Takakuni Kato

Prognostic significance of epidermal growth factor receptor phosphorylation and mutation in head and neck squamous cell carcinoma.

The molecular status of the epidermal growth factor receptor (EGFR) has not been as well studied in head and neck squamous cell carcinoma (HNSCC) as in lung cancer. We examined the frequencies of EGFR mutations as well as the expression/phosphorylation status of the EGFR protein in HNSCC patients. Moreover, we tried to elucidate associations between EGFR molecular status and patient characteristics and disease-free survival. In this prospective cohort study, clinical data and samples were obtained from 82 consecutive patients who had not been treated with EGFR molecular targeting therapy. Full-length EGFR was sequenced, and expression and phosphorylation of the EGFR protein were measured by Western blotting. Four novel mutations (E709K, V765G, Ins770G, and G1022S) and one mutation well-known in lung cancer (L858R) were identified in six HNSCC samples (7%), but we could not find any mutations in the extracellular domain of EGFR, such as EGFRvIII, in this study. E709K and Ins770G as well as L858R appear to be functional mutations based on the use of Ba/F3 cells. In terms of patient characteristics, the number of metastatic lymph nodes and node stage were associated with phosphorylation of EGFR. No patients with EGFR mutations relapsed during the study period. Excluding mutated cases, patients whose tumor samples showed phosphorylated EGFR relapsed significantly earlier than those without phosphorylated EGFR. This finding was still significant after adjusting for mutation and overexpression of EGFR protein using the Cox proportional hazard model. In conclusion, phosphorylated EGFR without mutations may be a marker of poor prognosis in patients with HNSCC.

Copy number amplification of the PIK3CA gene is associated with poor prognosis in non-lymph node metastatic head and neck squamous cell carcinoma.

BackgroundDeregulation of the EGFR signaling pathway is one of the most frequently observed genetic abnormalities that drives cancer development. Although mutations in the downstream components of the EGFR signaling pathway, including KRAS, BRAF and PIK3CA, have been reported in numerous cancers, extensive mutation and copy number analysis of these genes in clinical samples has not been performed for head and neck squamous cell carcinoma (HNSCC).MethodsWe examined the mutations and copy number alterations of KRAS, BRAF and PIK3CA in 115 clinical specimens of HNSCC obtained from surgically treated patients.We used DNA sequencing to detect mutations and the copy number changes were evaluated by qPCR and array comparative genomic hybridization (CGH) analysis.ResultsWe examined the mutations and copy number alterations of KRAS, BRAF and PIK3CA in 115 clinical specimens of HNSCC obtained from surgically treated patients. We identified 3 mutations (2.6%) in K-RAS and 3 mutations (2.6%) in PIK3CA. Copy number amplification was found in 37 cases (32.2%) for PIK3CA, 10 cases (8.7%) for K-RAS and 2 cases (1.7%) for BRAF. Kaplan-Meier survival analysis revealed that copy-number amplification of PIK3CA was markedly associated with cancer relapse in patients without lymph node metastasis. (Log-rank test, p = 0.026)ConclusionsCopy number amplification of the PIK3CA gene is associated with poor prognosis in HNSCC patients without lymph node metastasis. The PIK3CA copy number status will serve as a marker of poor prognosis in patients with HNSCC.

Diagnostic utility of narrow-band imaging endoscopy for pharyngeal superficial carcinoma.

