International consensus on the initial diagnostic workup of cancer of unknown primary

BACKGROUND

Although the incidence of Cancer of Unknown Primary (CUP) is estimated to be 1-2 % of all cancers worldwide, no international standards for diagnostic workup are yet established. Such an international guideline would facilitate international comparison, provide adequate incidence and survival rates, and ultimately improve care of patients with CUP.

METHODS

Participants for a four round modified Delphi study were selected via a CUP literature search in PubMed and an international network of cancer researchers. A total of 90 CUP experts were invited, and 34 experts from 15 countries over four continents completed all Delphi survey rounds.

FINDINGS

The Delphi procedure resulted in a multi-layer CUP classification for the diagnostic workup. Initial diagnostic workup should at least consist of history and physical examination, full blood count, analysis of serum markers, a biopsy of the most accessible lesion, a CT scan of chest/abdomen/pelvis, and immunohistochemical testing. Additionally, the expert panel agreed on the need of an ideal diagnostic lead time for CUP patients. There was no full consensus on the place in diagnostic workup of symptom-guided MRI or ultrasound, a PET/CT scan, targeted gene panels, immunohistochemical markers, and whole genome sequencing.

INTERPRETATION

Consensus was reached on the contents of the first diagnostic layer of a multi-layer CUP classification. This is a first step towards full consensus on CUP diagnostics, that should also include supplementary and advanced diagnostics.

Systematic review of the CUP trials characteristics and perspectives for next-generation studies

BACKGROUND

Research on therapeutic strategies for patients with unknown primary cancer (CUP) has been underwhelming. This paper summarized and evaluated the CUP therapeutic research over the previous five years. Based on this evaluation, recommendations for clinical trial designs are made to improve the impact of CUP research on patients.

METHODS

Published and ongoing research were evaluated. PubMed was searched from January 1, 2015, to November 1, 2021. The start date of 2015 was chosen to identify research published after ESMO issued new diagnostic and therapeutic guidelines. The US National Library of Medicine indexed ongoing clinical trials.

FINDINGS

Of the 244 CUP studies indexed in PubMed, 11.9% were prospective studies, and 4.9% were clinical trials. The review protocol deemed 65 publications eligible for full-text review. Eleven studies evaluating therapeutic regimens were retained. The two prospective studies and non-randomized trials showed promising outcomes for site-specific treatments. Randomized clinical trials were less promising; however, the trials had recruitment challenges resulting in biased accrual and the inability to keep pace with advancing diagnostics and therapeutics. Most of the 35 ongoing studies were phase II single-arm trials assessing immune checkpoint inhibitors (ICI) or site-specific therapies among CUP patients with suspected favorable prognoses.

CONCLUSION

Our evaluation suggests two prospective clinical trial designs that addressed recent study design and recruitment challenges. A visionary approach uses a multi-arm, multistage randomized trial to address rapid advancements in diagnosis and therapy. A pragmatic approach utilizes a single-arm trial with historical controls to overcome comparison group and recruitment challenges.

Analysis of the MOSAIC correlative cancer database integrating molecular cancer classification and tumor profiling to identify targeted treatment options for metastatic cancer

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Background: Unless tumor type and genetic alterations can be identified, metastatic cancer patients with unknown or uncertain diagnoses may be limited to empiric chemotherapy. The 92-gene assay (CancerTYPE ID) is a validated gene expression classifier of 50 tumor types and subtypes for patients with cancer of unknown primary (CUP) or ambiguous diagnoses. Multimodal molecular biomarker testing by next-generation sequencing (NGS), tumor mutational burden (TMB), fluorescent in situ hybridization (FISH), microsatellite instability (MSI), and immunohistochemistry (IHC) can identify genetic targets. A database integrating tumor typing with biomarker analysis in metastatic cases was utilized to identify the most prevalent genetic alterations by tumor type. Methods: MOSAIC (Molecular Synergy to Advance Individualized Cancer Care) is an IRB-approved database of cases with CancerTYPE ID testing plus multimodal biomarker testing. The current study determined molecular tumor type followed by molecular profiling by NGS for up to 323 genes, (NeoTYPE profiles, Neogenomics). Results: Tumor type was determined in 1992 of 2151 cases (92.7%), comprised of 27 different tumor types. 72% of cases were comprised of the 7 tumor types shown in the table,which also shows the frequency of the 10 most commonly mutated genes by tumor type. Bolded are genes with actionable genetic mutations for which FDA-approved therapies are not currently indicated in the identified tumor type. Conclusions: Precise targeted treatment for many patients with CUP or ambiguous diagnoses requires accurate diagnosis of the cancer origin combined with multimodal molecular testing to identify actionable genetic alterations in the appropriate cellular context. Future studies will evaluate additional biomarker profiles, including TMB, FISH, MSI, and IHC for cases in the MOSAIC database.[Table: see text]

Development and Validation of a Novel Nomogram for Individualized Prediction of Survival in Cancer of Unknown Primary

PURPOSE

Prognostic uncertainty is a major challenge for cancer of unknown primary (CUP). Current models limit a meaningful patient-provider dialogue. We aimed to establish a nomogram for predicting overall survival (OS) in CUP based on robust clinicopathologic prognostic factors.

EXPERIMENTAL DESIGN

We evaluated 521 patients with CUP at MD Anderson Cancer Center (MDACC; Houston, TX; 2012-2016). Baseline variables were analyzed using Cox regression and nomogram developed using significant predictors. Predictive accuracy and discriminatory performance were assessed by calibration curves, concordance probability estimate (CPE ± SE), and concordance statistic (C-index). The model was subjected to bootstrapping and multi-institutional external validations using two independent CUP cohorts: V1 [MDACC (2017), N = 103] and V2 (BC Cancer, Vancouver, Canada and Sarah Cannon Cancer Center/Tennessee Oncology, Nashville, TN; N = 302).

RESULTS

Baseline characteristics of entire cohort (N = 926) included: median age (63 years), women (51%), Eastern Cooperative Oncology Group performance status (ECOG PS) 0-1 (64%), adenocarcinomas (52%), ≥3 sites of metastases (30%), and median follow-up duration and OS of 40.1 and 14.7 months, respectively. Five independent prognostic factors were identified: gender, ECOG PS, histology, number of metastatic sites, and neutrophil-lymphocyte ratio. The resulting model predicted OS with CPE of 0.69 [SE: ± 0.01; C-index: 0.71 (95% confidence interval: 0.68-0.74)] outperforming Culine/Seve prognostic models (CPE: 0.59 ± 0.01). CPE for external validation cohorts V1 and V2 were 0.67 (± 0.02) and 0.70 (± 0.01), respectively. Calibration curves for 1-year OS showed strong agreement between nomogram prediction and actual observations in all cohorts.

