A phase II trial of pembrolizumab and cabozantinib in patients (pts) with recurrent metastatic head and neck squamous cell carcinoma (RMHNSCC)

6008

Background: Pembrolizumab (pembro) is an immune checkpoint inhibitor (ICI) approved for treating pts with recurrent/metastatic (RM) HNSCC. Cabozantinib (cabo) is a multiple receptor tyrosine kinase inhibitor (TKI) targeting MET and VEGFR2 shown to reduce tumor growth, metastasis, and angiogenesis and has immuno-modulatory properties. Methods: This is a phase II, open label multi-center, single arm trial evaluating the tolerability and clinical benefit of pembro administered at 200 mg every 3 weeks and cabo 40 mg daily for pts with RM HNSCC who have not received prior ICI. It had a lead-in safety cohort allowing reduction of cabo dose to 20mg daily. Eligible pts had RM HNSCC, deemed incurable, with a tumor PD-L1 CPS > 1, RECIST 1.1 measurable disease, a life expectancy of > 3 months, an Eastern Cooperative Group (ECOG) Performance Status (PS) of 0-1. Enrollment was initiated in March of 2019. We estimated that the ORR will improve to 35% with pembro+ cabo (from a historic of 18%) with a significance level of 0.05 and 80% power. Results: A total of 47 pts were screened, 13 screen failures [cavitation on scan (4), inability to swallow pills (2), other exclusions (7)]; 34 pts were enrolled, 32 were dosed and 31 evaluable (at least one follow-up scan). Pts had cancers of the oropharynx (21, 65%), nasopharynx (6, 19%), larynx/hypopharynx (4, 13%) and oral cavity (1,3%). 32 patients received cabo at 40 mg daily; 13 patients (41%) were dose reduced to 20mg daily [mucositis, increased liver function (LFT) tests, diarrhea]; males (n=29, 90%), median age 63 years (range 53-67); presence of distant metastases (34, 100%); prior radiation (29, 90%), chemotherapy (14, 43%); ECOG PS =0 (16, 50%), 1 (16,50%); HPV/p16 positive (17, 53%), negative (5, 16%), not applicable (10, 29%); the most frequent adverse event (AE) (all grades) was fatigue (16,50.0%), grade 3 or 4 treatment-related AE were increased LFTs, hyponatremia (3, 9.3% each). With a median follow up of 12.7 months (mos) (range 6.9- 20.5 mos), a RECIST 1.1 overall response rate ORR= 45.2% (CR=0; PR=14, 45.2%; SD =14, 45.2%; PD=3.0, 10%) with an overall clinical benefit of 90.4% were observed; The 1-yr OS was 67.7% (95% CI, 42.9%-83.6%; median 22.3 mos) and 1-yr PFS was 51.8% (95% CI, 28.8%-70.7%; median 14.6 mos). Conclusions: This phase II trial of pembro + cabo met its primary endpoint of ORR. The regimen is well-tolerated with very encouraging clinical activity in RM HNSCC and warrants further exploration in this disease. The study was supported by a grant from Exelixis to NFS. Clinical trial information: NCT03468218.

Oral human papillomavirus prevalence, persistence, and risk-factors in HIV-positive and HIV-negative adults

Background

HIV has been shown to increase the likelihood of oral HPV infection. In this study, we evaluated the risk of oral HPV in HIV infected patients compared with HIV-negative controls.

Methods

101 healthy adult volunteers (HIV-) and 245 adults living with HIV infection (HIV+) were recruited from 5 academic medical centers. Questionnaires and saliva samples were obtained every 3–8 months over a period of 2 years (2015–2017). DNA was isolated from the saliva samples and tested for 18 high- and low-risk genotypes.

Results

Oral HPV was detected in 23% of HIV + vs. 10% of HIV- participants (p < 0.0001). Men had a higher oral HPV prevalence than women (27% vs. 15% HIV+, p = 0.03, 16% vs. 5% HIV-, p = 0.01). Risk factors among HIV + participants included more lifetime deep kissing and oral sex partners, and history of AIDS. Persistent oral HPV was detected in 23% of HIV + vs. 5% of HIV- participants (p < 0.001). Among 8 HIV + participants with CD4 counts <200 cell/μL none had cleared their HPV infection during the study.

Conclusions

Risk of oral HPV infection and persistence was significantly higher in HIV + adults with a history of poorly controlled HIV, which may put them at increased risk of HPV-associated cancer.

Update on safety and efficacy of a phase 1/2 of SNS-301 added to pembrolizumab in patients with advanced squamous cell carcinoma of the head and neck (SCCHN)

6029

Background: The absence of infiltrating antigen-specific CD8+ T-cells at baseline is associated with low response rates to PD-1 blockade. SCCHN tumors often exclude effector T cells, and 2nd line response rates are low (13-18%). Highly immunogenic, antigen specific antitumor vaccines may expand intratumoral CD8+ T cells, potentially increasing durable response rates to PD-1 blockade. SNS-301 is a first-in-class, bacteriophage-based immune activating agent targeting human aspartate β-hydroxylase (ASPH), a tumor associated antigen overexpressed in multiple tumor types. SNS-301 is a self-adjuvanted vaccine consisting of λ-bacteriophage engineered to express an immunogenic fragment of ASPH fused to the phage gpD coat protein. The study objectives are to evaluate safety, immunogenicity and preliminary efficacy of SNS-301 added to pembrolizumab in patients (pts) not achieving tumor reductions on PD-1 blockade alone. Methods: Intradermal SNS-301 was combined with pembrolizumab in pts with locally advanced unresectable (LA) or metastatic/recurrent (met) SCCHN with a best response of stable disease (SD) or unconfirmed progressive disease (uPD) on ongoing PD-1 blockade > 12 weeks. Pts provided pre and on-treatment biopsies to characterize the tumor microenvironment using Nanostring and multiplex immunohistochemistry (mIHC). Blood samples were collected to evaluate B and T cell responses using ELISA/ELISPOT assays. Results: As of February 4, 2021, 13 pts were enrolled. Median duration of PD-1 blockade was 48 weeks (range 14-114) at study entry. There were no DLTs & mostly Grade 1-2 unrelated adverse events. Only two related Grade 3 events were reported: rash & dehydration (also a serious adverse event). Ten pts were evaluable for efficacy: 1 pt with PD-L1 negative (neg) disease & SD on pembrolizumab monotherapy achieved a partial response (PR; -52% at 8 months), 4 pts achieved SD & 5 pts had progressive disease. Two of the pts with SD had long-lasting duration (8 & 10 months) of which the latter had PD-L1 neg disease. One pt with uPD at enrollment achieved SD for 4 months. Analyses of pre- & on-treatment biopsies from the PR pt demonstrated an increase in infiltrating CD8+ T cells, PD-L1 expression & PD-1/PD-L1 proximity measures. Nanostring analysis demonstrated increased gene expression signatures for immune cells in the PR pt that was concordant with the mIHC & clinical outcome. Conclusions: The combination of SNS-301 and pembrolizumab was well-tolerated and resulted in encouraging clinical efficacy in pts not expected to respond to PD-1 blockade alone. Translational data suggest cellular response to SNS-301 and transformation of a poorly inflamed tumor to an immunologically active tumor in a responding pt (PR). Based on these data, an additional cohort will start enrolling PD-1 blockade naïve pts with LA/met SCHNN in the front-line setting. Clinical trial information: NCT04034225.

