Hyunseok Kang

Antitumor Activity of Pembrolizumab in Biomarker-Unselected Patients With Recurrent and/or Metastatic Head and Neck Squamous Cell Carcinoma: Results From the Phase Ib KEYNOTE-012 Expansion Cohort

Purpose Treatment with pembrolizumab, an anti–programmed death-1 antibody, at 10 mg/kg administered once every 2 weeks, displayed durable antitumor activity in programmed death-ligand 1 (PD-L1) –positive recurrent and/or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) in the KEYNOTE-012 trial. Results from the expansion cohort, in which patients with HNSCC, irrespective of biomarker status, received a fixed dose of pembrolizumab at a less frequent dosing schedule, are reported. Patients and Methods Patients with R/M HNSCC, irrespective of PD-L1 or human papillomavirus status, received pembrolizumab 200 mg intravenously once every 3 weeks. Imaging was performed every 8 weeks. Primary end points were overall response rate (ORR) per central imaging vendor (Response Evaluation Criteria in Solid Tumors v1.1) and safety. Secondary end points included progression-free survival, overall survival, and association of response and PD-L1 expression. Patients who received one or more doses of pembrolizumab were included in analyses. Results Of 132 patients enrolled, median age was 60 years (range, 25 to 84 years), 83% were male, and 57% received two or more lines of therapy for R/M disease. ORR was 18% (95% CI, 12 to 26) by central imaging vendor and 20% (95% CI, 13 to 28) by investigator review. Median duration of response was not reached (range, ≥ 2 to ≥ 11 months). Six-month progression-free survival and overall survival rates were 23% and 59%, respectively. By using tumor and immune cells, a statistically significant increase in ORR was observed for PD-L1–positive versus –negative patients (22% v 4%; P = .021). Treatment-related adverse events of any grade and grade ≥ 3 events occurred in 62% and 9% of patients, respectively. Conclusion Fixed-dose pembrolizumab 200 mg administered once every 3 weeks was well tolerated and yielded a clinically meaningful ORR with evidence of durable responses, which supports further development of this regimen in patients with advanced HNSCC.

Evolution of Neoantigen Landscape during Immune Checkpoint Blockade in Non–Small Cell Lung Cancer

Immune checkpoint inhibitors have shown significant therapeutic responses against tumors containing increased mutation-associated neoantigen load. We have examined the evolving landscape of tumor neoantigens during the emergence of acquired resistance in patients with non-small cell lung cancer after initial response to immune checkpoint blockade with anti-PD-1 or anti-PD-1/anti-CTLA-4 antibodies. Analyses of matched pretreatment and resistant tumors identified genomic changes resulting in loss of 7 to 18 putative mutation-associated neoantigens in resistant clones. Peptides generated from the eliminated neoantigens elicited clonal T-cell expansion in autologous T-cell cultures, suggesting that they generated functional immune responses. Neoantigen loss occurred through elimination of tumor subclones or through deletion of chromosomal regions containing truncal alterations, and was associated with changes in T-cell receptor clonality. These analyses provide insight into the dynamics of mutational landscapes during immune checkpoint blockade and have implications for the development of immune therapies that target tumor neoantigens.Significance: Acquired resistance to immune checkpoint therapy is being recognized more commonly. This work demonstrates for the first time that acquired resistance to immune checkpoint blockade can arise in association with the evolving landscape of mutations, some of which encode tumor neoantigens recognizable by T cells. These observations imply that widening the breadth of neoantigen reactivity may mitigate the development of acquired resistance. Cancer Discov; 7(3); 264-76. ©2017 AACR.See related commentary by Yang, p. 250This article is highlighted in the In This Issue feature, p. 235.