CONCLUSIONS

Our user-friendly CUP nomogram integrating commonly available baseline factors provides robust personalized prognostication which can aid clinical decision making and selection/stratification for clinical trials.

The role of site-specific therapy for cancers of unknown of primary: A meta-analysis

Cancers of unknown primary (CUP) are among the most common causes of death due to cancer, are associated with a poor prognosis and have few therapeutic options available. Molecularly-guided site-specific treatments were explored based on the assumption that CUP are similar in their response to treatment of predicted primary tumours. Given the discordant results between these studies, a meta-analysis using a random-effects model and the inverse variance method was performed. MEDLINE and conference abstracts of American Society of Clinical Oncology (ASCO) and European Society of Medical Oncology (ESMO) meetings were searched from inception until November 2019. A trend towards improved OS was noted with site-specific versus empiric treatment for CUP (HR = 0.73; 95% confidence interval (CI) 0.52-1.02). There was significant heterogeneity across the four studies (I [2] = 79%; p = 0.002) but no significant difference was noted between the treatment effect in the two subgroups (randomised vs. non-randomised; p = 0.07). The test for overall effect for progression free survival, which had only been reported for the two randomised studies, was not statistically significant (HR = 0.93; 95% CI 0.74-1.17), with little heterogeneity between studies (I [2] = 0%; p = 0.77). The results of this meta-analysis highlight the significant heterogeneity between the prospective studies comparing molecularly tailored to empiric therapy for CUP and the need for other randomised studies including only primary tumors with available effective therapies.

Molecular profiling using the 92-gene assay for tumor classification of brain metastases

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Background: Nearly 200,000 patients are diagnosed with brain metastases in the US annually. Advances in targeted therapies make definitive diagnosis of the primary tumor type important but can be challenging in many patients. The 92-gene assay is a validated gene expression classifier of 50 tumor types/subtypes for patients with uncertain diagnoses. Results from a clinical series of brain biopsies and potential impact on treatment were evaluated. Methods: An IRB-approved, de-identified database of clinical and molecular information from biopsies (N = 24,486) submitted for testing with the 92-gene assay (CancerTYPE ID, Biotheranostics, Inc.) as part of routine care were reviewed. Descriptive analysis included patient demographics and molecular diagnoses. Results: Analysis included 464 brain biopsies. A molecular diagnosis was provided in 433 (93.3%) tested ( < 5% assay failure rate) with 24 different tumor types. Six primary tumor types made up the majority (67.4%) with almost one-third of the molecular predictions being Lung (31.2%), followed by Neuroendocrine (NET) (9.9%), Sarcoma (7.9%), Skin (6.4%), Gastroesophageal (6.2%), and Urinary bladder (5.8%). All of these 6 tumor types, for which activity in the CNS has been documented, have immune checkpoint inhibitors or other targeted therapies approved in selected cases by the US Federal Drug Administration (FDA) (Table). Conclusions: Molecular classification of brain metastases can identify distinct tumor types for which there are FDA approved targeted medications. Improving diagnostic precision with the 92-gene assay helps identify a subset of therapy-responsive metastatic brain tumors, thus improving therapy and possibly providing better outcomes and survival. [Table: see text]

Erlotinib plus either pazopanib or placebo in patients with previously treated advanced non-small cell lung cancer: A randomized, placebo-controlled phase 2 trial with correlated serum proteomic signatures

BACKGROUND

This study compared the efficacy and safety of treatment with erlotinib plus pazopanib versus erlotinib plus placebo in patients with previously treated advanced non-small cell lung cancer (NSCLC).

METHODS

Patients with progressive-stage IV NSCLC after either 1 or 2 previous chemotherapy regimens were randomized to receive erlotinib (150 mg by mouth daily) with either pazopanib (600 mg by mouth daily) or placebo. During treatment, patients were evaluated every 8 weeks until disease progression or unacceptable toxicity. After a study amendment, pretreatment serum specimens for the VeriStrat assay were collected. The predictive value of the VeriStrat score (good vs poor) for progression-free survival (PFS) and overall survival (OS) was assessed in the overall population and in each treatment group.

RESULTS

One hundred ninety-two eligible patients were randomized between February 2010 and February 2011. PFS was prolonged with erlotinib plus pazopanib versus erlotinib plus placebo (median, 2.6 vs 1.8 months; hazard ratio, 0.58; P = .001). There was no difference in the OS of the 2 groups. A good VeriStrat score predicted longer PFS and OS in the entire group and predicted longer PFS in the subgroup receiving erlotinib plus pazopanib. The addition of pazopanib increased toxicity, and this was consistent with the known toxicity profile.

CONCLUSIONS

The addition of pazopanib to erlotinib in an unselected group of patients with previously treated NSCLC improved PFS and increased treatment-related toxicity, but it had no influence on OS. The efficacy of both regimens was modest. Patients receiving erlotinib plus pazopanib had longer PFS if they had a good VeriStrat score versus a poor one. Cancer 2018;124:2355-64. © 2018 American Cancer Society.

Amrubicin and carboplatin with pegfilgrastim in patients with extensive stage small cell lung cancer: A phase II trial of the Sarah Cannon Oncology Research Consortium

PURPOSE

First-line treatment for patients with extensive-stage small cell lung cancer (SCLC) includes treatment with platinum-based combination chemotherapy. Amrubicin is a synthetic anthracycline with single-agent activity in relapsed/refractory SCLC. In an attempt to improve treatment efficacy, we evaluated amrubicin/carboplatin as first-line therapy for extensive-stage SCLC.

PATIENTS AND METHODS

In this multicenter phase II trial, patients received amrubicin (30 mg/m² daily on Days 1, 2, and 3) and carboplatin (AUC = 5 on Day 1); cycles were repeated every 21 days for 4 cycles. Pegfilgrastim (6 mg subcutaneously) was administered on Day 4 of all cycles. Overall survival (OS) proportion at 1 year was the primary endpoint. The target 1-year OS rate was 47%, an improvement of 35% from historical results with carboplatin/etoposide.

RESULTS

Eighty patients received study treatment, and 62% completed the planned 4 courses. The overall response rate was 74% (13% complete responses). The 1-year survival rate was 38% (95% CI: 25, 50). The median survival was 10 months. Myelosuppression was severe but manageable.