Quality characteristics of yogurts fermented with short-chain fatty acid-producing probiotics and their effects on mucin production and probiotic adhesion onto human colon epithelial cells

Probiotics can ferment nondigestible carbohydrates and produce short-chain fatty acids (SCFA; acetate, propionate, and butyrate) in the human colon. In this study, the levels of SCFA were determined in the following yogurts fermented with different combinations of probiotics: (1) cocultures of Streptococcus thermophilus and Lactobacillus bulgaricus (control, C); (2) S. thermophilus, L. bulgaricus, and Bifidobacterium bifidum (C-Bb); (3) S. thermophilus, L. bulgaricus, and Lactobacillus acidophilus (C-La); and (4) S. thermophilus, L. bulgaricus, and Lactobacillus gasseri (C-Lg). Results showed that the acetate levels were significantly higher in C-Bb, C-La, and C-Lg yogurts than in C yogurt. Fermentation and physicochemical characteristics of all yogurts were identical. Treatment of mucus-secreting colon epithelial cells (HT29-MTX) with C-Bb, C-La, and C-Lg yogurt supernatants resulted in an increase in the expression of MUC2 and CDX2 and the production of mucin proteins. The adhesion of probiotics onto HT29-MTX cells increased following treatment with C-Bb, C-La, and C-Lg yogurt supernatants. Our data suggest that a yogurt diet rich in acetate improves the protective function of the intestinal epithelium.

Signatures of somatic mutations and gene expression from p16INK4A positive head and neck squamous cell carcinomas (HNSCC)

Human papilloma virus (HPV) causes a subset of head and neck squamous cell carcinomas (HNSCC) of the oropharynx. We combined targeted DNA- and genome-wide RNA-sequencing to identify genetic variants and gene expression signatures respectively from patients with HNSCC including oropharyngeal squamous cell carcinomas (OPSCC). DNA and RNA were purified from 35- formalin fixed and paraffin embedded (FFPE) HNSCC tumor samples. Immuno-histochemical evaluation of tumors was performed to determine the expression levels of p16^INK4A and classified tumor samples either p16+ or p16-. Using ClearSeq Comprehensive Cancer panel, we examined the distribution of somatic mutations. Somatic single-nucleotide variants (SNV) were called using GATK-Mutect2 (“tumor-only” mode) approach. Using RNA-seq, we identified a catalog of 1,044 and 8 genes as significantly expressed between p16+ and p16-, respectively at FDR 0.05 (5%) and 0.1 (10%). The clinicopathological characteristics of the patients including anatomical site, smoking and survival were analyzed when comparing p16+ and p16- tumors. The majority of tumors (65%) were p16+. Population sequence variant databases, including gnomAD, ExAC, COSMIC and dbSNP, were used to identify the mutational landscape of somatic sequence variants within sequenced genes. Hierarchical clustering of The Cancer Genome Atlas (TCGA) samples based on HPV-status was observed using differentially expressed genes. Using RNA-seq in parallel with targeted DNA-seq, we identified mutational and gene expression signatures characteristic of p16+ and p16- HNSCC. Our gene signatures are consistent with previously published data including TCGA and support the need to further explore the biologic relevance of these alterations in HNSCC.

Incidence trends of squamous cell carcinoma of the head and neck (SCCHN) in the aging population: A SEER based analysis from 2000-2016

e18522

Background: SCCHN is more prevalent in the elderly. As the United States population ages, it is increasingly important to evaluate the change in the incidence of SCCHN in this population. Methods: This was a retrospective study using data from a population-based cancer registry (Surveillance, Epidemiology, and End Results) to identify patients ≥65 years old with the diagnosis of SCCHN between the years 2000-2016. The subgroups of oral cavity (OCC)and oropharynx cancer (OPC) were also analyzed independently. The incidence per year was calculated and joinpoint detection was used to identity significant changes in incidence trends. Annual percent change (APC) was detected to determine if the incidence trend was statistically significant. The study population was further stratified by sex. Results: For all sites, a joinpoint was found in 2003 with a statistically significant decrease in APC in incidence for males from 2000-2003 of -2.45%. For OCC, there was a joinpoint in 2005 with a statistically significant increase in APC in incidence for male patients of 1.41%. For (OPC), no joinpoint was found, but there was a statistically significant increase in APC in incidence for males of 3.41%. For females no joinpoint was found, but for OCC there was a statistically significant decrease in APC in incidence of -0.40%. Conclusions: In patients ≥ 65 years old the trend in incidence rate for all SCCHN sites stratified by sex has decreased between 2000-2016. However, for males the annual percent change in incidence has increased for OCC from 2005-2016 and for OPC from 2000-2016. [Table: see text]

Small Cell and Squamous Cell Carcinomas of the Head and Neck: Comparing Incidence and Survival Trends Based on Surveillance, Epidemiology, and End Results (SEER) Data

BACKGROUND

Small cell carcinomas of the head and neck (SmCCHNs) are rare neoplasms with an unfavorable prognosis. Population-based data describing survival and prognostic factors for SmCCHN are limited.

METHODS

Data were obtained from the U.S. National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database for 1973-2013. Patient and tumor-related characteristics for SmCCHN were compared with those for squamous cell carcinoma of the head and neck (SCCHN). Survival was compared by constructing Kaplan-Meier curves and Cox proportional hazard models with and without propensity score matching.