AIM To investigate the endoscopic features of pharyngeal superficial carcinoma and evaluate the utility of narrow-band imaging (NBI) for this disease. METHODS In the present prospective study, 335 patients underwent conventional white light (CWL) endoscopy and non-magnified/magnified NBI endoscopy, followed by an endoscopic biopsy, for 445 superficial lesions in the oropharynx and hypopharynx. The macroscopic appearance of superficial lesions was categorized as either elevated (< 5 mm in height), flat, or depressed (not ulcerous). Superficial carcinoma (SC) was defined as a superficial lesion showing high-grade dysplasia or squamous cell carcinoma on histology. The color, delineation, and macroscopic appearances of the lesions were evaluated by CWL endoscopy. The ratio of the brownish area/intervascular brownish epithelium (IBE), as well as microvascular proliferation, dilation, and irregularities, was determined by non-magnified/magnified NBI endoscopy. An experienced pathologist who was unaware of the endoscopic findings made the histological diagnoses. By comparing endoscopic findings with histology, we determined the endoscopic features of SC and evaluated the diagnostic utility of NBI. RESULTS The 445 lesions were divided histologically into two groups: a non-SC group, including non-neoplasia and low-grade dysplasia cases, and an SC group. Of the 445 lesions examined, 333 were classified as non-SC and 112 were classified as SC. There were no significant differences in age, gender, or the location of the lesions between the patients in the two groups. The mean diameter of the SC lesions was significantly greater than that of non-SC lesions (11.0 ± 7.6 mm vs 4.6 ± 3.6 mm, respectively, P < 0.001). Comparisons of CWL endoscopy findings for SC and non-SC lesions by univariate analysis revealed that the incidence of redness (72% vs 41%, respectively, P < 0.001) and a flat or depressed type of lesion (58% vs 44%, respectively, P = 0.013) was significantly higher in the SC group. Using non-magnified NBI endoscopy, the incidence of a brownish area was significantly higher for SC lesions (79% vs 57%, respectively, P < 0.001). On magnified NBI endoscopy, the incidence of IBE (68% vs 33%, P < 0.001) and microvascular proliferation (82% vs 51%, P < 0.001), dilation (90% vs 76%, P = 0.002), and irregularity (82% vs 31%, P < 0.001) was also significantly higher for the SC compared with the non-SC lesions. Multivariate analysis revealed that the incidence of redness (P = 0.022) on CWL endoscopy and IBE (P < 0.001) and microvascular irregularities (P < 0.001) on magnified NBI endoscopy was significantly higher in SC than non-SC lesions. Redness alone exhibited significantly higher sensitivity and significantly lower specificity for the diagnosis of SC compared with redness plus IBE and microvascular irregularities (72% vs 52%, P = 0.002; and 59% vs 92%, P < 0.001, respectively). The accuracy of redness plus IBE and irregularities for the diagnosis of SC was significantly greater than using redness alone (82% vs 62%, respectively, P < 0.001). CONCLUSION Redness, IBE, and microvascular irregularities appear to be closely related to SC lesions. Magnified NBI endoscopy may increase the diagnostic accuracy of CWL endoscopy for SC.

Distinct effects of alcohol consumption and smoking on genetic alterations in head and neck carcinoma.

Background Tobacco and alcohol consumption are risk factors for head and neck squamous cell carcinoma (HNSCC). Recently, whole-exome sequencing clarified that smoking increased TP53 and other mutations in HNSCC; however, the effects of alcohol consumption on these genetic alterations remain unknown. We explored the association between alcohol consumption and somatic copy-number alterations (SCNAs) across the whole genome in human papillomavirus (HPV)-negative HNSCCs, and compared with the effects of smoking on genetic alterations. Methods SCNA and TP53 mutations in tumor samples were examined by high-resolution comparative genomic hybridization microarray 180K and by direct sequencing, respectively, and statistically analyzed for associations with alcohol consumption and smoking during the 20 years preceding diagnosis of HNSCC. Probes with a corrected p-value (=q-value) less than 0.05 and fold change greater than 1.2 or less than -1.2 were considered statistically significant. Results A total of 248 patients with HNSCC were enrolled. In the HPV-negative patients (n=221), heavy alcohol consumption was significantly associated with SCNAs of oncogenes/oncosuppressors that were previously reported to occur frequently in HNSCCs: CDKN2A (q=0.005), FHIT (q=0.005), 11q13 region including CCND1, FADD and CTTN (q=0.005), ERBB2 (HER2) (q=0.009), 3q25-qter including CCNL1, TP63, DCUN1D1 and PIK3CA (q=0.014), and CSMD1 (q=0.019). But, TP53 mutations were not affected. In contrast, smoking was associated with increased risk of TP53 mutations, but did not induce any significant SCNAs of oncogenes/oncosuppressors. Conclusion These results suggest that both alcohol consumption and smoking had distinct effects on genetic alterations in HNSCCs. Heavy alcohol consumption may trigger previously known and unknown SCNAs, but may not induce TP53 mutation. In contrast, smoking may induce TP53 mutation, but may not trigger any SCNAs.

