Diagnostic sensitivity of ¹8fluorodeoxyglucose positron emission tomography for detecting synchronous multiple primary cancers in head and neck cancer patients.

We assessed the sensitivity of positron emission tomography (PET) for detecting synchronous multiple primary cancers, particularly synchronous esophageal cancers in head and neck cancer patients. We retrospectively reviewed 230 head and neck cancer patients. All the patients routinely underwent the following examinations: urinalysis, occult blood, tumor marker detection [squamous cell carcinoma (SCC), cytokeratin fragment (CYFRA), and carcinoembryonic antigen (CEA)], esophagogastroduodenoscopy, colonoscopy (when CEA was high or occult blood was positive), abdominal ultrasonography, plain chest computed tomography (CT), and PET. Bronchoscopy was performed when CT revealed lung shadow of central region. Synchronous multiple primary cancers were detected in 42 (18.2%) patients. The diagnostic sensitivity of PET for synchronous primary cancers was as follows: esophagus, 7.6% (1/13); stomach, 25.0% (2/8); lung, 66.7% (4/6); head and neck, 75.0% (3/4); colon, 0% (0/1); kidney, 0% (0/1); and subcutaneous, 100% (1/1). The sensitivity of PET for detecting synchronous esophageal cancers is low because these are early-stage cancers (almost stage 0-I). Therefore, it is necessary to perform esophagogastroduodenoscopy for detecting synchronous esophageal cancers. PET is an important additional tool for detecting synchronous multiple primary cancers because the diagnostic sensitivity of PET in synchronous head and neck cancer and lung cancer is high. But PET has the limitation of sensitivity for synchronous multiple primary cancers because the diagnostic sensitivity of PET in synchronous esophageal cancer is very low.

Acoustic characteristics of ataxic speech in Japanese patients with spinocerebellar degeneration (SCD).

BACKGROUND: In English- and German-speaking countries, ataxic speech is often described as showing scanning based on acoustic impressions. Although the term 'scanning' is generally considered to represent abnormal speech features including prosodic excess or insufficiency, any precise acoustic analysis of ataxic speech has not been performed in Japanese-speaking patients. This raises the question of what is the most dominant acoustic characteristic of ataxic speech in Japanese subjects, particularly related to the perceptual impression of 'scanning'. AIMS: The study was designed to investigate the nature of speech characteristics of Japanese ataxic subjects, particularly 'scanning', by means of acoustic analysis. METHODS & PROCEDURES: The study comprised 20 Japanese cases with spinocerebellar degeneration diagnosed to have a perceptual impression of scanning by neurologists (ataxic group) and 20 age-matched normal healthy subjects (control group). Recordings of speech samples of Japanese test sentences were obtained from each subject. The recorded and digitized acoustic samples were analysed using 'Acoustic Core-8' (Arcadia Inc.). OUTCOMES & RESULTS: Sentence duration was significantly longer in the ataxic group as compared with the control group, indicating that the speaking rate was slower in the ataxic subjects. Segment duration remained consistent in both vowels and consonants in the control group as compared with the ataxic group. In particular, the duration of vowel segments, i.e. the nucleus of Japanese mora, was significantly invariable in the control group regardless of differences between subjects as well as in segments compared with the ataxic group. In addition, the duration of phonemically long Japanese vowels was significantly shorter in the ataxic group. CONCLUSIONS & IMPLICATIONS: The results indicate that the perceptual impression of 'scanning' in Japanese ataxic cases derives mainly from the breakdown of isochrony in terms of difficulty in keeping the length of vowel segments of Japanese invariable during speech production. In addition, the tendency toward irregular shortening of the length of phonemically long Japanese vowels is thought to reinforce the impression of 'scanning' in ataxic speech in Japanese cases.

Gene status of head and neck squamous cell carcinoma cell lines and cetuximab-mediated biological activities.