RESULTS

The data set included 609 SmCCHN and 227,943 SCCHN cases. Both histological subtypes were more common in men than women and more common in white patients. SmCCHN was most likely to originate in the larynx, glottis and hypopharynx, or salivary glands and to present with more advanced stage and grade. SCCHN was most likely to originate in the oral cavity and was found infrequently in the salivary glands. Overall 5- and 10-year survival estimates were 27% and 18% for SmCCHN and 46% and 31% for SCCHN, respectively. In multivariable survival analyses adjusting for age, sex, race, marital status, year of diagnosis, stage, grade, and receipt of radiation, the hazard ratio (HR) comparing SmCCHN with SCCHN was 1.53 with a 95% confidence interval (CI) from 1.39 to 1.68. Average 5-year survival varied widely between the histologic types when comparing tumor sites: 14.5% for SmCCHN versus 48.9% for SCCHN in the oropharynx. In propensity score matched analyses, the corresponding HR was 1.27 (95% CI, 1.15-1.40).

CONCLUSION

Compared with SCCHN, SmCCHN carries a worse survival and is more likely to present with more advanced stage.

IMPLICATIONS FOR PRACTICE

Small cell carcinoma of the head and neck (SmCCHN) is a rare subtype of head and neck cancer. In this Surveillance, Epidemiology, and End Results (SEER) data analysis, the characteristics and survival of SmCCHN are compared with those of the common squamous cell carcinoma of the head and neck. Results show that SmCCHN carries a worse prognosis and tends to present at a more advanced stage; SmCCHN also is ten times more likely to originate from the salivary glands. These findings may have implications for clinical practice, as location of the tumor may strongly associate with the pathologic diagnosis. If a SmCCHN is diagnosed, a disseminated disease is likely; hence vigilance in staging procedures is indicated.

Socioeconomic contributions to clinical outcome by HPV status in squamous cell carcinomas of the head and neck (SCCHN): An analysis of NCDB

e18214

Background: HPV association remains one of the most important predictors of clinical outcome in SCCHN. We aimed to determine whether the relationship between HPV status and overall survival (OS) varied by certain socioeconomic factors. Methods: Data were obtained from the National Cancer Database (NCDB). We examined the relationship between OS and HPV status, controlling for demographics and socioeconomic variables (insurance, income, education, urban/rural, great circle distance, and/or distance to treatment facility of 0-10, 10-50, and > 50 miles). Results: HPV status modified the relationship between insurance status (p = 0.011), urban/rural residence (p = 0.041), and overall survival, controlling for age, race, sex, and clinical stage. Whereas for HPV- patients, government insurance conferred a lower risk of death compared to no insurance (HR: 0.86, 95% CI: 0.75-0.99, p = 0.038); this finding did not hold for patients with HPV related disease (HR: 0.97, 95% CI: 0.80-1.18, p = 0.781). For patients with HPV related SCCHN, those living in rural areas have significantly higher risk of death compared to those living in metro areas (HR: 1.55, 95% CI: 1.17-2.05, p = 0.002), which did not hold for patients with HPV unrelated SCCHN (HR: 0.94, 95% CI: 0.68-1.30, p = 0.703). Conclusions: Despite HPV’s prospective prognostication, patients with HPV + SCCHN who live in rural environments have a higher risk of death likely from lack of physical access to care. This finding did not hold for HPV negative population, presumably because of their worse outcomes at baseline, and their struggle for access to care regardless of physical location.

Phase 1b study of chemoprevention with green tea polyphenon E (PPE) and epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (Erlotinib) in patients (pts) with advanced premalignant (AP) lesions of the head and neck

6049

Background: Based on the strong synergistic effects between green tea polyphenon E (PPE) and EGFR-TKI in our preclinical studies (Int J Cancer, 2008; Cancer Prev Res, 2009; JCO, 2009), we conducted a phase 1b study with PPE and erlotinib combination for APL (mild-, moderate-, severe-dysplasia or carcinoma in situ [CIS]) of the oral cavity and larynx from 2/2011 to 11/2017 at Emory Winship Cancer Institute. Methods: All pts were enrolled after signing the IRB approved Informed Consent Form. Tissue biopsy before and at 6-months (6-M) treatment was mandatory, and cytobrushed samples of the APL and normal buccal mucosa at 3-, 6-, and 12-M were obtained for biomarker studies. Treatment included fixed dose of PPE (200 mg, P.O.,TID) and dose escalation of erlotinib P.O., (50mg [level 1], 75mg [level 2] and 100mg [level 3]) for 6-M. The primary endpoint was safety and toxicity, and secondary endpoints were evaluation of pathologic responses, cancer free survival (CFS) and biomarker modulation. Results: Out of 27 enrolled pts, 6 control subjects for biomarker studies, 2 ineligible, and 19 were treated with PPE and erlotinib for 6-M. Clinical characteristics of treated patients included median age, 63 yrs. (range,33-78); 9 M/10 F; 10 former or current smokers/9 never smokers; 15 severe dysplasia or CIS, 2 moderate dysplasia, 2 mild dysplasia; 13 had surgical resection; 17 oral cavity primary; and 2 at larynx. 3 pts were treated at dose level 1, 4 at level 2, and 12 at level 3. Toxicity (G0 or G1 excluded) were: skin rash (1 G3, 1 G2), pruritus/dry skin (1 G2), fatigue (1 G2), diarrhea (1 G2), epistaxis (1 G2), and hypertension (2 G3, 1 G2). Skin rash (associated with erlotinib) may be DLT and MTD has not been reached. The recommend doses for phase 2 or 3 studies will be PPE 200mg TID plus erlotinib 100mg QD. 17 pts were assessed for pathologic responses at 6-M: pCR 7/17 (41%), pPR 2/17 (12%), pSD 5/17 (29%) and pPD (3/17 (18%). The median follow up was 32 months. Median CFS has not been reached. 16 pts are alive at the time of data analyses and 1 pt died (by noncancerous reason). Biomarker studies are ongoing for tissues and/or cytobrushed samples. Conclusions: The treatment of the combination of green tea PPE plus erlotinib for 6-M was well tolerated in pts with APL of the head and neck, and showed significant pathologic response rates (pCR and pPR, 53%). This combination therefore deserves further investigation for efficacy testing. Clinical trial information: NCT01116336.