CONCLUSIONS

The combination of amrubicin/carboplatin was an active first-line treatment for extensive stage SCLC, but showed no indication of increased efficacy compared to standard treatments. Severe myelosuppression was common with this regimen, in spite of prophylactic pegfilgrastim. These results are consistent with those of other trials in showing no role for amrubicin in the first-line treatment of SCLC.

Randomized phase 2 trial of pemetrexed, pemetrexed/bevacizumab, and pemetrexed/carboplatin/bevacizumab in patients with stage IIIB/IV non-small cell lung cancer and an Eastern Cooperative Oncology Group performance status of 2

BACKGROUND

The best treatment for patients with advanced non-small cell lung cancer (NSCLC) and a poor performance status is not well defined. In this phase 2 trial, patients were randomized to receive treatment with either single-agent pemetrexed or 1 of 2 combination regimens.

METHODS

Patients with newly diagnosed, histologically confirmed nonsquamous NSCLC and an Eastern Cooperative Oncology Group (ECOG) performance status of 2 were stratified by age and serum albumin level and were randomized (1:1:1) to 1 of 3 regimens: pemetrexed (arm 1), pemetrexed and bevacizumab (arm 2), or pemetrexed, carboplatin, and bevacizumab (arm 3). The response to treatment was assessed every 2 cycles; responding and stable patients continued treatment until progression or unacceptable toxicity.

RESULTS

One hundred seventy-two patients were randomized, 162 patients began the study treatment, and 146 patients completed 2 cycles and were evaluated for their response. The median progression-free survival (PFS) was 2.8 months in arm 1, 4.0 months in arm 2, and 4.8 months in arm 3. The overall response rates were 15% in arm 1, 31% in arm 2, and 44% in arm 3. The overall survival was similar in the 3 treatment arms. All 3 regimens were relatively well tolerated. Patients receiving bevacizumab had an increased incidence of hypertension, proteinuria, and bleeding episodes, but most events were mild or moderate.

CONCLUSIONS

All 3 regimens were feasible for patients with advanced NSCLC and an ECOG performance status of 2. The addition of bevacizumab to pemetrexed increased the overall response rate. The efficacy of pemetrexed/carboplatin/bevacizumab (median PFS, 4.8 months) approached the prespecified study PFS goal of 5 months. Larger studies will be necessary to define the role of bevacizumab in addition to standard pemetrexed and carboplatin in this population. Cancer 2018;124:1982-91. © 2018 American Cancer Society.

First-Line Carboplatin, Pemetrexed, and Panitumumab in Patients with Advanced Non-Squamous KRAS Wild Type (WT) Non-Small-Cell Lung Cancer (NSCLC)

BACKGROUND

We added panitumumab to standard combination chemotherapy as first-line treatment for patients with advanced KRAS WT non-squamous NSCLC.

METHODS

Patients received panitumumab 9 mg/kg IV, pemetrexed 500 mg/m² IV, and carboplatin AUC = 6 IV every 21 days. After 6 cycles, maintenance therapy with panitumumab and pemetrexed was administered every 21 days until progressive disease or unacceptable toxicity.

RESULTS

29 of 66 patients (44%) had objective responses. The median TTP was 6 months; median overall survival (OS) was 17 months. Panitumumab increased treatment-related toxicity, notably skin rash.

CONCLUSIONS

The addition of panitumumab increased toxicity, and had no discernible impact on efficacy.

Lung Adenocarcinoma with Anaplastic Lymphoma Kinase (ALK) Rearrangement Presenting as Carcinoma of Unknown Primary Site: Recognition and Treatment Implications

Background

Molecular cancer classifier assays are being used with increasing frequency to predict tissue of origin and direct site-specific therapy for patients with carcinoma of unknown primary site (CUP).

Objective

We postulated some CUP patients predicted to have non-small-cell lung cancer (NSCLC) by molecular cancer classifier assay may have anaplastic lymphoma kinase (ALK) rearranged tumors, and benefit from treatment with ALK inhibitors.

Methods

We retrospectively reviewed CUP patients who had the 92-gene molecular cancer classifier assay (CancerTYPE ID; bioTheranostics, Inc.) performed on tumor biopsies to identify patients predicted to have NSCLC. Beginning in 2011, we have tested these patients for ALK rearrangements and epidermal growth factor receptor (EGFR) activating mutations, based on the proven therapeutic value of these targets in NSCLC. We identified CUP patients with predicted NSCLC who were subsequently found to have ALK rearrangements.

Results

NSCLC was predicted by the molecular cancer classifier assay in 37 of 310 CUP patients. Twenty-one of these patients were tested for ALK rearrangements, and four had an EML4-ALK fusion gene detected. The diagnosis of lung cancer was strongly suggested in only one patient prior to molecular testing. One patient received ALK inhibitor treatment and has had prolonged benefit.

Conclusions

We report on patients with lung adenocarcinoma and ALK rearrangements originally diagnosed as CUP who were identified using a molecular cancer classifier assay. Although ALK inhibitors treatment experience is limited, this newly identifiable group of lung cancer patients should be considered for therapy according to guidelines for stage IV ALK-positive NSCLC.

Poorly differentiated neoplasms of unknown primary site: diagnostic usefulness of a molecular cancer classifier assay

PURPOSE

Definition of the lineage of poorly differentiated neoplasms (PDNs) presenting as cancer of unknown primary site (CUP) is important since many of these tumors are treatment-sensitive. Gene expression profiling and a molecular cancer classifier assay (MCCA) may provide a new method of diagnosis when standard pathologic evaluation and immunohistochemical (IHC) staining is unsuccessful.

PATIENTS AND METHODS

Thirty of 751 CUP patients (4%) seen from 2000-2012 had PDNs without a definitive lineage diagnosed by histology or IHC (median 18 stains, range 9-46). Biopsies from these 30 patients had MCCA (92-gene reverse transcriptase-polymerase chain reaction mRNA) performed. Additional IHC, gene sequencing, fluorescent in situ hybridization for specific genetic alterations, and repeat biopsies were performed to support MCCA diagnoses, and clinical features correlated. Seven patients had MCCA performed initially and received site-specific therapy.

RESULTS

Lineage diagnoses were made by MCCA in 25 of 30 (83 %) patients, including ten carcinomas (three germ cell, two neuroendocrine, five others), eight sarcomas [three peritoneal mesotheliomas, one primitive neuroectodermal tumor (PNET), four others], five melanomas, and two lymphomas. Additional IHC and genetic testing [BRAF, i(12)p] supported the MCCA diagnoses in 11 of 16 tumors. All seven patients (two germ cell, two neuroendocrine, two mesothelioma, one lymphoma) responded to site-specific therapy based on the MCCA diagnosis, and remain alive (five progression-free) from 25+ to 72+ months.