Cetuximab is a chimeric IgG1 monoclonal antibody that targets epidermal growth factor receptor (EGFR). Cetuximab binds to EGFR and prevents phosphorylation of EGFR. Moreover, preclinical results have shown the ability of cetuximab to induce either complement-mediated tumor cell killing (CDC) or antibody-dependent cell-mediated-cytotoxicity (ADCC). We previously reported mutation in EGFR regarding head and neck squamous cell carcinoma (HNSCC) cell lines. In the present study, we analyzed the same 16 HNSCC cell lines for mutations in KRAS, PIK3CA, BRAF and PTEN. Furthermore, we evaluated cetuximab-mediated biological activities (antiproliferative effect by the MTT assay and ADCC) regarding these cell lines. Mutations in PIK3CA and PTEN were observed in two cell lines (2/16, 12.5%), but no mutation was observed in KRAS and BRAF. The antiproliferative effect of cetuximab by the MTT assay was not strong, and no correlation was observed between the antiproliferative effect of cetuximab and mutations in EGFR, KRAS, PIK3CA, BRAF and PTEN in these cell lines. Therefore, the mutation status of EGFR and downstream molecules were not useful for predicting the antitumor effects of cetuximab on HNSCC. Cetuximab-mediated ADCC was observed in these cell lines and might have been influenced by the expression of EGFR. Therefore, cetuximab-mediated ADCC seems to be an important part of the antitumor mechanisms of cetuximab and the expression levels of EGFR might influence the antitumor activity of cetuximab. Therefore, besides the antiproliferative effect of cetuximab by the MTT assay, it appeared important to evaluate cetuximab-mediated ADCC as well as EGFR expression in HNSCC cells.

Phase I/II study of s-1 plus cisplatin combination chemotherapy in patients with advanced/recurrent head and neck cancer.

OBJECTIVE: The objectives of this study were to determine the maximum tolerated dose (MTD) and recommended dose (RD) of S-1 plus cisplatin (CDDP) and to evaluate safety and efficacy using the defined RD in advanced/recurrent head and neck cancer (HNC). METHODS: S-1 was administered orally at 40 mg/m(2) twice daily for 14 consecutive days, and CDDP was infused on day 8 at a dose of 60 and 70 mg/m(2). Each course was repeated every 4 weeks. RESULTS: A total of 38 patients were registered, 10 patients for the Phase I study and an additional 28 patients for the Phase II study. Although no dose-limiting toxicity (DLT) was observed in the CDDP 60 mg/m(2) (Level 1) group, two of six patients in the CDDP 70 mg/m(2) (Level 2) group exhibited DLT (fatigue/diarrhea). The MTD was not achieved in the Phase I study. Level 2 was therefore determined as the RD. In the Phase II study, 34 patients, including 6 patients from the Phase I study, were evaluated. At the termination of treatment, the confirmed response rate was 44.1% (15/34, 95% CI: 27.4-60.8). The best response rate without an adequate duration time was 67.6% (95% CI: 51.9-83.4). The median survival period was 16.7 months, and the 1-year survival rate was 60.1%. The main toxicities of Grade 3 or above were anorexia (26.5%), nausea (14.7%), neutropenia/thrombocytopenia (11.8%) and anemia/fatigue (8.8%). CONCLUSIONS: This is considered to be an effective regimen with acceptable toxicities for HNC.

Role of 18F-FDG PET in detecting primary site in the patient with primary unknown carcinoma.