Factors associated with metastatic presentation in HPV-related squamous cell carcinoma of the head and neck (SCCHN): A National Cancer Database (NCDB) analysis

e18213

Background: Metastasis is an ominous sign in SCCHN. Human papillomavirus (HPV) infection-associated SCCHN cancers tend to have a distinct prognosis. Factors that are associated with metastatic disease at the time of presentation and diagnosis in patients with HPV-related SCCHN tumors were examined. Methods: NCDB was queried to assess 12,857 patients with HPV-related oropharyngeal carcinomas (HPVOPCA) and 952 patients with HPV related non-oropharyngeal carcinomas (HPVNOPCA) diagnosed between between 2010-2014 with non-missing survival or M stage. Rate of metastases at presentation was analyzed using clinical M stage. Multivariable analysis was performed evaluating race, ethnicity, sex, age, facility location, facility type, insurance status, income, education, urban/rural location, surgery, radiation, and chemotherapy using logistic regression. Results: In both HPVOPCA and HPVNOPCA, over 90% of patients were white. Private insurance was carried by 64% and 47% of patients with HPVOPCA and HPVNOPCA, respectively. HPVOPCA cancer was located in the tonsil in 47% of cases. Patients with HPVOPCA were more likely to present with advanced nodal disease than patients with HPVNOPCA. For both HPVOPCA and HPVNOPCA, there was no meaningful difference in the rate of distant metastasis at presentation in facility type or location, sex, race, Hispanic ethnicity, or urban rural location. For HPVOPCA, there were significantly lower odds of metastasis in privately insured patients vs. uninsured patients (HR: 0.35, 95% CI: 0.21-0.59, p < 0.001), and higher odds of metastasis for those living in census tracts with the lowest rates of high school graduates vs. those living in census tracts with the highest rates of high school graduates (HR: 1.82, 95% CI: 1.07-3.09, p = 0.026). For HPVNOPCA, patients living in census tracts with the lowest rates of high school graduates were less likely to develop metastasis compared to those living in census tracts with the highest rates of high school graduates (p = 0.031). Conclusions: This large retrospective analysis identifies likely modifiable risk factors for metastatic presentation in HPV-related SCCHN. Health policies and educational interventions may result in modifications of these patterns.

A randomized phase II study of tremelimumab and durvalumab with or without radiation for patients with relapsed small cell lung cancer (SCLC)

8515

Background: The combination of PD-1 and CTLA-4 inhibition has demonstrated activity in the second line therapy setting for SCLC. Radiotherapy enhanced the effectiveness of immunotherapy in NSCLC. We conducted this signal finding study to assess the efficacy of combined ICI with or without radiation in relapsed SCLC. Methods: Patients with relapsed SCLC who have received not more than 2 lines of therapy were enrolled and randomized to either Arm A: [Tremelimumab (T) 1500mg/durvalumab (D) 75mg i.v. every 4 weeks without SBRT] or Arm B: T/D with immune sensitizing SBRT to one selected tumor site (9 Gy x 3 fractions). Treatment continued until progression or maximum of 2 years. Paired tumor biopsies and serial samples of peripheral blood were employed for correlative endpoints (changes in intratumoral and circulating lymphocyte repertoire and immune cytokines). The study was designed to show a promising efficacy signal in either Arm with a hypothesized median PFS of 7 months (10 patients give 87% power at 1-sided alpha of 0.1). Results: Study randomized 17 patients to Arm A (8 patients) or B (9 patients); median age of 70 yrs; females 41.2%; White, 70%, Black 17.6%. Best response in 14 overall evaluable patients was PD in 9 (64.3%), PR in 2 (14%) and SD in 3 (21.4%); median PFS of 2.76 months and OS of 4.47 months. There was no significant difference in efficacy between Arms A and B but a trend of improved PFS and OS with T/D plus SBRT (see table): Median PFS of 2.1 vs. 3.3 months [HR: 2.44 (0.75-7.93); p = 0.122] and median OS of 2.6 vs. 5.7 months [HR: 1.50 (0.45-4.99); p = 0.5068]. Observed grade ≥ 3 adverse events were: Cytopenia (4), Dyspnea (1), and endocrine disorders (3) in Arm A; diarrhea (3) and cytopenias (1) in Arm B. There was an increase in circulating CD8(+) lymphocytes on treatment versus baseline in patients with objective tumor response. Conclusions: The study did not show sufficient signal of efficacy for ICI with or without SBRT in relapsed SCLC. Detailed result of the biomarker analysis will be available at the meeting. Clinical trial information: NCT02701400. [Table: see text]

Comparison of the seventh and eighth editions of the American Joint Committee on Cancer (AJCC) staging for oropharyngeal squamous cell carcinomas (OPSCC): A Surveillance, Epidemiology and End Results Program (SEER) database analysis

e17538

Background: The recently released eighth edition of the American Joint Committee on Cancer (AJCC) Staging Manual, Head and Neck Section, incorporates significant changes to the prior seventh edition. The changes reflect the improved understanding of tumor biology, prognostic factors and molecular markers that effect outcomes in Head and Neck cancers. A key update restages OPSCC by human papilloma virus (HPV) positive and negative cancers as data demonstrated that these tumors have significantly different biology and outcomes. Methods: Using SEER data from 2004 – 2014, we identified male patients with squamous cell carcinomas of the tonsil, base of tongue and soft palate aged between 21 and 64 years old (those clinical characterizes were considered as surrogate markers for HPV positive status). We classified them by the AJCC 8th edition staging for HPV positive OPSCC and by AJCC 7th edition staging. The prediction performance by two staging editions were compared regarding overall survival (OS) and Disease free survival (DFS). Kaplan-Meier method and Cox proportional hazard model were applied, and the discrimination performance was measured by the concordance statistics (C-statistics). Results: A total of 8202 eligible patients were included in the analysis with a median follow up period of 51 months. 7415 (90.4%) patients had previously received radiation and 7038 (85.8%) patients had previously received chemotherapy. The median age of patients was 56 years. Distribution of stage I disease increased from 2% to 19.6% in AJCC 8th edition. 10-year overall survival (OS) for AJCC 8th stages I (74%), II (78%), III (55%) and IV (32%). Using Stage I as reference, the hazard ratio for stage II, III, and IV is 0.98 (95%CI: 0.87-1.09), 2.29 (95%CI: 2.04-2.57), and 5.88 (95%CI: 4.96-6.98). Similar results were noted for ten year disease free survival. The C-statistics measured overall discrimination for 8th edition is 0.68 and 0.63 for the 7th edition (P < 0.001). Conclusions: Based on this SEER analysis, the overall performance of discrimination improved from AJCC 7th to 8th edition; but in this study population, AJCC 8th edition does not distinguish stage I and II sufficiently as expected as it does for stages III and IV disease. Limitations of the SEER database include the surrogate for P16 status and under reported and incomplete data.