Detection of somatic mutations and HPV in the saliva and plasma of patients with head and neck squamous cell carcinomas

Tumor DNA in saliva and plasma can provide a noninvasive biomarker for head and neck squamous cell carcinoma. A cancer test that’s worth a spit Head and neck squamous cell carcinoma is one of the most common cancers worldwide, and its incidence is increasing. This is a difficult-to-treat cancer for which few targeted agents are available, and there are no biomarkers for monitoring therapeutic progress. Wang et al. discovered that tumor DNA can be detected and analyzed in the blood of most patients with head and neck cancers, as well as in the saliva of those with cancers of the oral cavity. Moreover, they found preliminary evidence suggesting that tumor DNA may be detectable in saliva before clinical evidence of tumor recurrence, which may be useful for patient monitoring if this result is confirmed in larger studies. To explore the potential of tumor-specific DNA as a biomarker for head and neck squamous cell carcinomas (HNSCC), we queried DNA from saliva or plasma of 93 HNSCC patients. We searched for somatic mutations or human papillomavirus genes, collectively referred to as tumor DNA. When both plasma and saliva were tested, tumor DNA was detected in 96% of 47 patients. The fractions of patients with detectable tumor DNA in early- and late-stage disease were 100% (n = 10) and 95% (n = 37), respectively. When segregated by site, tumor DNA was detected in 100% (n = 15), 91% (n = 22), 100% (n = 7), and 100% (n = 3) of patients with tumors of the oral cavity, oropharynx, larynx, and hypopharynx, respectively. In saliva, tumor DNA was found in 100% of patients with oral cavity cancers and in 47 to 70% of patients with cancers of the other sites. In plasma, tumor DNA was found in 80% of patients with oral cavity cancers, and in 86 to 100% of patients with cancers of the other sites. Thus, saliva is preferentially enriched for tumor DNA from the oral cavity, whereas plasma is preferentially enriched for tumor DNA from the other sites. Tumor DNA in saliva was found postsurgically in three patients before clinical diagnosis of recurrence, but in none of the five patients without recurrence. Tumor DNA in the saliva and plasma appears to be a potentially valuable biomarker for detection of HNSCC.

Emerging biomarkers in head and neck cancer in the era of genomics

Head and neck cancer (HNC) broadly includes carcinomas arising from the mucosal epithelia of the head and neck region as well as various cell types of salivary glands and the thyroid. As reflected by the multiple sites and histologies of HNC, the molecular characteristics and clinical outcomes of this disease vary widely. In this Review, we focus on established and emerging biomarkers that are most relevant to nasopharyngeal carcinoma and head and neck squamous-cell carcinoma (HNSCC), which includes primary sites in the oral cavity, oropharynx, hypopharynx and larynx. Applications and limitations of currently established biomarkers are discussed along with examples of successful biomarker development. For emerging biomarkers, preclinical or retrospective data are also described in the context of recently completed comprehensive molecular analyses of HNSCC, which provide a broad genetic landscape and molecular classification beyond histology and clinical characteristics. We will highlight the ongoing effort that will see a shift from prognostic to predictive biomarker development in HNC with the goal of delivering individualized cancer therapy.

Pembrolizumab for platinum- and cetuximab-refractory head and neck cancer: Results from a single-arm, phase II study

Purpose There are no approved treatments for recurrent/metastatic head and neck squamous cell carcinoma refractory to platinum and cetuximab. In the single-arm, phase II KEYNOTE-055 study, we evaluated pembrolizumab, an anti-programmed death 1 receptor antibody, in this platinum- and cetuximab-pretreated population with poor prognosis. Methods Eligibility stipulated disease progression within 6 months of platinum and cetuximab treatment. Patients received pembrolizumab 200 mg every 3 weeks. Imaging was performed every 6 to 9 weeks. Primary end points: overall response rate (Response Evaluation Criteria in Solid Tumors v1.1, central review) and safety. Efficacy was assessed in all dosed patients and in subgroups on the basis of programmed death ligand 1 (PD-L1) expression and human papillomavirus (HPV) status. Results Among 171 patients treated, 75% received two or more prior lines of therapy for metastatic disease, 82% were PD-L1 positive, and 22% were HPV positive. At the time of analysis, 109 patients (64%) experienced a treatment-related adverse event; 26 patients (15%) experienced a grade ≥ 3 event. Seven patients (4%) discontinued treatment, and one died of treatment-related adverse events. Overall response rate was 16% (95% CI, 11% to 23%), with a median duration of response of 8 months (range, 2+ to 12+ months); 75% of responses were ongoing at the time of analysis. Response rates were similar in all HPV and PD-L1 subgroups. Median progression-free survival was 2.1 months, and median overall survival was 8 months. Conclusion Pembrolizumab exhibited clinically meaningful antitumor activity and an acceptable safety profile in recurrent/metastatic head and neck squamous cell carcinoma previously treated with platinum and cetuximab.