The aim of this study was to verify the effectiveness of positron emission tomography (PET) in detecting primary sites in carcinoma of unknown primary (CUP) patients. In this study, CUP represented a group of heterogeneous tumors that shared the clinical manifestation of metastatic carcinoma with no obvious primary site at the time of first diagnosis, which included clinical investigations, computed tomography, magnetic resonance imaging and panendoscopy. We reviewed the records of 24 patients with CUP between January 1995 and December 2009. The patients who demonstrated additional tracer uptake sites other than previously known metastatic lesions by PET scan were done direct biopsies for the sites of accumulation. Patients who had a negative PET scan or for whom the primary site could not be identified by direct biopsies underwent examination under anesthesia of the at-risk occult tumor sites. PET scan demonstrated focal accumulation suspicious for primary tumor in 12 (50.0%) of 24 patients: tonsil 5, nasopharynx 3, hypopharynx 1, tongue 1, larynx 1, and maxillary sinus 1. A subsequent biopsy of these sites revealed primary cancer in 9 (37.5%) of 24 patients: tonsil 5, nasopharynx 1, hypopharynx 1, tongue 1, and maxillary sinus 1. In the remaining three patients, no malignant cells were found by the biopsy of the accumulated area: nasopharynx 2, larynx 1. PET scans increase the yield of primary tumor by 37.5%. The sensitivity, specificity for PET scan were 80.8, 76.9%, respectively. PET scanning is useful in detecting primary cancer of CUP patients.

Eosinophilic chronic rhinosinusitis in Japan.

Chronic rhinosinusitis is a heterogeneous disease. In Europe and the United States, it has recently been divided into two subgroups: chronic rhinosinusitis with nasal polyps (CRSwNP) and chronic rhinosinusitis without nasal polyps (CRSsNP). The majority of CRSwNP cases have a strong tendency to recur after surgery and show eosinophil-dominant inflammation. However, this definition has proved difficult to apply in Japan and East Asia, because more than half of the CRSwNP cases do not exhibit eosinophil-dominant inflammation in these areas of the world. In Japan in the 1990s, refractory CRSwNP to the standard treatment was focused on in clinical studies and the term "eosinophilic chronic rhinosinusitis" (ECRS) was introduced to identify this subgroup of chronic rhinosinusitis in 2001. ECRS is different from non-ECRS in terms of many clinical features: symptom appearance, occurrence site of nasal polyps, CT scan findings, the histology of nasal polyps, blood examination findings, clinical course after surgery, and co-morbid asthma, etc. In this review, we describe these clinical features and mention how to make a clinical diagnosis of ECRS as well as how to treat it. Finally, we discuss the pathophysiology of ECRS. The concept of ECRS in Japan would be applicable for CRSwNP in other countries including Europe and the United States.

[A case of thyroid crisis in acute tonsillitis treatment].

We report a case of fatal thyroid crisis induced by acute tonsillitis. A 33-year-old woman with untreated hyperthyroidism developed thyroid crisis during acute tonsillitis treatment. The four days passing from crisis onset to treatment initiation unduly compromised her condition, resulting in death. Such cases point up the need for prompt thyroid crisis diagnosis and treatment, the difference between a proactive life-sustaining response and a negative mortal result.

[Parotid gland cancer treatment with facial nerve preservation].

Based on clinical features in 34 cases of parotid gland cancer treated between January 1997 and December 2007, tumor, node, and metastasis classification found 5 subjects to be T1, 12 to be T2, 7 to be T3, and 10 to be T4a. Of these, 25 were staged for N0, 3 for N1, and 6 for N2. Histopathologically, 10 different tumor types were observed, with carci-noma ex pleomorphic adenoma the most common. Preoperative fine-needle aspiration cytology (FNAC) of parotid gland tumor was done on 126 and cytological findings compared to histopathologic diagnoses of surgically resected specimens. Sensitivity for malignancy was 76.0%, specificity 95.4%, and overall accuracy 91.1%. Six malignant tumors were diagnosed as benign and 4 benign as malignant by FNAC, indicating that FNAC results alone may not be sufficient for diagnosing malignancy definitively. Among subjects, 25 underwent surgical resection, with the facial nerve preserved in 15 of 29. Postoperative radiotherapy was indicated if lymph node metastasis, intermediate or high-grade malignancy, or positive margins were seen. Of 15 subjects undergoing postoperative radiotherapy, 3 experienced recurrence. For unresectable tumors, concurrent chemoradiotherapy was used for 3 subjects and 2 underwent radiotherapy alone, with all 5 current survivors. The 5-year overall survival (OS) was 87.4% and progression-free survival (PFS) 71.4%. In terms of 5-year PFS, significant differences were seen between stage I/II (91.7%) and stage III/IW (51.6%) (P=0.032), and between N0 (86.2%) and N+ (38.1%) (P=0.002).