Measurement of circulating tumor cells in squamous cell carcinoma of the head and neck and patient outcomes

OBJECTIVES

We report the outcomes of patients with squamous cell carcinoma of the head and neck (HNSCC) whose circulating tumor cells (CTCs) were quantified using surface-enhanced Raman scattering (SERS) nanotechnology.

METHODS

SERS tagged with EGF was used to directly measure targeted CTCs. Patient charts were retrospectively reviewed. An optimal cut point for CTCs in 7.5 ml of peripheral blood predictive of for distant metastasis-free survival (DMFS) was identified by maximizing the log-rank statistic. An ROC analysis was also performed.

RESULTS

Of 82 patients, 13 experienced metastatic progression. The optimal cut point for DMFS was 675 CTCs (p = 0.047). For those with distant recurrence (n = 13) versus those without distant recurrence (n = 69), the CTC cut point which results in the largest combined sensitivity and specificity values is also 675 (sensitivity = 69%, specificity = 68%).

CONCLUSION

Liquid biopsy techniques in HNSCC show promise as a means of identifying patients at greater risk of disease progression.

Adenosquamous Carcinoma of the Esophagus: An NCDB-Based Investigation on Comparative Features and Overall Survival in a Rare Tumor

OBJECTIVES

Esophageal adenosquamous carcinoma (ASC) is a rare tumor with characteristics of adenocarcinoma (AC) and squamous cell carcinoma (SCC), the two most common esophageal cancers. Its behavior is aggressive but poorly understood. Using the National Cancer Database (NCDB), the clinical features and overall survival of ASC were compared with AC and SCC.

METHODS

The NCDB was queried for patients with esophageal ASC, AC, and SCC. Univariate association of histology with patient characteristics and overall survival were analyzed and socioeconomic characteristics were balanced.

RESULTS

Clinical M stage was 0 in a significantly lower proportion of ASC (69.0%) than in AC (70.9%) or SCC (75.6%) (p < 0.001). Median survival was lower in patients with ASC (9.6 months) than with AC (13.5) or SCC (9.7) and 2-year OS was lower in patients with ASC (23.8%) than with AC (34.6%) or SCC (26.5%) (p < 0.001). The OS hazard ratio for ASC was 1.14 when compared to AC (95% CI = 1.016-1.267, p = 0.025) and 1.10 when compared to SCC, but the latter was not significant (95% CI = 0.980-1.222, p = 0.111).

CONCLUSION

ASC is a rare tumor among esophageal carcinomas with a greater burden of metastatic disease than AC or SCC and worse OS than AC.

Small cell carcinoma of the head and neck: Incidence and survival trends based on the Surveillance and Epidemiologic and End Results (SEER) analysis

e17508

Background: Small cell carcinomas of the head and neck (SmCCHN) are rare neoplasms with an unfavorable prognosis. Population based data describing survival and prognostic factors for this malignancy are limited. Methods: Data was obtained from the US National Cancer Institute’s Surveillance, Epidemiology and End Results (SEER) database for the period 1973-2013. Patient and tumor related characteristics for SmCCHN were compared with squamous cell carcinomas (SCC) of the same anatomic sites. Survival for the two groups was compared by constructing Kaplan-Meier curves and Cox proportional hazard models with and without propensity score matching. Cox models results were expressed as hazard ratios (HR) and the corresponding 95% confidence interval (CI). Results: The dataset included 609 SmCCHN and 227943 cases of SCCHN. SCCHN patients with SmCCHN included significantly greater proportions of females and whites. SmCCHN was more likely to originate in the salivary glands and present with more advanced stage and grade. The overall 5 year and 10 year survival estimates were 27% and 18%, respectively. Corresponding values for SCCHN were 46% and 31%. The multivariable analyses adjusting for age, sex, race, marital status, year of diagnosis, stage, grade and receipt of radiation, the HR comparing SmCCHN to SCCHN was 1.53 (95% CI: 1.39-1.68). Elderly, male, black and not married persons had worse prognosis compared to their respective reference groups. Other factors independently associated with lower survival included more advanced stage and tumor grade, and earlier decades of diagnosis. In the propensity score matched analyses the corresponding HR was 1.27 (95% CI: 1.15-1.40). Conclusions: Compared to SCCHN, SmCCHN in addition to carrying a worse survival, is more likely to originate in the salivary glands, present with more advanced stage, and affect females and whites.

FGFR3 correlation with mutant p53 and its prognostic value in oropharyngeal squamous cell carcinoma (OPSCC)

6057

Background: Fibroblast growth factor receptor 3 (FGFR3) is expressed in squamous cell carcinoma of the head and neck (SCCHN) including oropharyngeal squamous cell carcinoma (OPSCC) and is a potential therapeutic target. Information on its prognostic value and its correlation with other relevant cancer related proteins is limited. Methods: We performed immunohistochemistry (IHC) analyses of p16, mutant p53 (mp53), and FGFR3 on 221 retrospectively collected OPSCC tissue samples. mp53, and FGFR3 were semi-quantified as weighted index [WI = % positive x intensity (0. 1+, 2+, and 3+)]. Correlations of FGFR3 WI with p16 status, and mp53 WI were analyzed. Association of FGFR3 with disease-free survival (DFS) or overall survival (OS) was assessed. Results: A total of 144/221 (65%) were p16 +, 93/172 (54%) had mp53, and 140/221 (63%) expressed FGFR3. FGFR3 was highly correlated with mp53 (p < 0.001), which was true in both p16 + and – OPSCC (p < 0.0001 and p = 0.0006, respectively).mp53 level was significantly lower in p16 positive versus p16 negative group (p < 0.0001). Univariate analysis revealed an association of p16 negative and high mp53 with worse OS (p < 0.001 and p < 0.001, respectively) and DFS (p < 0.001 and p = 0.004, respectively). FGFR3 was associated with worse OS and DFS (p = 0.014 and p = 0.047, respectively). On multivariable analysis FGFR3 was associated with worse DFS (p = 0.005), but not OS. Kaplan-Meier plot using medians of both FGFR3 and mp53 as the cut-off values showed that higher FGFR3 and mp53 correlated to worst DFS (p = 0.025) and OS (p = 0.009). Conclusions: Our results suggest that FGFR3 is associated with mp53 and p16 – OPSCC and correlates with worse clinical outcome. The biologic relation of FGFR3 and mp53 in OPSCC deserves further investigation. (This research was supported by a grant NCI R21 CA182661-01A1to NFS and GZC).