Genomic alterations in head and neck squamous cell carcinoma determined by cancer gene-targeted sequencing

BACKGROUND To determine genomic alterations in head and neck squamous cell carcinoma (HNSCC) using formalin-fixed, paraffin-embedded (FFPE) tumors obtained through routine clinical practice, selected cancer-related genes were evaluated and compared with alterations seen in frozen tumors obtained through research studies. PATIENTS AND METHODS DNA samples obtained from 252 FFPE HNSCC were analyzed using next-generation sequencing-based (NGS) clinical assay to determine sequence and copy number variations in 236 cancer-related genes plus 47 introns from 19 genes frequently rearranged in cancer. Human papillomavirus (HPV) status was determined by presence of the HPV DNA sequence in all samples and corroborated with high-risk HPV in situ hybridization (ISH) and p16 immunohistochemical (IHC) staining in a subset of tumors. Sequencing data from 399 frozen tumors in The Cancer Genome Atlas and University of Chicago public datasets were analyzed for comparison. RESULTS Among 252 FFPE HNSCC, 84 (33%) were HPV positive and 168 (67%) were HPV negative by sequencing. A subset of 40 tumors with HPV ISH and p16 IHC results showed complete concordance with NGS-derived HPV status. The most common genes with genomic alterations were PIK3CA and PTEN in HPV-positive tumors and TP53 and CDKN2A/B in HPV-negative tumors. In the pathway analysis, the PI3K pathway in HPV-positive tumors and DNA repair-p53 and cell cycle pathways in HPV-negative tumors were frequently altered. The HPV-positive oropharynx and HPV-positive nasal cavity/paranasal sinus carcinoma shared similar mutational profiles. CONCLUSION The genomic profile of FFPE HNSCC tumors obtained through routine clinical practice is comparable with frozen tumors studied in research setting, demonstrating the feasibility of comprehensive genomic profiling in a clinical setting. However, the clinical significance of these genomic alterations requires further investigation through application of these genomic profiles as integral biomarkers in clinical trials.BACKGROUND To determine genomic alterations in head and neck squamous cell carcinoma (HNSCC) using formalin-fixed, paraffin-embedded (FFPE) tumors obtained through routine clinical practice, selected cancer-related genes were evaluated and compared with alterations seen in frozen tumors obtained through research studies. PATIENTS AND METHODS DNA samples obtained from 252 FFPE HNSCC were analyzed using next-generation sequencing-based (NGS) clinical assay to determine sequence and copy number variations in 236 cancer-related genes plus 47 introns from 19 genes frequently rearranged in cancer. Human papillomavirus (HPV) status was determined by presence of the HPV DNA sequence in all samples and corroborated with high-risk HPV in situ hybridization (ISH) and p16 immunohistochemical (IHC) staining in a subset of tumors. Sequencing data from 399 frozen tumors in The Cancer Genome Atlas and University of Chicago public datasets were analyzed for comparison. RESULTS Among 252 FFPE HNSCC, 84 (33%) were HPV positive and 168 (67%) were HPV negative by sequencing. A subset of 40 tumors with HPV ISH and p16 IHC results showed complete concordance with NGS-derived HPV status. The most common genes with genomic alterations were PIK3CA and PTEN in HPV-positive tumors and TP53 and CDKN2A/B in HPV-negative tumors. In the pathway analysis, the PI3K pathway in HPV-positive tumors and DNA repair-p53 and cell cycle pathways in HPV-negative tumors were frequently altered. The HPV-positive oropharynx and HPV-positive nasal cavity/paranasal sinus carcinoma shared similar mutational profiles. CONCLUSION The genomic profile of FFPE HNSCC tumors obtained through routine clinical practice is comparable with frozen tumors studied in research setting, demonstrating the feasibility of comprehensive genomic profiling in a clinical setting. However, the clinical significance of these genomic alterations requires further investigation through application of these genomic profiles as integral biomarkers in clinical trials.