[Study of cerebellar infarction with isolated vertigo].

Isolated vertigo is generally attributed to labyrinthine disease, but may also signal otherwise asymptomatic cerebellar infarction. Of 309 subjects admitted between April 2004 and March 2009 for the single symptom of acute vertigo initially thought to be labyrinthine, four were found to have cerebellar infarction of the posterior inferior cerebellar artery area (PICA). All were over 60 years old and had risk factors including hypertension, diabetes mellitus, arrhythmia, and/or hyperlipidemia. Two had trunk ataxia, with magnetic resonance imaging (MRI) showing infarction within a few days. The other two could walk without apparent trunk ataxia, however, it took 4 to 7 days to find the infarction, mainly through neurological, neurootological, and MRI findings. Neurologically, astasia, dysbasia or trunk ataxia were important signs. Neurootologically, nystagmus and electronystagmographic testing involving eye tracking, saccade, and optokinetic patttens were useful.

Restoration of BRAK / CXCL14 gene expression by gefitinib is associated with antitumor efficacy of the drug in head and neck squamous cell carcinoma.

Clinical efficacy of gefitinib (ZD1839, Iressa), which is an inhibitor specific for epidermal growth factor (EGF) receptor tyrosine kinase, has been shown in non-small-cell lung carcinoma patients with EGF receptor mutations, so these mutations are useful marker(s) to find a responder for the drug. Recent studies have shown that the EGF receptor gene mutation is rare in squamous cell carcinoma in the esophageal and head and neck regions. We previously reported that the expression of the chemokine BRAK/CXCL14 in head and neck squamous cell carcinoma (HNSCC) cells was down-regulated by EGF treatment, and that forced expression of BRAK in tumor cells decreased the tumorigenicity of the cells in xenografts. Thus, we investigated the relationship between restoration of BRAK expression by gefitinib and the efficacy of the drug for tumor suppression. We found that EGF down-regulated BRAK expression through the MEK-extracellular signal regulated kinase pathway and that this down-regulated expression was restored by gefitinib in vitro. Oral administration of gefitinib significantly (P < 0.001) reduced tumor growth of xenografts of three HNSCC cell lines (HSC-2, HSC-3, and HSC-4), in female athymic nude mice, accompanied by an increase in BRAK expression specifically in tumor tissue. This tumor-suppressing effect of the drug was not observed in the case of BRAK non-expressing cells. Furthermore introduction of BRAK shRNA vector reduced both the expression levels of BRAK in HSC-3 cells and the antitumor efficacy of gefitinib in vivo. Our data showing an inverse relationship between BRAK expression levels in tumor cells and the tumor growth rate indicate that the gefitinib-induced increase in BRAK expression is beneficial for tumor suppression in vivo.

Soluble form of ephrinB2 inhibits xenograft growth of squamous cell carcinoma of the head and neck.

The ephB4-ephrinB2 system plays an important role in the interaction of tumor cells with endothelial cells (ECs). To assess the role of ephB4 in the in vivo growth of head and neck squamous cell carcinoma (HNSCC), we used ephrinB2-Fc, a fusion protein consisting of the extracellular domain of ephrin-B2 and the Fc portion of human IgG1, as the soluble ligand for ephB4. EphrinB2-Fc injection into HNSCC xenografted mice significantly suppressed xenograft growth, accompanied by a decrease in vessel cross-sectional area, but there was no change in vessel number. EphrinB2-Fc injection also induced the formation of mature blood vessels rich in alpha-smooth muscle actin positive pericytes in the xenograft tissue. In vitro assays revealed that ephrinB2-Fc inhibited the proliferation of human umbilical vein ECs (HUVECs) but not tumor cells. Furthermore, real-time quantitative RT-PCR showed that ephrinB2-Fc down-regulated matrix metalloproteinase-2 mRNA expression in HUVECs and vascular endothelial growth factor-A in tumor cells. These data suggest that treatment with ephrinB2-Fc, the soluble ligand of ephB4, inhibited the growth of HNSCC through vessel maturation/stabilization, preventing leakiness and endothelial sprout formation.