Molecular signatures of class II HLA and p-16 status as an immune-based classification of OPSCC relying on known predictors of sensitivity to PD-1 blockade

6052

Background: PD-1 inhibitors are known to have significant clinical activity in head and neck squamous cell cancer (SCCHN); there is, however, no selection criterion for SCCHN patients who may benefit from PD-1 inhibition. Utilizing RNA-seq analysis we explored a set of human genes encoding leukocyte antigens (HLAs) as part of a 37-gene panel predictive of response in melanoma patients to PD-1 inhibitors (Chen et al, Cancer Discov. 2016 Aug;6(8):827-37).We investigated whether this panel could define an immune-based classification of oropharyngeal squamous cell carcinoma (OPSCC). Methods: We have applied a minimal mutation and copy number content (151 genes) using an Agilent Clearseq DNA and an extensive Illumina Truseq RNA panel providing key information on gene fusions, differential gene expression, coding mutation and metagenomics on 47 SCCHN FFPE samples including 27 OPSCC. We performed an unsupervised hierarchical clustering of the samples. Two clusters with high and low expression were noted. Fisher’s exact test was performed to determine if the samples in each clusters were associated with p16 as a surrogate marker for HPV status. The same procedure was repeated on Level 3 transcriptome data from the TCGA via GDC data portal. Results: A set of fourteen immune related HLA antigen genes were identified within the 37-gene panel predictive to response to PD-1 inhibitors in p16+ versus - OPSCC (p = 0.015).We applied the same set of immune related HLA genes on the 103 patient samples from TCGA with known p16 status. When applied on all samples, there was no correlation between the HLA gene expression and p16 status (p = 0.1366); however, when restricted to OPSCC patients there was a high correlation with p16 status (p = 0.0047). Conclusions: We have identified a set of immune related HLA type II genes that are over-expressed in p16 positive OPSCC. This opens the door for further evaluation of these genes to better understand the immune related factors affecting the biology of HPV-associated OPSCC and its response to PD-1 inhibitors. (This research was supported by a grant NCI R21 CA182661-01A1to NFS and GZC).

Landscape of genetic alterations in oropharyngeal squamous cell carcinoma (OPSCC) based on RNA-seq and WES analysis of FFPE samples and correlation with data from TCGA

e17527

Background: Whole human exome sequencing (WES) has identified well characterized somatic mutations (such as TP53, CDKN2A, PIK3CA and HRAS) in patients with squamous cell carcinoma of the head and neck (SCCHN). We sought to optimize a combined RNA-seq and WES approach for identifying actionable mutations and gene expression signatures in p16 + versus - OPSCC. Methods: Relying on formalin fixed and paraffin embedded (FFPE) samples we applied a minimal mutation and copy number content (151 genes) on DNA and an extensive RNA panel on a total of 27 OPSCC (22 p16 +, and 5 p16 -). SAMSeq was used to identify the differentially expressed genes. Unsupervised hierarchical clustering of the TCGA OPSCC samples with available p16 status (n = 31) was performed for external validation of the results. Statistical significance was further tested by Fisher’s exact test. Results: We identified a gene signature differentially expressed in p16+ and p16- OPSCC. External validation showed a significant association between gene expression and p16 status (P = 0.00033). We did not however find an association with mutation burden and smoking history. A number of pathways associated with this gene signature such as NCAM1 may have relevant biologic implications in OPSCC. Conclusions: Our results underscore the reliability of integrating data from FFPE samples in distinguishing gene signatures characteristic of p16 + versus p16- OPSCC; these signatures need to be further explored for their biologic relevance in OPSCC (This research was supported by a grant NCI R21 CA182661-01A1to NFS and GZC).

Intact APM and PD-1:PD-L1 pathway upregulation in HIV-infected head and neck cancer patients

6058

Background: HIV-infected individuals have a higher incidence of oral infection with human papillomavirus (HPV) and possibly a higher incidence of head and neck cancer (HNC). Whether this observation reflects defects in the ability of this Òimmune-compromisedÓ patient population to mount sufficient tumor specific immune responses and/or reflects activation of immune escape mechanisms is not known. To address this question, we investigated the expression of HLA class I antigen processing machinery (APM) components and PD-1:PD-L1 pathway activation in HIV(+) HNC patients. Methods: 62 HIV(+) HNC patients diagnosed between 1991-2011 from five tertiary care referral centers in the United States and matched HIV(-) HNC controls were identified. HLA class I APM component, PD-1, and PD-Ll expression were analyzed by immunohistochemical staining. Clinical data was abstracted from the medical records. Results: 44 of 62 (71%) HIV(+) HNC cases were matched based on gender, age ( < 10 years), and anatomic sub-site to HIV(-) HNC patients. There was no significant difference between the cases and controls in HLA-A, HLA-B/C, LMP2, and TAP1, as well as PD-1 and PD-L1 expression. Overall, 62% of all subjects had high PD-1 expression and 82% of the subjects expressed PD-L1. HLA-A, HLA-B/C, and LMP2 expression was significantly correlated with moderate to high PD-1 expression in the HIV(+) HNC cases (p = 0.004, p = 0.026, and p = 0.006, respectively) but not in the HIV(-) controls. Similarly, HLA-A expression was also significantly associated with PD-L1 expression only in the HIV(+) HNC cases (p = 0.029). Conclusions: No defects were detected in the expression of the HLA class I APM components tested. PD-1:PD-L1 pathway was found to be upregulated in both HIV(+) and HIV(-) HNC patients. Our data suggest that recently approved anti-PD-1 immunotherapy should not exclude HIV(+) patients.