Prognostic Significance of Vitamin D Receptor Polymorphisms in Head and Neck Squamous Cell Carcinoma

Background In patients with advanced non-small-cell lung cancer, vitamin D receptor (VDR) polymorphisms and haplotypes are reported to be associated with survival. We hypothesized that a similar association would be observed in patients with head and neck squamous-cell carcinoma (HNSCC). Methods In a post-hoc analysis of our previous prospective cohort study, VDR polymorphisms including Cdx2 G/A (rs11568820), FokI C/T (rs10735810), BsmI A/G (rs1544410), ApaI G/T (rs7976091), and TaqI T/C (rs731236) were genotyped by sequencing in 204 consecutive patients with HNSCC who underwent tumor resection. Progression-free survival was compared between VDR polymorphisms using Kaplan-Meier survival curves with log-rank tests and Cox proportional hazard models adjusting for age, gender, smoking status, primary tumor sites, postoperative stages, existence of residual tumor, and postoperative treatment with chemotherapy or radiotherapy. Results During a median follow-up of 1,047 days, tumor progression and death occurred in 76 (37.3%) and 27 (13.2%) patients, respectively. The FokI T/T genotype was associated with poor progression-free survival: median survival for T/T was 265 days compared with 1,127 days for C/C or C/T (log-rank test: P = 0.0004; adjusted hazard ratio, 3.03; 95% confidence interval, 1.62 to 5.67; P = 0.001). In contrast, the other polymorphisms (Cdx2, BsmI, ApaI, TaqI) showed no significant association with progression-free survival. The A-T-G (Cdx2-FokI-ApaI) haplotype demonstrated a significant association with a higher progression rate (P = 0.02). Conclusion These results suggest that VDR polymorphisms and haplotypes may be associated with prognosis in patients with HNSCC, although the sample size is not large enough to draw definitive conclusions.

Functional mutation analysis of EGFR family genes and corresponding lymph node metastases in head and neck squamous cell carcinoma

Tumors with certain mutations in the epidermal growth factor receptor (EGFR) family genes dramatically respond to EGFR inhibitors. Therefore, these mutations are important factors that influence disease progression and patient survival. We previously studied the mutation status of EGFR in patients with head and neck squamous cell carcinoma (HNSCC). However, the mutation status of lymph node metastases and the frequency of mutations in EGFR family genes have not been extensively studied. In this study, we sequenced the catalytic domains of the three other members of the EGFR family, HER2, HER3, and HER4 in 92 clinical samples of HNSCC. We identified a HER2 mutation (K716E) in one sample but no mutations were found in HER3 or HER4. Next to investigate the relationship between EGFR mutations and tumor metastasis, we compared the DNA sequences of the EGFR gene between the primary tumor and the lymph node metastasis in 31 clinical samples. Only one of the patients with an EGFR mutation in the primary HNSCC carried the same mutation (L858R) in the lymph node metastasis. Finally, we explored the tumorigenic potential of the EGFR mutations that we had previously identified and their sensitivity to two different EGFR tyrosine kinase inhibitors (CL-387785, OSI-420). Ba/F3 cells transformed with mutant EGFR genes were sensitive to treatment with lower concentrations of CL-387785 than of OSI-420. These results contribute to our understanding of the genetic basis of drug sensitivity and will help design drugs that specifically target different subtypes of HNSCC.

Matched-pair analysis in patients with advanced oropharyngeal cancer: surgery versus concurrent chemoradiotherapy.