Head and Neck PET/CT: Therapy Response Interpretation Criteria (Hopkins Criteria)—Interreader Reliability, Accuracy, and Survival Outcomes

There has been no established qualitative system of interpretation for therapy response assessment using PET/CT for head and neck cancers. The objective of this study was to validate the Hopkins interpretation system to assess therapy response and survival outcome in head and neck squamous cell cancer patients (HNSCC). Methods: The study included 214 biopsy-proven HNSCC patients who underwent a posttherapy PET/CT study, between 5 and 24 wk after completion of treatment. The median follow-up was 27 mo. PET/CT studies were interpreted by 3 nuclear medicine physicians, independently. The studies were scored using a qualitative 5-point scale, for the primary tumor, for the right and left neck, and for overall assessment. Scores 1, 2, and 3 were considered negative for tumors, and scores 4 and 5 were considered positive for tumors. The Cohen κ coefficient (κ) was calculated to measure interreader agreement. Overall survival (OS) and progression-free survival (PFS) were analyzed by Kaplan–Meier plots with a Mantel–Cox log-rank test and Gehan Breslow Wilcoxon test for comparisons. Results: Of the 214 patients, 175 were men and 39 were women. There was 85.98%, 95.33%, 93.46%, and 87.38% agreement between the readers for overall, left neck, right neck, and primary tumor site response scores, respectively. The corresponding κ coefficients for interreader agreement between readers were, 0.69–0.79, 0.68–0.83, 0.69–0.87, and 0.79–0.86 for overall, left neck, right neck, and primary tumor site response, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of the therapy assessment were 68.1%, 92.2%, 71.1%, 91.1%, and 86.9%, respectively. Cox multivariate regression analysis showed human papillomavirus (HPV) status and PET/CT interpretation were the only factors associated with PFS and OS. Among the HPV-positive patients (n = 123), there was a significant difference in PFS (hazard ratio [HR], 0.14; 95% confidence interval, 0.03–0.57; P = 0.0063) and OS (HR, 0.01; 95% confidence interval, 0.00–0.13; P = 0.0006) between the patients who had a score negative for residual tumor versus positive for residual tumor. A similar significant difference was observed in PFS and OS for all patients. There was also a significant difference in the PFS of patients with PET-avid residual disease in one site versus multiple sites in the neck (HR, 0.23; log-rank P = 0.004). Conclusion: The Hopkins 5-point qualitative therapy response interpretation criteria for head and neck PET/CT has substantial interreader agreement and excellent negative predictive value and predicts OS and PFS in patients with HPV-positive HNSCC.

Class I HDACs are mediators of smoke carcinogen-induced stabilization of DNMT1 and serve as promising targets for chemoprevention of lung cancer.