Institutional treatment volume and outcomes in salivary gland cancer

6082

Background: Salivary gland cancer (SGC) is a rare malignancy and has been understudied in the literature. Given the rarity of SGC, we sought to compare outcomes of SGC within high volume (HV) and low volume (LV) centers, utilizing the National Cancer Database (NCDB). Methods: The NCDB was queried from 2004 to 2014 for SGC using ICD-O-3 codes for the 4 most common histologies: (mucoepidermoid carcinoma (ME), adenoid cystic carcinoma (AdCC), acinic cell carcinoma(ACC), and adenocarcinoma NOS(A)) for consistency. The number of cases treated at each facility was calculated, and the threshold for distinguishing high volume vs. low volume was determined using the 80th percentile of the number of cases treated per facility. Patient characteristics were compared using chi-squared tests and ANOVA. Overall survival was estimated using the Kaplan-Meier method, and was compared using log-rank tests. Statistical analyses were performed using SAS 9.4. Results: There were 31,189 SG patients overall; 16,373 were either ME, AdCC, ACC, or A and were included in the analysis. There were 6534 patients treated in LV (41%) and 9839 in HV (59%). HV centers were more likely to be academic and integrated network cancer programs (p < .001). The median age for LV vs. HV was 61y vs. 58y (p < .001), 49% vs. 47% male (p = .007), and 84% vs. 80% White (p < .001), respectively. Patients presented with slightly more advanced disease at HV, with 24.4% having stage 3-4 disease, vs 23% in LV (p = .004). The majority of patients underwent surgical resection (57% LV vs. 64% HV). HV had more negative margins (59% vs 55%, p < .001), more neck dissections (72% vs. 64%, p < .001), and longer hospital stays (mean 2.21d vs 1.55d, p < .001). More patients in LV received radiation than HV (55% vs. 52%, p < .001), but there was no difference in chemotherapy use (p = 0.650). Patients had better survival (m1 disease excluded) in HV as compared to LV (5-year OS HV 77.4% vs LV 75.5%, HR 0.89, p = 0.002). Conclusions: Our results indicate that survival of SGC is affected by institutional treatment volume and the significant differences in treatment at LV vs. HV institutions urges for the need of better standardization of care.

Phase IB study of induction chemotherapy with XELOX, followed by radiation therapy, carboplatin, and everolimus in patients with locally advanced esophageal cancer (EC)

e15607

Background: Preclinical studies have shown synergy between everolimus, an mTOR inhibitor, radiation and platinum agents in EC. We conducted a multi-institutional phase IB trial to determine the recommended phase II dose (RP2D) of concurrent everolimus with carboplatin and radiation in non-metastatic EC pts. Methods: Patients with untreated, localized EC and ECOG performance status 0-1 were eligible. Following two cycles of induction Capecitabine/Oxaliplatin (XELOX), pts without evidence of disease progression, received concurrent chemoradiation (total dose: 50.4Gy in 28 fractions), weekly carboplatin (AUC = 2), and escalating doses of everolimus. A standard 3+3 dose escalation design was used. Results: Nineteen patients were enrolled. There were two screen failures (thrombocytopenia, metastases) and 4 pts were removed due to poor tolerance of XELOX (2 pts) or disease progression (2 pts). A total of 13 pts with stage II/III (6/7) EC completed concurrent therapy. Median age 58 (44-71yrs), 85% males; all had adenocarcinoma deemed resectable. One pt at dose level 1 (2.5 mg/QOD), was replaced due to ongoing anxiety. One of 6 pts had a DLT (bowel ischemia). At dose level 2 (2.5mg/QD), 2 out of 6 patients had a DLT (fever with neutropenia and nausea). The RP2D of everolimus was 2.5 mg QOD. Clinically relevant ≥ grade 3 toxicities included lymphopenia (25%), dehydration (12%), fatigue, leukopenia, hyponatremia, abdominal pain, vomiting (each 6%). R0 resection was achieved in 100%; a pathologic response rate (RR) of 40% and a pathologic complete response (pCR) rate of 23% were observed. The 2-year PFS and OS were 50% and 49.6% respectively. Conclusions: The RP2D of everolimus with concurrent weekly carboplatin and radiation is 2.5 mg QOD. Despite the 100% R0 resection rate, the pCR and OS rates were within the expected historical controls. (The study was funded by Novartis Pharmaceuticals) Clinical trial information: NCT01490749.

RSK2 signals through stathmin to promote microtubule dynamics and tumor metastasis

Metastasis is responsible for >90% of cancer-related deaths. Complex signaling in cancer cells orchestrates the progression from a primary to a metastatic cancer. However, the mechanisms of these cellular changes remain elusive. We previously demonstrated that p90 ribosomal S6 kinase 2 (RSK2) promotes tumor metastasis. Here we investigated the role of RSK2 in the regulation of microtubule dynamics and its potential implication in cancer cell invasion and tumor metastasis. Stable knockdown of RSK2 disrupted microtubule stability and decreased phosphorylation of stathmin, a microtubule-destabilizing protein, at serine 16 in metastatic human cancer cells. We found that RSK2 directly binds and phosphorylates stathmin at the leading edge of cancer cells. Phosphorylation of stathmin by RSK2 reduced stathmin-mediated microtubule depolymerization. Moreover, overexpression of phospho-mimetic mutant stathmin S16D significantly rescued the decreased invasive and metastatic potential mediated by RSK2 knockdown in vitro and in vivo. Furthermore, stathmin phosphorylation positively correlated with RSK2 expression and metastatic cancer progression in primary patient tumor samples. Our finding demonstrates that RSK2 directly phosphorylates stathmin and regulates microtubule polymerization to provide a pro-invasive and pro-metastatic advantage to cancer cells. Therefore, the RSK2-stathmin pathway represents a promising therapeutic target and a prognostic marker for metastatic human cancers.

The Synthesis and Properties of Solution Processable a Red Phosphorescent Iridium(III) Complex with Alkyl Group

The (TMP-HT)2Ir(acac) was synthesized with 2-bromo-4-(trifluoromethyl)pyridine and 5-hexyl-2-thiopheneboronic acid pinacol ester for organic light-emitting diodes (OLEDs). This material was designed on the basis of Gaussian modeling program results. The ligands have both the electron donor and acceptor in a molecule. There are pyridyl group which decrease electron density and thiophene group which increase electron density. Therefore, it showed intramolecular charge transfer (ICT) property. For solution process, the ligand have a alkyl group which has hydrophobic property. The (TMP-HT)21r(acac) was synthesized by Suzuki coupling reaction and Nonoyama reaction. The (TMP-HT)21r(acac) emitted at approximately 600 nm. The device structures were ITO/PEDOT (500 Å)/TFB (170 Å)/PVK:PBD (40%): (TMPHT)21r(acac) (300 Å:10%)/BH:BD5% (150 Å)/L201(50 Å)/Liq(200 Å)/Al. Electroluminescent properties were observed with devices doped with various doping concentrations.