Staging primary head and neck cancers with (18)F-FDG PET/CT: is intravenous contrast administration really necessary?

PURPOSE: The aim of our study was to prospectively evaluate whether intravenous contrast media in integrated positron emission tomography and computed tomography (PET/CT) with (18)F-fluorodeoxyglucose ((18)F-FDG) significantly contributes to evaluation of primary head and neck cancers compared with unenhanced PET/CT, regional contrast-enhanced CT of head and neck (neck CE-CT) and regional magnetic resonance imaging of head and neck (neck MRI). METHODS: Subjects were 42 consecutive patients (35 men, 7 women; age range: 36-91 years) with biopsy-proven primary head and neck cancers. Lesion detection of primary and nodal sites and TNM classification were assessed on a per-patient basis. McNemar test and kappa statistics were employed for statistical analyses. RESULTS: Forty patients (95%) were successfully followed up: 24 patients had nodal disease and 3 had distant metastasis. Contrast-enhanced and unenhanced PET/CT detected 98 and 95% of the primary tumours, respectively, and both detected 92% of patients with nodal disease, which revealed no statistically significant difference. Accuracy for T status was 75 and 73%, respectively, which proved significantly more accurate than neck CE-CT, which had an accuracy of 53% (p = 0.0133 and 0.0233, respectively). Neck MRI correctly classified the T status in 58% of patients; however, no statistically significant difference was found between PET/CT and neck MRI. Contrast-enhanced PET/CT, unenhanced PET/CT, neck CT and neck MRI correctly staged the N status in 90, 90, 79 and 90% of patients, respectively, with no statistically significant difference. Overall TNM classification was correctly classified in 68 and 65% of patients, respectively. Weighted kappa values between enhanced and unenhanced PET/CT for primary tumour detection, nodal detection, T status and N status were 0.655, 1.000, 0.935 and 1.000, respectively. CONCLUSION: We found almost perfect correlation between enhanced and unenhanced PET/CT for lesion detection and initial staging of primary head and neck cancers. Routine contrast administration for PET/CT imaging may not be justified.

Efficacy of concurrent chemoradiotherapy for T1 and T2 laryngeal squamous cell carcinoma regarding organ preservation.

BACKGROUND: Although the survival rate of early-stage laryngeal squamous cell carcinoma (SCC) patients treated by radiotherapy (RT) is sufficient, the larynx preservation rate is unsatisfactory. To improve the larynx preservation rate, such patients have been treated by RT with chemotherapeutic agents. PATIENTS AND METHODS: RT with or without uracil-tegafur (UFT) was performed for T1 cases, and UFT and carboplatin for T2 cases. RESULTS: In T1 cases, 30 patients received RT and 16 patients received concurrent chemoradiotherapy (CCRT). In T2 cases, 28 patients received RT and 45 patients received CCRT. There were no significant differences in the response and survival rates between the treatment methods both in T1 and T2 cases. The 5-year larynx preservation survival rate was improved significantly by CCRT in T2 cases (66.7% vs. 93.3%; p < 0.01). CONCLUSION: CCRT for early-stage laryngeal SCC patients was efficacious to improve the larynx preservation survival rate.

Antiemetic effects of granisetron and dexamethasone combination therapy during cisplatin-containing chemotherapy for head and neck cancer: dexamethasone dosage verification trial.