CONCLUSION

The MCCA provided a specific lineage diagnosis and tissue of origin in most patients with PDNs unclassifiable by standard pathologic evaluation. Earlier use of MCCA will expedite diagnosis and direct appropriate first-line therapy, which is potentially curative for several of these tumor types.

Rituximab with or without bevacizumab for the treatment of patients with relapsed follicular lymphoma

INTRODUCTION/BACKGROUND

Inhibition of tumor angiogenesis by the interruption of VEGF pathway signaling is of therapeutic value in several solid tumors. Preclinical evidence supports similar importance of the pathway in non-Hodgkin lymphoma. In this randomized phase II trial, we compared the efficacy and toxicity of rituximab with bevacizumab versus single-agent rituximab, in patients with previously-treated follicular lymphoma.

PATIENTS AND METHODS

Patients (n = 60) were randomized (1:1) to receive rituximab (375 mg/m(2) intravenously [I.V.] weekly for 4 weeks) either as a single agent or with bevacizumab (10 mg/kg I.V. on days 3 and 15). Patients with an objective response or stable disease at week 12 received 4 additional doses of rituximab (at months 3, 5, 7, and 9); patients who received rituximab/bevacizumab also received bevacizumab 10 mg/kg I.V. every 2 weeks for 16 doses.

RESULTS

After a median follow-up of 34 months, PFS was improved in patients who received rituximab/bevacizumab compared with patients who received rituximab alone (median 20.7 vs. 10.4 months respectively; HR, 0.40 (95% confidence interval [CI], 0.20-0.80); P = .007). Overall survival was also improved numerically (73% vs. 53% at 4 years), but did not reach statistical significance (HR, 0.40 (95% CI, 0.15-1.05); P = .055). The addition of bevacizumab increased the toxicity of therapy, but both regimens were well tolerated (no grade 4 toxicity).

CONCLUSION

The addition of bevacizumab to rituximab significantly improved PFS. The role of angiogenesis inhibition in the treatment of follicular lymphoma requires further definition in larger clinical trials.

Gene expression profiling in patients with carcinoma of unknown primary site: from translational research to standard of care

Carcinoma of unknown primary site (CUP) is diagnosed in approximately 3 % of patients with advanced cancer, and most patients have traditionally been treated with empiric chemotherapy. As treatments improve and become more specific for individual solid tumor types, therapy with a single empiric combination chemotherapy regimen becomes increasingly inadequate. Gene expression profiling (GEP) is a new diagnostic method that allows prediction of the site of tumor origin based on gene expression patterns retained from the normal tissues of origin. In blinded studies in tumors of known origin, GEP assays correctly identified the site of origin in 85 % of cases and compares favorably with immunohistochemical (IHC) staining. In patients with CUP, GEP is able to predict a site of origin in >95 % of patients versus 35-55 % for IHC staining. Although confirmation of the accuracy of these predictions is difficult, the diagnoses made by IHC staining and GEP are identical in 77 % of cases when IHC staining predicts a single primary site. GEP diagnoses appear to be most useful when IHC staining is inconclusive. Site-specific treatment of CUP patients based on GEP and/or IHC predictions appears to improve overall outcomes; patients predicted to have treatment-sensitive tumor types derived the most benefit. GEP adds to the diagnostic evaluation of patients with CUP and should be included when IHC staining is unable to predict a single site of origin. Site-specific treatment, based on tissue of origin diagnosis, should replace empiric chemotherapy in patients with CUP.

Abstract A166: A Phase I pharmacokinetic/pharmacodynamic (PK/PD) study of the sachet formulation of the oral dual PI3K-mTOR inhibitor BEZ235 given twice daily (BID) in patients (pts) with advanced solid tumors

Background: The PI3 kinase pathway is the most dysregulated pathway in cancers and is an attractive target for antitumor therapy. BEZ235 is a potent, highly specific and selective PI3K inhibitor that also binds to the catalytic site of mTOR, inhibiting mTORC1/2.

Methods: Pts were enrolled in a 3+3 dose escalation design to determine the maximum tolerated dose, toxicities, PK, and PD of BEZ235 when administered BID as an oral sachet formulation. For intrapatient PK comparison, pts received the total dose in a QD schedule for the first 8 days of the initial 28 day cycle. The QD lead-in was later eliminated. PK and PD assessments (PET scans, skin biopsies, and blood-based biomarkers) were collected and disease assessments were conducted every 2 cycles.

Results: 33 pts (median age 62, range 20-86 yrs; 17 male/16 female) received BEZ235 at the doses described below in the table. Two DLTs of gr 3 mucositis occurred early in the treatment cycle at 600 mg BID, so the lead-in QD dosing was eliminated. However, DLTs of fatigue and mucositis limited dosing at 600 mg BID in subsequent pts. The 400 mg BID dose level was re-explored, but dosing was again limited by DLTs and chronic low grade toxicities. Twelve pts were enrolled at an intermediate dose of 300 mg BID with no QD lead-in, and DLT (gr 3 mucositis) was reported in a single patient. Preliminary PK data demonstrate a consistent increase in PK parameters (Cmax and AUC) with dose level compared to QD dosing. PET scan evaluations demonstrate anti-PI3K activity via decreased SUV uptake at various doses, including the lowest dose. 15 pts experienced stable disease as their best response.

Conclusions: The recommended dose of BEZ235 administered twice daily as an oral sachet formulation is 300 mg BID. The toxicity profile for BID dosing is similar to that reported for other PI3K and mTOR inhibitors.

Phase I study of c-Met inhibitor ARQ197 in combination with FOLFOX for the treatment of patients with advanced solid tumors