Hypotonic stress induces RANKL via transient receptor potential melastatin 3 (TRPM3) and vaniloid 4 (TRPV4) in human PDL cells

Bone remodeling occurs in response to various types of mechanical stress. The periodontal ligament (PDL) plays an important role in mechanical stress-mediated alveolar bone remodeling. However, the underlying mechanism at the cellular level has not been extensively studied. In this study, we investigated the effect of shear stress on the expression of bone remodeling factors, including receptor activator of nuclear factor-kappa B (NF-κB) ligand (RANKL) and osteoprotegerin (OPG), as well as its upstream signaling pathway in primary human PDL cells. We applied hypotonic stress to reproduce shear stress to PDL cells. Hypotonic stress induced the messenger RNA (mRNA) and protein expression of RANKL but not OPG. It also increased intracellular Ca(2+) concentration ([Ca(2+)]i). Extracellular Ca(2+) depletion and nonspecific plasma membrane Ca(2+) channel blockers completely inhibited the increase in both [Ca(2+)]i and RANKL mRNA expression. We identified the expression and activation of transient receptor potential melastatin 3 (TRPM3) and vaniloid 4 (TRPV4) channels in PDL cells. Pregnenolone sulfate (PS) and 4α-phorbol 12, 13-didecanoate (4α-PDD), which are agonists of TRPM3 and TRPV4, augmented Ca(2+) influx and RANKL mRNA expression. Both pharmacological (2-aminoethoxydiphenyl borate [2-APB], ruthenium red [RR], ononetin [Ono], and HC 067047 [HC]) and genetic (small interfering RNA [siRNA]) inhibitors of TRPM3 and TRPV4 reduced the hypotonic stress-mediated increase in [Ca(2+)]i and RANKL mRNA expression. Our study shows that hypotonic stress induced RANKL mRNA expression via TRPM3- and TRPV4-mediated extracellular Ca(2+) influx and RANKL expression. This signaling pathway in PDL cells may play a critical role in mechanical stress-mediated alveolar bone remodeling.

Effect of reactive monomer on PS-b-P2VP film

Poly(styrene-b-2-vinyl pyridine) (PS-b-P2VP) lamellar film which is hydrophobic block-hydrophilic polyelectrolyte block polymer of 52 kg/mol-b-57 kg/mol and PS-b-P2VP film with reactive monomer (RM257) were prepared for photonic gel films. The lamellar stacks, which is alternating layer of hydrophilic and hydrophobic moiety of PS-b-P2VP, were obtained by exposing the spin coated film under chloroform vapor. The lamellar films were quaternized with 5 wt% of iodomethane diluted by n-hexane. We reported about the influence of reactive monomer on those photonic gel films. Added reactive monomer photonic gel film had higher absorbance than pure photonic gel films. As a result the photonic gel film with RM had more clear color. The lamellar films were swollen by DI water, ethanol (aq) and calcium carbonate solution. The band gaps of the lamellar films were drastically shifted to longer wavelength swollen by calcium carbonate solution. And the lamellar films were shifted to shorter wave length swollen by ethanol. So each lamellar film showed different color.

Glechoma hederacea Suppresses RANKL-mediated Osteoclastogenesis

Glechoma hederacea (GH), commonly known as ground-ivy or gill-over-the-ground, has been extensively used in folk remedies for relieving symptoms of inflammatory disorders. However, the molecular mechanisms underlying the therapeutic action of GH are poorly understood. Here, we demonstrate that GH constituents inhibit osteoclastogenesis by abrogating receptor activator of nuclear κ-B ligand (RANKL)-induced free cytosolic Ca(2+) ([Ca(2+)]i) oscillations. To evaluate the effect of GH on osteoclastogenesis, we assessed the formation of multi-nucleated cells (MNCs), enzymatic activity of tartrate-resistant acidic phosphatase (TRAP), expression of nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), and [Ca(2+)]i alterations in response to treatment with GH ethanol extract (GHE) in primarily cultured bone marrow-derived macrophages (BMMs). Treatment of RANKL-stimulated or non-stimulated BMMs with GHE markedly suppressed MNC formation, TRAP activity, and NFATc1 expression in a dose-dependent manner. Additionally, GHE treatment induced a large transient elevation in [Ca(2+)]i while suppressing RANKL-induced [Ca(2+)]i oscillations, which are essential for NFATc1 activation. GHE-evoked increase in [Ca(2+)]i was dependent on extracellular Ca(2+) and was inhibited by 1,4-dihydropyridine (DHP), inhibitor of voltage-gated Ca(2+) channels (VGCCs), but was independent of store-operated Ca(2+) channels. Notably, after transient [Ca(2+)] elevation, treatment with GHE desensitized the VGCCs, resulting in an abrogation of RANKL-induced [Ca(2+)]i oscillations and MNC formation. These findings demonstrate that treatment of BMMs with GHE suppresses RANKL-mediated osteoclastogenesis by activating and then desensitizing DHP-sensitive VGCCs, suggesting potential applications of GH in the treatment of bone disorders, such as periodontitis, osteoporosis, and rheumatoid arthritis.

A phase 1 Bayesian dose selection study of bortezomib and sunitinib in patients with refractory solid tumor malignancies

BACKGROUND

This phase 1 trial utilising a Bayesian continual reassessment method evaluated bortezomib and sunitinib to determine the maximum tolerated dose (MTD), dose-limiting toxicities (DLT), and recommended doses of the combination.

METHODS

Patients with advanced solid organ malignancies were enrolled and received bortezomib weekly with sunitinib daily for 4 weeks, every 6 weeks. Initial doses were sunitinib 25 mg and bortezomib 1 mg m(-2). Cohort size and dose level estimation was performed utilising the Escalation with Overdose Control (EWOC) adaptive method. Seven dose levels were evaluated; initially, sunitinib was increased to a goal dose of 50 mg with fixed bortezomib, then bortezomib was increased. Efficacy assessment occurred after each cycle using RECIST criteria.

RESULTS

Thirty patients were evaluable. During sunitinib escalation, DLTs of grade 4 thrombocytopenia (14%) and neutropenia (6%) at sunitinib 50 mg and bortezomib 1.3 mg m(-2) were seen. Subsequent experience showed tolerability and activity for sunitinib 37.5 mg and bortezomib 1.9 mg m(-2). Common grade 3/4 toxicities were neutropenia, thrombocytopenia, hypertension, and diarrhoea. The recommended doses for further study are bortezomib 1.9 mg m(-2) and sunitinib 37.5 mg. Four partial responses were seen. Stable disease >6 months was noted in an additional six patients.

CONCLUSION

Bortezomib and sunitinib are well tolerated and have anticancer activity, particularly in thyroid cancer. A phase 2 study of this combination in thyroid cancer patients is planned.