DNA methylation is an early event in bronchial carcinogenesis and increased DNA methyltransferase (DNMT)1 protein expression is a crucial step in the oncogenic transformation of epithelia. Here, we investigate the role of class I histone deacetylases (HDAC) 1 to 3 in the stabilization of DNMT1 protein and as a potential therapeutic target for lung cancer chemoprevention. Long-term exposure of immortalized bronchial epithelial cells (HBEC-3KT) to low doses of tobacco-related carcinogens led to oncogenic transformation, increased HDAC expression, cell-cycle independent increased DNMT1 stability, and DNA hypermethylation. Overexpression of HDACs was associated with increased DNMT1 stability and knockdown of HDACs reduced DNMT1 protein levels and induced DNMT1 acetylation. This suggests a causal relationship among increased class I HDACs levels, upregulation of DNMT1 protein, and subsequent promoter hypermethylation. Targeting of class I HDACs with valproic acid (VPA) was associated with reduced HDAC expression and a profound reduction of DNMT1 protein level. Treatment of transformed bronchial epithelial cells with VPA resulted in reduced colony formation, demethylation of the aberrantly methylated SFRP2 promoter, and derepression of SFRP2 transcription. These data suggest that inhibition of HDAC activity may reverse or prevent carcinogen-induced transformation. Finally, immunohistochemistry on human lung cancer specimens revealed a significant increase in DNMT1, HDAC1, HDAC2, and HDAC3 expression, supporting our hypotheses that class I HDACs are mediators of DNMT1 stability. In summary, our study provides evidence for an important role of class I HDACs in controlling the stability of DNMT1 and suggests that HDAC inhibition could be an attractive approach for lung cancer chemoprevention. Cancer Prev Res; 7(3); 351–61. ©2014 AACR.

Differences in the Prevalence of Human Papillomavirus (HPV) in Head and Neck Squamous Cell Cancers by Sex, Race, Anatomic Tumor Site, and HPV Detection Method

Importance Human papillomavirus (HPV) causes an increasing proportion of oropharyngeal squamous cell carcinomas (OPSCCs), particularly in white men. The prevalence of HPV among other demographic groups and other anatomic sites of HNSCC is unclear. Objective To explore the role of HPV tumor status among women and nonwhites with OPSCC and patients with nonoropharyngeal head and neck squamous cell carcinoma (non-OP HNSCC). Design, Setting, and Participants Retrospective cohort study at 2 tertiary academic centers including cases diagnosed 1995 through 2012, oversampled for minorities and females. A stratified random sample of 863 patients with newly diagnosed SCC of the oral cavity, oropharynx, larynx, or nasopharynx was used. Main Outcomes and Measures Outcomes were HPV status as measured by p16 immunohistochemical analysis, HPV16 DNA in situ hybridization (ISH), and high-risk HPV E6/E7 mRNA ISH. Results Of 863 patients, 551 (63.9%) were male and median age was 58 years (interquartile range, 51-68 years). Among 240 OPSCCs, 144 (60%) were p16 positive (p16+), 115 (48%) were HPV16 DNA ISH positive (ISH16+), and 134 (56%) were positive for any oncogenic HPV type (ISH+). From 1995 to 2012, the proportion of p16+ OPSCC increased significantly among women (from 29% to 77%; P = .005 for trend) and men (36% to 72%; P < .001 for trend), as well as among whites (39% to 86%; P < .001 for trend) and nonwhites (32% to 62%; P = .02 for trend). Similar results were observed for ISH+ OPSCC (P ⩽ .01 for all). Among 623 non-OP HNSCCs, a higher proportion were p16+ compared with ISH positive (62 [10%] vs 30 [5%]; P = .001). A high proportion (26 of 62 [42%]) of these p16+ non-OP HNSCCs were found in sites adjacent to the oropharynx. The proportion of p16+ and ISH+ non-OP HNSCCs were similar by sex. Over time, the proportion of non-OP HNSCCs that were p16+ (or ISH+) increased among whites (P = .04 for trend) but not among nonwhites (each P > .51 for trend). Among OPSCCs, p16 had high sensitivity (100%), specificity (91%), and positive (93%) and negative predictive value (100%) for ISH positivity. In non-OP HNSCCs, p16 had lower sensitivity (83%) and positive predictive value (40%) but high specificity (94%) and negative predictive value (99%) for ISH positivity. Conclusions and Relevance During 1995 through 2012, the proportion of OPSCCs caused by HPV has increased significantly. This increase was not restricted to white men but was a consistent trend for women and men, as well as for white and nonwhite racial groups. Few non-OP HNSCCs were HPV related. P16 positivity was a good surrogate for ISH+ tumor status among OPSCC, but not a good surrogate for non-OP HNSCC.