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Background: C-Met protein is a receptor tyrosine kinase which is overexpressed or mutated in a variety of tumor types, causing cell proliferation, metastasis, and angiogenesis. Tivantinib is an orally bioavailable small molecule which binds to the c-Met protein. This phase I study was designed to determine the maximum tolerated dose (MTD) of tivantinib in combination with standard dose FOLFOX for the treatment of patients with advanced solid tumors. Methods: Patients with advanced solid tumors for which FOLFOX (5-FU IV 400 mg/m2 day 1; 5-FU CIV 2400 mg/m2 day 1; Leucovorin IV 400 mg/m2 day 1; Oxaliplatin IV 85 mg/m2 day 1) would be appropriate chemotherapy received escalating doses of tivantinib BID (days 1-14) in a standard 3 + 3 design. Dose-limiting toxicities (DLTs), non-dose-limiting toxicities (NDLTs), safety, and preliminary efficacy were evaluated. Results: Fourteen patients (50% colorectal) were treated across 3 dose levels: 120 mg (n=3); 240 mg (n=5); 360 mg (n=6). No DLTs were observed until the 3rd dose level (treatment delay ≥3 days, secondary to grade 3 neutropenia). Common related adverse events (% grade 1/2; % grade 3/4) included: diarrhea (36%; 0%), neutropenia (0%; 29%), nausea (14%; 14%), vomiting (14%; 14%), dehydration (14%; 7%), and thrombocytopenia (14%; 0%). To date, 7 patients have been evaluated for response including 4 (57%) with stable disease evident at the 8-week evaluation (CRC, 2 patients; unknown primary favoring CRC, 1 patient; esophageal, 1 patient) and 3 (21%) with disease progression. The 4 patients with stable disease are continuing on treatment; three (CRC and unknown primary) had received prior FOLFOX. Conclusions: The addition of tivantinib to standard therapy FOLFOX appears tolerated up to its recommended phase II monotherapy dose of 360 mg. Preliminary efficacy is encouraging, and a phase II study is proceeding with this regimen for the first line treatment of advanced gastroesophageal patients. Clinical trial information: NCT01611857.

Renal cell carcinoma (RCC) presenting as cancer of unknown primary (CUP): Diagnosis by molecular tumor profiling (MTP)

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Background: CUP is a heterogeneous clinicopathologic syndrome representing many types of occult clinically undetectable primary neoplasms. With the advent of MTP, the tissue of origin in CUP is frequently identified when used in concert with immunohistochemistry (IHC) and clinical features. Histopathology alone is usually not specific, and diagnostic IHC is often limited. Diagnosis of the RCC subset of CUP has important therapeutic potential given the availability of multiple approved biologic therapies, and the use of MTP may facilitate the correct diagnosis. Methods: 488 CUP patients (pts) seen between 2008 – 2012 had MTP (RT-PCR 92-gene assay, CancerTYPE ID, bioTheranostics, Inc.) of their archived tumor specimens. The clinicopathologic features were reviewed and, where feasible, subsequent additional IHC stains were obtained to support the MTP diagnosis. The response and survival to first-line RCC site-specific therapy were evaluated. Results: RCC was the MTP diagnosis in 22 pts (4.5%), including papillary in 8, clear cell in 7, and unknown subtype in 7. Histology included poorly differentiated carcinoma in 15 and adenocarcinoma in 7 (4 with papillary features, 1 with clear cell features). None had evidence of a primary renal lesion detectable by abdominal computed tomography, and the sites of metastasis most often included retroperitoneal nodes (63%), mediastinal nodes (31%), lung (22%), and bone (18%). Diagnostic RCC IHC stains were performed initially in only 3 tumors (14%), but RCC IHC stains (RCC, PAX 8, others) performed later supported the MTP diagnosis in 7 of 9 tumors where remaining tissue was available. 16 pts received first-line RCC targeted therapies (objective response rate was 18%, median survival of 13.4). Conclusions: RCC is a subset of CUP which can be diagnosed by MTP. RCC is usually not suspected in the absence of clear cell features, and occult RCC appears to commonly be the papillary subtype. RCC IHC may be diagnostic in some CUP tumors, but may be omitted in the initial pathologic evaluation. CUP-RCC pts are important to identify as they may benefit from standard RCC targeted therapies, and respond poorly to empiric chemotherapy.

Multivariate analysis of prognostic factors in cancer of unknown primary (CUP) patients treated with site-specific therapy based on the 92-gene cancer classifier

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Background: Results from a single arm prospective study demonstrated overall survival of 12.5m in 194 patients that received first-line therapy directed by tumor classification using the 92-gene assay (JCO, 31:217-23). When the molecular assay predicted tumor types that were clinically more responsive, median survival was significantly improved when compared with predictions of more resistant tumors (13.4 v 7.6 m; p= 0.04).In this analysis, the survival benefit of assay-directed therapy was further evaluated after adjusting for pre-treatment prognostic factors. Methods: Cox proportional hazards regression was used to examine survival benefit of responsive tumor types (n=115) vs resistant tumor types (n=79) predicted by the molecular assay, after controlling for traditional prognostic factors. Results: Univariate Cox regression analysis (n=194) showed that ECOG status, responsive vs resistant tumor type, and assay probability were each significant prognostic factors. In multivariate analyses, the prognostic value of only ECOG status and the assay prediction of responsive vs resistant tumor type were maintained. Conclusions: These data demonstrate that the 92-gene assay results remained a significant independent variable affecting survival outcome in these patients after adjustment for prognostic heterogeneity, and provide further support of assay accuracy in molecular classification of CUP. Clinical trial information: NCT00737243. [Table: see text]

Double-blind randomized phase II trial of carboplatin and pemetrexed with or without OGX-427 in patients with previously untreated stage IV non-squamous non-small-cell lung cancer (NSCLC): The Spruce Clinical Trial

TPS8120

Background: OGXE427 is an antisense oligonucleotide (ASO) designed to bind to Hsp27 (heat shock protein 27) mRNA, resulting in the inhibition of production of Hsp27 protein. Hsp27 is over-expressed in many cancers including lung, prostate, breast, and bladder. Increased expression has been associated with inhibition of chemotherapy-induced apoptosis, increased tumor cytoprotection, and the development of treatment resistance. OGX-427 is an inhibitor of Hsp27 that effectively targets and down-regulates Hsp27 mRNA and has been shown to increase apoptosis, inhibit tumor growth, and sensitize cells to various chemotherapy regimens in a variety of malignancies. Based on this preclinical data, addition of an Hsp27 inhibitor to standard chemotherapy may improve the efficacy of treatment. In this randomized phase II study, OGX-427 will be added to a standard carboplatin/pemetrexed regimen, with the goal of improving progression-free survival when compared to carboplatin and pemetrexed alone in the first-line treatment of non-squamous NSCLC patients. Methods: A total of 155 patients will be randomized in a 1:1 ratio. Randomization will be stratified by histology (adenocarcinoma vs. large cell carcinoma) and smoking status (smoker vs. non-smoker). Treatment will include a loading dose period with OGX-427 600 mg or placebo. On day one of each 21 day cycle, patients will receive OGX-427 1000 mg or placebo, pemetrexed 500 mg/m2, and carboplatin AUC 6, all administered IV. On days 8 and 15, OGX-427 or placebo will also be administered. Key eligibility criteria include; untreated recurrent or stage IV predominantly non- squamous NSCLC, measureable disease by RECIST v 1.1, ECOG PS 0 or 1, adequate organ function, and no known CNS disease. Serum Hsp27 levels will be assessed at screening, baseline and during treatment. In addition, archival tissues will be collected and assessed for PTEN (protein expression by IHC) and a panel of gene mutations for correlative analyses.

