95% CI 1.15-1.36; P < 0.001) increased risk of developing AML when compared with non-smokers. The increased RR of AML was increased regardless of sex, study design, geographical region, and quality of the studies. Intensity of smoking of <10, 10-20, 20-30, and >30 cigarettes per day was associated with RRs of AML of 1.27, 1.36, 1.55, and 1.77, respectively (P < 0.001 for trend). Duration of smoking of <20 and >20 years was associated with RRs of 1.07 and 1.44, respectively (P < 0.001 for trend). Cumulative smoking of <10, 10-20, 20-30, and >30 pack-years was associated with RRs of 1.13, 1.23, 1.39, and 1.71, respectively (P < 0.001 for trend). Overall, cigarette smoking proves to be a significant risk factor for the development of AML in adults.

Cetuximab, paclitaxel, carboplatin, and radiation for head and neck cancer: a survival analysis of a Brown University Oncology Group phase II study.

OBJECTIVES: To assess the effect on progression-free and overall survival from the addition of cetuximab to paclitaxel-based chemoradiation for patients with squamous cell head and neck cancer from Brown University Oncology Group studies. METHODS: BrUOG HN-204 patients with stage III or IV locally advanced squamous cell cancer of the head and neck without distant organ metastases received 4 weeks of induction cetuximab followed by weekly cetuximab, paclitaxel, carboplatin, and concurrent radiation. Recurrence and survival data were compared with previous Brown University studies utilizing the same paclitaxel-based chemoradiation with and without induction chemotherapy. RESULTS: The progression-free survival and overall survival at 3 years for all 37 patients initiating chemoradiation was 54% and 57%, respectively. All surviving patients were followed for at least 3 years and the median follow-up is 4.4 years. Of 14 patients who recurred within 3 years, 7 patients recurred locally only, 5 had a systemic recurrence, and 2 recurred both locally and systemically. CONCLUSIONS: The addition of cetuximab to paclitaxel, carboplatin, and radiation achieves overall survival that is virtually identical to prior Brown University Oncology Group studies of paclitaxel-based chemoradiation without cetuximab. Improvements in locoregional control are needed despite the use of 3 agents to enhance the effects of radiation.

Unusual blasts with basophilic granules in 2 cases of de novo acute myeloid leukemia with inv3(q21q26.2) and monosomy 7 and coexpression of CD2 and CD31.

Acute myeloid leukemia with inv3(q21q26.2)/t(3,3)(q21;q26.2) is a subtype of acute myeloid leukemia associated with significant dysmyelopoiesis and a poor prognosis. In more than a half of the cases, there is also monosomy 7. We present 2 young male patients with de novo acute myeloid leukemia with inversion 3 and monosomy 7 who had significant morphologic and immunophenotypical similarities. Both patients had circulating subsets of blasts with unusual intracytoplasmic basophilic granules and prominent bone marrow dysmegakaryopoiesis. The leukemic myeloid blasts were negative for myeloperoxidase and had aberrant coexpression of CD2 and CD31. Despite their morphologic and immunophenotypical similarities, only 1 of the patients achieved remission and remained free of disease 24 months after bone marrow transplant. The younger patient, who had also increased hemoglobin F and an associated FLT3 D835 variant, had an acute myeloid leukemia refractory to chemotherapy and died 4 months after his diagnosis.

Clinical utility of the combination of lapatinib and letrozole in the management of hormone receptor-positive and HER2-positive advanced breast cancer.