Resumption or persistence of menstruation after cytotoxic chemotherapy is a prognostic factor for poor disease-free survival in premenopausal patients with early breast cancer

BACKGROUND We investigated the relationship between resumption or persistence of menstruation after cytotoxic chemotherapy (RM) and disease-free survival (DFS) in premenopausal patients with early breast cancer. METHODS Medical records from 872 patients who received cytotoxic chemotherapy for stage I to III breast cancer were retrospectively reviewed. RESULTS The median patient age was 41 years (range, 21-54) and the median follow-up duration was 6.2 years (range, 0.7-10.4). Six hundred ninety-two patients (79.4%) were hormone receptor (HR) positive and the majority of these received tamoxifen therapy after completing chemotherapy. The chemotherapy-induced amenorrhea (CIA) rate was 76.7% (n=669), and 51.8% (n=452) experienced RM during the follow-up period. One hundred twenty-one (13.9%) patients had persistent menstruation without CIA. DFS was significantly affected by younger age at diagnosis (≤35 years) (P=0.013), tumor size>2 cm (P<0.001), node positivity (P<0.001), HR negativity (P<0.001), HER2 positivity (P=0.010), and RM (P<0.001). HR negativity [hazard ratio 1.7, 95% confidence interval (CI) 1.2-2.4, P=0.006], tumor size>2 cm (hazard ratio 2.1, 95% CI 1.4-3.0, P<0.001), node positivity (hazard ratio 3.0, 95% CI 2.0-4.7, P<0.001), and RM (hazard ratio 1.8, 95% CI 1.2-2.7, P=0.004) remained significant factors for DFS on multivariate analysis. CONCLUSIONS A considerable proportion of premenopausal patients treated with chemotherapy experienced RM after CIA. RM was a poor prognostic factor for DFS in premenopausal patients with early breast cancer.BACKGROUND We investigated the relationship between resumption or persistence of menstruation after cytotoxic chemotherapy (RM) and disease-free survival (DFS) in premenopausal patients with early breast cancer. METHODS Medical records from 872 patients who received cytotoxic chemotherapy for stage I to III breast cancer were retrospectively reviewed. RESULTS The median patient age was 41 years (range, 21-54) and the median follow-up duration was 6.2 years (range, 0.7-10.4). Six hundred ninety-two patients (79.4%) were hormone receptor (HR) positive and the majority of these received tamoxifen therapy after completing chemotherapy. The chemotherapy-induced amenorrhea (CIA) rate was 76.7% (n = 669), and 51.8% (n = 452) experienced RM during the follow-up period. One hundred twenty-one (13.9%) patients had persistent menstruation without CIA. DFS was significantly affected by younger age at diagnosis (≤35 years) (P = 0.013), tumor size > 2 cm (P < 0.001), node positivity (P < 0.001), HR negativity (P < 0.001), HER2 positivity (P = 0.010), and RM (P < 0.001). HR negativity [hazard ratio 1.7, 95% confidence interval (CI) 1.2-2.4, P = 0.006], tumor size > 2 cm (hazard ratio 2.1, 95% CI 1.4-3.0, P < 0.001), node positivity (hazard ratio 3.0, 95% CI 2.0-4.7, P < 0.001), and RM (hazard ratio 1.8, 95% CI 1.2-2.7, P = 0.004) remained significant factors for DFS on multivariate analysis. CONCLUSIONS A considerable proportion of premenopausal patients treated with chemotherapy experienced RM after CIA. RM was a poor prognostic factor for DFS in premenopausal patients with early breast cancer.