Molecular tumor profiling (MTP) of poorly differentiated neoplasms (PDN) of unknown primary site

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Background: The inability to definitively determine the lineage of neoplasms is less common with modern immunohistochemistry (IHC) and genetic profiling. Nonetheless some PDN defy lineage classification by extensive standard pathologic evaluation. The advent of MTP may provide a new method of improving the diagnosis of these challenging cancers. Methods: A total of 30 of 751 (4%) patients (pts) seen from 2000 – 2012 with cancer of unknown primary (CUP) had PDN without a definitive lineage determined by IHC (median 18 IHC stains, range 9 – 51). From 2008 – 2012 the 30 biopsies had MTP (RT-PCR mRNA CancerTYPE ID, bioTheranostics, Inc.). Additional IHC, genetic sequencing, fluorescent in situ hybridization for specific chromosomal changes and repeat biopsies were performed when feasible to support the MTP diagnosis, and clinical features correlated. Results: MTP lineage diagnoses were made in 25 of 30 (83%), including 10 carcinomas (3 germ cell, 2 neuroendocrine, 5 others), 5 melanomas, 8 sarcomas (3 peritoneal mesothelioma, 1 PNET) and 2 hematopoietic neoplasms (1 lymphoma, 1 chloroma). Additional IHC, genetic testing [BRAF, i(12)p] or repeat biopsies confirmed the MTP diagnoses in 11 of 15 tumors, and the clinical features were consistent with the MTP diagnoses in the majority of patients. Conclusions: This MTP assay can frequently provide a diagnosis for CUP pts and PDN without a definitive lineage defined by extensive IHC. The earlier application of MTP will likely provide an expedited diagnosis, and for some neoplasms is the only test capable of defining lineage and a more specific diagnosis. Appropriate therapy, particularly for pts with germ cell tumors, melanoma, and lymphoma depends on a specific tissue of origin diagnosis.

KRAS subset analysis from randomized phase II trials of erlotinib versus erlotinib plus sorafenib or pazopanib in refractory non-small cell lung cancer (NSCLC)

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Background: KRAS mutations are among the most common genetic alterations in NSCLC; however no targeted therapies have been approved to benefit this lung cancer subset. Between 2/2008 and 2/2011 our center conducted two consecutive multicenter randomized phase II trials in patients (pts) with refractory NSCLC comparing erlotinib/placebo versus erlotinib + either sorafenib or pazopanib, both oral multikinase inhibitors (Spigel et al, JCO 2011; Chicago MSTO 2012). Progression-free survival (PFS) was improved with the multikinase regimens in the EGFR wild-type (WT) subsets, but not in the overall populations. An unplanned analysis of the combined KRAS subset data is the subject of this report. Methods: Eligibility criteria for both trials included: stage IIIB/IV NSCLC; 1 to 2 prior regimens; ECOG performance status 0–2; measurable disease. PFS was the primary endpoint of each trial. Treatment groups included: erlotinib/placebo (N=121), erlotinib/sorafenib (N=112), and erlotinib/pazopanib (N=127). 168 pts (47%) in these three groups had sufficient tumor specimens for KRAS analysis. Results: The PFS and OS results based on KRAS results are shown in the Table below. Conclusions: Patients in whom the KRAS mutation status was known achieved a significantly longer PFS with erlotinib and a multikinase inhibitor than with erlotinib alone. Although this unplanned combined analysis has several limitations, the greater PFS and OS benefits in pts with KRAS mutations warrant further study. Clinical trial information: NCT00600015; NCT01027598. [Table: see text]

First-line carboplatin, pemetrexed, and panitumumab in patients with advanced nonsquamous KRAS wild type (WT) non-small cell lung cancer (NSCLC)

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Background: KRAS WT colorectal cancer (CRC) is responsive to the EGFR inhibitors panitumumab (P) and cetuximab. Phase III data suggest a small, but statistically significant overall survival (OS) advantage with cetuximab + chemotherapy in KRAS unselected NSCLC (Pirker, Lancet 2009); and phase I data suggest P alone has activity in non-CRC tumors including NSCLC (Weiner, Clin Ca Res. 2008). This single-arm phase II trial examined the safety and efficacy of P in combination with carboplatin (C) and pemetrexed (Pem) in patients (pts) with advanced non-squamous KRAS WT NSCLC. The addition of P was hypothesized to improve the median time-to-progression (TTP) from 3.6 months (mos) (historical) to 5.4 mos (1-sided α .10, 80% power). Methods: Pts with previously untreated, unresectable stage IIIB/IV non squamous KRAS WT NSCLC received P 9 mg/kg, Pem 500 mg/m2, and C AUC=6 IV day 1 every 21 days for 6 cycles, followed by P and Pem maintenance every 21 days until progressive disease or unacceptable toxicity. Responses were evaluated every 2 cycles per RECIST 1.1. KRAS mutation testing was performed centrally (DxS kit). Tissue was also collected for EGFR FISH testing. Results: 60 pts were enrolled; median age, 65 years; 58% female, ECOG PS 0-1 (98%), and prior adjuvant chemotherapy (10%). Median number of cycles was 5 (range 1-22). At a median follow-up of 8.7 mos, the median TTP was 6.2 mos (95% CI: 3.7, 9.5), PFS 6.2 mos (95% CI 3.0, 9.0), 1 year OS 65.5% (95% CI 44.8%, 80%). 23 pts (38%) had partial responses (PR); the disease control rate (PR + proportion with stable disease) was 68%. Treatment-related toxicity (TRT) included (all grades) nausea (38%), fatigue (30%), rash (30%), and mucositis (23%). Severe (grade 3/4) TRT in > 2 pts included: thrombocytopenia (11%), neutropenia (7%), and dehydration (5%). There were no treatment-related deaths. EGFR mutation and FISH analyses will be presented. Conclusions: The addition of panitumumab to carboplatin and pemetrexed in the first-line treatment of advanced KRAS WT NSCLC was safe and well-tolerated; the median TTP of 6.2 mos met the primary endpoint. Definitive assessment of the value of panitumumab in this setting requires a randomized trial. Clinical trial information: NCT01042288.