Objective: The current study aimed to compare the therapeutic outcomes of surgery with those of chemoradiation for patients with advanced oropharyngeal cancer (OPC). Methods: The data for 523 patients with previously untreated OPC were obtained from 12 institutions belonging to the Head and Neck Cancer Study Group in the Japan Clinical Oncology Group from April 2005 to March 2007. In this study, we matched a group of patients who underwent surgery with a second group treated with chemoradiation according to age, gender, subsite, and T and N classification, and analyzed the overall survival, progression-free survival, local control and swallowing function. Results: The final matched-pair analysis included 186 patients. The 5-year overall survival, progression-free survival and local control rates were 69.8 and 71.4% (p = 0.762), 51.0 and 54.4% (p = 0.531), and 75.2 and 80.3% (p = 0.399), respectively, in patients treated with surgery and those treated with chemoradiation. Swallowing function in patients treated with chemoradiation was significantly better than that in patients treated with surgery (p = 0.015). Conclusion: Although this study was not randomized, this matched-pair analysis of patients treated with surgery or chemoradiation showed that chemoradiation is as effective as surgery in the treatment of OPC.

Multidisciplinary therapy including proton beam radiotherapy for a Ewing sarcoma family tumor of maxillary sinus in a 4-year-old girl

Although complete resection offers the best chance for controlling head and neck Ewing sarcoma family tumors (ESFTs), it is occasionally unfeasible because of possible functional and cosmetic side effects. Planning multidisciplinary treatment for head and neck ESFT is challenging.

Craniofacial resection for malignant nasal and paranasal sinus tumors assisted with the endoscope

BACKGROUND Craniofacial resection is regarded as the treatment of choice for paranasal malignant tumors invading the skull base. Even with this approach, the surgical view remains obscured when tumors in the deep nasal and paranasal sinuses are resected. Endoscopy provides a wide and clear surgical view in the deep and narrow nasal cavity. We report two patients who underwent craniofacial resection assisted with endoscope. METHODS Two patients with malignant paranasal sinus tumor invading the anterior skull base underwent endoscope-assisted craniofacial resection. RESULTS To avoid a limited surgical view in the sinonasal cavity, we performed craniofacial resection with endoscopic osteotomy and several procedures in the nasal cavity. The neurosurgeon performed anterior skull base osteotomy at an appropriate site from above, while the otolaryngologist provided illumination with the endoscope from below and preserved the adjacent structures. The patients recovered uneventfully and the endoscopic examinations of both patients 18 months after the surgery showed no recurrence. CONCLUSIONS Endoscopes were useful for the craniofacial resection at osteotomy, providing illumination from below and at the several procedures in the deep part of the nasal cavity. If a lateral rhinotomy incision is made, the combined transfacial and transnasal approaches avoid the limited working angle associated with the transnasal approach alone. Although an endoscopic approach is useful for treating sinonasal tumors, we should recognize its advantages and limitations.

The role of initial neck dissection for patients with node-positive oropharyngeal squamous cell carcinomas.

BACKGROUND The current study sought to assess the role of initial neck dissection (ND) for patients with node-positive oropharyngeal squamous cell carcinomas (OPSCC). METHODS The data for 202 patients with previously untreated node-positive OPSCC were gathered from 12 institutions belonging to the Head and Neck Cancer Study Group in the Japan Clinical Oncology Group. These patients were categorized into two groups, consisting of the initial ND group and the wait-and-see group, according to treatment policy. RESULTS Regional recurrence was observed in 17 of 93 patients undergoing initial ND, whereas, recurrent or persistent diseases were observed in 40 of 109 patients who did not undergo initial ND. The 4-year overall survival rates (OS) for the wait-and-see group and initial ND groups were 74.0% and 78.7%, respectively, and the 4-year regional control rates (RC) for each group were 77.6% and 84.9%. There were no significant differences in either OS or RC (p=0.3440 and p=0.2382, respectively). However, for patients with N3 disease, the 4-year OS of the initial ND group (100%) was favorable. For patients with N2a disease, the 4-year RC of the initial ND group was higher than that of the wait-and-see group statistically (100% vs 62.5%, p=0.0156). CONCLUSIONS The role of initial ND was limited in patients with node-positive OPSCC. The treatment strategy not involving initial ND is considered feasible and acceptable when nodal evaluation after definitive radiotherapy or chemoradiotherapy is applied adequately. However, it is possible that initial ND improves outcomes in patients with resectable large-volume nodal disease.