Breast cancers that overexpress human epidermal growth factor receptor-2 (HER2-positive [HER2+]) tend to be biologically aggressive and associated with a poor prognosis, even those that coexpress receptors for estrogen and/or progesterone (hormone receptor-positive [HR+]). Optimal therapy for patients with "double-positive" (HR+/HER2+) breast cancers is still being defined. In this subset of patients, the efficacy of targeted endocrine therapies appears to be diminished by cross-activation or "crosstalk" between estrogen receptor-mediated gene transcription and pathways activated by other growth factor receptors, including HER2. Lapatinib is a tyrosine kinase inhibitor which binds reversibly to the intracellular domains of the epidermal growth factor receptor and HER2, interfering with their ability to initiate signal transduction cascades that promote cancer cell proliferation, survival, and metastasis. In a recently published randomized, placebo-controlled Phase III study in postmenopausal HR+ metastatic breast cancer, the addition of lapatinib to the aromatase inhibitor letrozole significantly improved progression-free survival solely in women who were also HER2+. This article reviews the biology of "double-positive" breast cancers and the rationale underlying combining endocrine and HER2-targeted therapies, including the lapatinib/letrozole combination, for these tumors. Results from the Phase III trial are examined, as well as available data on other combinations of HR and HER2-targeted therapies. Ongoing trials and potential future applications of these combinations in both HR+/HER2+ and other subgroups of breast cancer patients are also discussed.

Multicenter phase II trial of sunitinib in the treatment of nongastrointestinal stromal tumor sarcomas.

PURPOSE To evaluate the potential benefit of continuous daily dosing sunitinib in patients with advanced nongastrointestinal stromal tumor (GIST) sarcomas. PATIENTS AND METHODS A total of 53 patients with advanced non-GIST soft tissue sarcomas received sunitinib 37.5 mg daily. Primary end point was Response Evaluation Criteria in Solid Tumors defined response. Secondary end points were stable disease at 16 and 24 weeks. [(18)F]-fluorodeoxyglucose positron emission tomography was performed on a subset of 24 patients at baseline and after 10 to 14 days of therapy. Results Forty-eight patients were eligible for response. One patient (desmoplastic round cell tumor [DSRCT]) achieved a confirmed partial response (PR) and remained on study for 56 weeks. Ten patients (20%) achieved stable disease for at least 16 weeks. Metabolic PR was seen in 10 (47%) of 21 of patients. Metabolic stable disease was seen in 11 (52%) of 21. There were no unexpected toxicities observed. CONCLUSION Sunitinib demonstrated notable evidence of metabolic response in several patients with non-GIST sarcoma. The relevance of disease control observed in subtypes with an indolent natural history is unknown, however, the durable disease control observed in DSRCT, solitary fibrous tumor, and giant cell tumor of bone suggests that future evaluation of sunitinib in these subtypes may be warranted.

A phase II and pharmacokinetic study of ecteinascidin 743 in patients with gastrointestinal stromal tumors.

PURPOSE: To assess the efficacy, tolerability, and pharmacokinetics of ecteinascidin 743 (ET-743) in patients with advanced gastrointestinal stromal tumors (GISTs). PATIENTS AND METHODS: The study was confined to adult patients with radiographically measurable GISTs. ET-743 was administered as a 24-hour continuous i.v. infusion at a dose of 1.5 mg/m(2) repeated every 3 weeks. Pharmacokinetic blood sampling was performed during the first cycle of therapy. Tumors were restaged after every second cycle of therapy. RESULTS: A total of 20 patients was enrolled in the study, 19 of whom were treated with 47 cycles of ET-743 (median 2, range 1-10). Severe toxicities were limited to reversible grade 3 transaminitis in 10 patients and grade 3 fatigue in one patient. There were no objective responses, and disease stabilization occurred in two patients lasting for periods of 4 and 10 months. The 1-year survival rate was 71.1%. Mean +/- standard deviation values of the maximum plasma concentration and total plasma clearance were 1.1 +/- 0.4 ng/ml and 44 +/- 16 l/h/m(2), respectively, for 19 of the 20 patients. CONCLUSION: This study is the first report of a prospective phase II trial to evaluate a cytotoxic agent in patients with GISTs. This study underscores the primary resistance of GISTS to chemotherapy and stands in stark contrast to the encouraging results recently achieved with STI571. The lack of response may be associated with a therapeutically ineffective exposure to the drug based upon the lower incidence of severe toxicities and greater clearance than described in phase I and II trials of ET-743.