Confirmation of non-small cell lung cancer (NSCLC) diagnosis using ALK testing and genetic profiling in patients presenting with carcinoma of unknown primary site (CUP)

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Background: Emerging data suggest real-time reverse transcriptase-polymerase chain reaction (RT-PCR) tumor profiling can predict the primary site in CUP. We report on CUP patients (pts) predicted to have NSCLC by RT-PCR, in whom detection of ALK rearrangements provided further diagnostic support. Methods: 4 pts were diagnosed with CUP based on standard clinical, radiographic, pathologic evaluation with immunohistochemistry (IHC), and bronchoscopy/endoscopy where indicated. All pts had a RT-PCR assay (CancerTYPE ID, bioTheranostics, Inc.) performed on tumor specimens for the purpose of predicting a primary site. Tissue was also tested for ALK by FISH using a break-apart probe. Results: Pt characteristics are shown (Table). RT-PCR results prompted ALK testing in Pts 2 and 3. ALK testing and RT-PCR testing were performed concurrently in Pts 1 and 4. Each specimen was diagnosed as lung adenocarcinoma (AC) by RT-PCR gene profiling, and also tested positive for an EML4-ALKrearrangement. All pts are being followed for clinical outcome. Conclusions: Gene expression profiling in CUP diagnosed lung AC in 4 pts who also had ALK rearrangements supporting the diagnosis. Identifying ALK-positive NSCLC among pts who present with CUP improves the site-specific treatment options. [Table: see text]

Molecular profiling diagnosis in unknown primary cancer: accuracy and ability to complement standard pathology

BACKGROUND

Molecular tumor profiling (MTP) is a potentially powerful diagnostic tool for identifying the tissue of origin in patients with cancer of unknown primary (CUP). However, validation of the accuracy and clinical value of MTP has been difficult because the anatomic primary site in most patients is never identified.

METHODS

From March 2008 through January 2010, clinicopathologic data from 171 CUP patients who had MTP (CancerTYPE ID; bioTheranostics, Inc, San Diego, CA) performed on archived material were evaluated. The accuracy of MTP diagnoses was evaluated by comparison with (1) latent primary tumor sites found months/years later; (2) initial single diagnoses by immunohistochemistry (IHC); and (3) additional directed IHC and/or clinicopathologic findings evaluated after MTP diagnoses.

RESULTS

A single MTP diagnosis was made in 144 of 149 patients with adequate tumor specimens. Eighteen of 24 patients with latent primaries discovered months to years later had correct diagnoses by MTP (75%), and these diagnoses compared favorably with IHC. Single IHC diagnoses matched MTP diagnoses in 40 of 52 patients (77%). IHC predictions of 2 or more possible primaries compared poorly with MTP diagnoses. However, additional targeted IHC and clinical/histologic evaluation supported the MTP diagnosis in 26 of 35 patients (74%). Clinical features were usually consistent with MTP diagnoses (70%).

CONCLUSIONS

The diagnostic accuracy of this MTP assay was supported by a high level of agreement with identified latent primaries (75%), single IHC diagnoses (77%), and additional directed IHC and/or clinical/histologic findings (74%) prompted by the MTP diagnoses. MTP complements standard pathologic evaluation in determining the tissue of origin in patients with CUP, particularly when IHC is inconclusive.

Sorafenib and everolimus in advanced clear cell renal carcinoma: a phase I/II trial of the SCRI Oncology Research Consortium

PURPOSE

To evaluate the feasibility and efficacy of sorafenib and everolimus in renal cell carcinoma (RCC).

METHODS

Patients with advanced RCC and ≤ 1 previous targeted therapy were treated.

RESULTS

Maximum tolerated doses were sorafenib 200 mg PO BID, everolimus 35 mg PO once weekly. Dose-limiting toxicity was hand-foot syndrome. The response rate was 13%; median PFS was 5.45 months (95% CI: 3.8-7.6). Skin toxicity, fatigue, hypertension, proteinuria, and mucositis (usually Grade 2) were common.

CONCLUSIONS

Fifty percent doses of sorafenib and everolimus were required when these drugs were combined. No increase in efficacy was suggested; toxicity was modestly increased.

Molecular Gene Expression Profiling to Predict the Tissue of Origin and Direct Site-Specific Therapy in Patients With Carcinoma of Unknown Primary Site: A Prospective Trial of the Sarah Cannon Research Institute

Purpose

Molecular tumor profiling is a promising diagnostic technique to determine the tissue of origin in patients with carcinoma of unknown primary site (CUP). However, the clinical value of these molecular predictions is unknown. We used tumor profiling results to direct site-specific therapy for patients with CUP.

Patients and Methods

Tumor biopsy specimens from previously untreated patients with CUP were tested with a 92-gene reverse transcriptase polymerase chain reaction cancer classification assay. When a tissue of origin was predicted, patients who were treatment candidates received standard site-specific first-line therapy.

Results

Of 289 patients enrolled, 252 had successful assays performed, and 247 (98%) had a tissue of origin predicted. Sites most commonly predicted were biliary tract (18%), urothelium (11%), colorectal (10%), and non–small-cell lung (7%). Two hundred twenty-three patients were treatment candidates, and 194 patients received assay-directed site-specific treatment. In these 194 patients, the median survival time was 12.5 months (95% CI, 9.1 to 15.4 months). When the assay predicted tumor types that were clinically more responsive, the median survival was significantly improved when compared with predictions of more resistant tumors (13.4 v 7.6 months, respectively; P = .04).

Conclusion

In this large prospective trial, molecular tumor profiling predicted a tissue of origin in most patients with CUP. The median survival time of 12.5 months for patients who received assay-directed site-specific therapy compares favorably with previous results using empiric CUP regimens. Patients with CUP predicted to have more responsive tumor types had longer survival compared with patients with less responsive tumor types. Molecular tumor profiling contributes to the management of patients with CUP and should be a part of their standard evaluation.

Cancer of unknown primary site: improved patient management with molecular and immunohistochemical diagnosis

Cancer of unknown primary site (CUP) is a common heterogeneous clinicopathologic syndrome, but investigations and publications regarding these patients are rare. For the last 20 years, empiric "broad-spectrum" chemotherapy has been the standard therapy for the majority of these patients. More recently, improved immunocytochemistry and advent of gene-expression profiling have provided the diagnostic tools necessary to accurately define the tissue of origin in most patients. Molecular profiling assays complement standard pathologic diagnosis, and a recently reported large prospective study demonstrated an improvement in outcome for patients treated with site-specific therapy directed by the molecular assay diagnoses compared with empiric chemotherapy. Survival in molecularly diagnosed patients was as expected for those particular tumor types. The evaluation of patients has become more standardized. The empiric-chemotherapy era is ending and customized therapies based on accurate tissue of origin diagnoses have arrived. Eventually the recognition of the molecular aberrations responsible for the growth and metastasis of solid tumors, regardless of the tissue of origin, will lead to more precise and effective therapy for patients with advanced cancers.

Phase II trial of ixabepilone and carboplatin with or without bevacizumab in patients with previously untreated advanced non-small-cell lung cancer

BACKGROUND

Epothilones, a new class of cytotoxic agents, have demonstrated activity in non-small-cell lung cancer (NSCLC). This phase II study examined ixabepilone/carboplatin (cohort A) and ixabepilone/carboplatin/bevacizumab (cohort B) as first-line therapy for patients with advanced NSCLC.

METHOD

Patients were enrolled to either cohort A or B at physician discretion and when eligibility met. Eligible patients had newly diagnosed stage III/IV NSCLC, ECOG PS 0-1, adequate organ function, no active CNS metastases, and, in cohort B, bevacizumab treatment criteria. Both cohorts received ixabepilone 30 mg/m2 and carboplatin AUC=6 IV day 1 every 3-weeks for a maximum of 6 cycles. Patients assigned to cohort B also received bevacizumab 15 mg/kg IV day 1 of each cycle, and could continue single-agent bevacizumab for 6 additional cycles.

RESULTS

Eighty-two patients (median age, 63 years; majority stage IV and former smokers) were enrolled from 11/08 to 10/09 (A-42, B-40) and received medians of 4 and 6 cycles, respectively. The ORRs were 29% and 50%. After median follow up of 17.5 months (A) and 15.7 months (B), median progression free survivals were A-5.3 months (95% CI 2.8-8.6) and B-6.7 months (95% CI 5.1-8.4), with median overall survivals of 9.3 months (95% CI 6.4-16.6) 13.2 months (95% CI 8.9-upper limit not reached), respectively. Grade 3/4 toxicity included: anemia (A-10%, B-27%), neutropenia (A-31%, B-48%), thrombocytopenia (A-19%, B-20%), fatigue (A-10%, B-23%), infection (A-5%, B-20%), and hypersensitivity reaction (A-2%, B-5%). There was one treatment-related death, due to hemoptysis in a cohort B patient with squamous histology.

CONCLUSIONS

Ixabepilone can be safely combined with carboplatin in newly diagnosed patients with advanced NSCLC. The benefits of treatment appear consistent with those achieved with other modern platinum-doublet regimens. The addition of bevacizumab increases toxicities, however, these are largely expected and reversible. The high ORR and OS observed in the bevacizumab-cohort are encouraging, but would require validation in a larger randomized trial of cohort A versus B.

Cancer of unknown primary site: evolving understanding and management of patients

Cancer of unknown primary site is a common clinicopathologic syndrome representing a very heterogeneous group of patients with metastatic cancers and clinically undetectable primary tumor sites. The standard treatment for these patients for the last 15 years has been empiric "broad-spectrum" chemotherapy. In recent years, improved immunocytochemistry and the emergence of gene expression profiling have provided the diagnostic tools necessary to accurately define the tissue of origin in the majority of patients. Recent data have confirmed the ability of molecular profiling assays to complement standard pathologic diagnosis, and a large prospective study has documented a survival improvement for patients treated with site-specific therapy directed by the molecular assay diagnoses of their tissues of origin compared to empiric chemotherapy. The clinicopathologic evaluation of patients is now more standardized. The era of empiric chemotherapy administered to all patients is coming to an end, and customized therapies are favored. The management of patients has evolved with the ability to confidently define the tissue of origin. Further delineation of the molecular aberrations in advanced solid tumors, regardless of the primary tumor site, signals a more precise and perhaps more effective therapy for each patient.

Cancer of unknown primary: progress in the search for improved and rapid diagnosis leading toward superior patient outcomes

This paper explores the enigma of cancer of unknown primary (CUP) in relation to rapidly improving molecular diagnostic approaches. It is based on the first global collaboration meeting on improving research and clinical outcomes in CUP organized by the CUP Foundation. We review the difficulties of classifying this widely heterogeneous disease and the available diagnostic and pathological evaluative techniques, focusing on molecular profiling. Retrospective studies in CUP patients are shown to provide indirect validation of the accuracy of several platforms of gene expression profiling assays that may identify CUP subsets that respond favorably to active chemotherapy regimens. This review concludes that the recent major improvements in pathologic and molecular diagnostics, coupled with new improved therapies for several specific advanced solid tumors, need to be harmonized with more evidence from clinical-translational trials. All patients with CUP could thus be appropriately managed without the constant uncertainty that has previously severely hampered patient care and optimal outcomes. The longer-term objective is to understand the biology of highly metastatic disease, leading to the development of future global therapeutic programs. Current clinical studies, such as CUP-ONE, will address some of these issues.

A drug interaction study evaluating the pharmacokinetics and toxicity of sorafenib in combination with capecitabine

PURPOSE

To address tolerability and a possible pharmacologic interaction of capecitabine with sorafenib.

METHODS

Patients with advanced solid tumors (ECOG PS 0-1) were included. Cohort A received capecitabine 750 mg/m(2) BID and Cohort B received capecitabine 1,000 mg/m(2) BID, both for 14 days of a 21-day cycle. Steady-state PK was obtained for capecitabine alone, sorafenib alone, and in combination. Cohort C explored an alternate schedule of 7-day on/7-day off flat dose capecitabine 1,000 mg BID with continuous dosing of sorafenib 400 mg BID.

RESULTS

A total of 32 patients were enrolled between February 08 and April 09. Hand-foot skin reaction (HFSR) was the primary toxicity with 16 (50%) of the 32 patients experiencing grade 3 events (75% occurring during cycles 1-2). Grade 3 HFSR defined the maximum tolerated dose (MTD) of Cohort C at 1,000 mg BID flat dose of capecitabine. Other grade 3/4 toxicities were rare (diarrhea 6%, mucositis 3%, and fatigue 3%). Capecitabine did not change the C (max) or AUC((0-12)) of sorafenib. Co-administration of sorafenib with capecitabine 750 mg/m(2) (n = 6 patients) increased capecitabine AUC((0-12)) 15% and produced no change in the 5FU AUC((0-12)). At the capecitabine 1,000 mg/m(2) dose level (n = 12 pts), there was a 16% increase in capecitabine AUC((0-12)) and an 8% increase in 5FU AUC((0-12)). However, these trends were not statistically significant.

CONCLUSIONS

Co-administration of sorafenib resulted in a mild increase in capecitabine AUC, although not statistically significant. Capecitabine did not affect the exposure of sorafenib. The rate of grade 3 HFSR is concerning and limits the feasibility of prolonged dosing of sorafenib with capecitabine 1,000 mg/m(2) on the 21-day schedule.