BACKGROUND: Chemotherapy-induced nausea and vomiting (CINV) remains a significant problem for patients and is associated with a substantial deterioration in quality of life; appropriate use of antiemetic drugs is crucial in maintaining the quality of life in patients undergoing chemotherapy. METHODS: This randomized, crossover trial evaluated the antiemetic efficacy and safety of 8 mg per day (low-dose) and 16 mg per day (standard-dose) dexamethasone, in combination with the 5-HT(3) receptor antagonist granisetron, in 36 patients receiving cisplatin (CDDP)-containing chemotherapy for head and neck cancer. Following chemotherapy, the antinausea/vomiting inhibition rate for each dexamethasone dose was measured. RESULTS: During the 24-h period following administration of chemotherapy (acute phase), the antinausea/vomiting inhibition rates (no nausea and no episodes of vomiting) for 8 mg and 16 mg dexamethasone were comparably high (58.3% and 63.8%, respectively; P = 0.8092). Similar results were seen on days 2-5 following chemotherapy. Efficacy during the acute phase, based on the number of instances of vomiting and degree of nausea, was also comparably high for the two dexamethasone doses (overall efficacy rates were 94.4% and 88.8%, respectively, for 8 mg and 16 mg dexamethasone; P = 0.7637). Both doses maintained an 80% or higher response rate until day 3, and neither dose produced severe side effects. CONCLUSION: The results suggest that granisetron and dexamethasone combination therapy is useful in controlling acute and delayed nausea and vomiting induced by CDDP-containing chemotherapy for head and neck cancer. Furthermore, 8 mg and 16 mg dexamethasone have equivalent antiemetic efficacy.

[Successful treatment results of S-1 administration in 2 patients, one with a remnant tumor of the larynx and metastatic tumors to the lung, and another with a metastatic tumor in the neck from the hypopharynx].

We report two successful remnant and recurrent cases of head and neck cancer treated with S-1. Case 1, a 52-year-old man, was diagnosed as supraglottic laryngeal carcinoma (T3N2cM0, squamous cell carcinoma: SCC) on January 25, 2000, and concurrent chemoradiotherapy (CCRT) was applied. After the treatment, a remnant tumor in the larynx was found by biopsy. He was followed using UFT at 400mg/day because he had refused surgery. Pulmonary metastasis was detected by chest CT on June 14, 2001, and the administration of S-1 was started. After 2 courses, the mass in the lung disappeared, and the primary lesion was also judged to be a complete response(CR). The administration of S-1 is still continuing and remnant tumors have not been found. Case 2, a 76-year-old man, was diagnosed with hypopharyngeal carcinoma (T3N2bM0, SCC) on December 14, 2001, and CCRT was applied resulting in CR in the hypopharynx and the neck. He was followed using UFT at 300 mg/day after discharge. A supraclavicular lymph node became palpable on March 27, 2003. Pathological examination by fine needle aspiration cytology showed SCC, class V. After 2 courses administering S-1 at 100mg/day, the supraclavicular lymph node disappeared. S-1 was changed to UFT at 300 mg/day on July 31, 2003, because adverse events of grade 3 appeared. Administration of UFT was continued for one year. No recurrence has been found for 5 years.

[The role and limitations of FDG-PET in head and neck cancer].

18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a nuclear medicine imaging technique which has been increasingly applied as a diagnostic tool. The usefulness of FDG-PET may be described as follows: I . Early detection of cancer; II. Diagnosis of cancer; III. Detection of nodal or distant metastasis, and double cancer; IV. Detection of unknown primary tumor with metastatic neck lesions; and V. Evaluation of treatment of head and neck cancer. FDG-PET is especially useful to detect distant metastasis, double cancer with head and neck cancer and unknown primary tumor with metastatic neck lymph nodes. The conventional modalities, e. g., CT or MRI, show anatomical images in the body. On the other hand, FDG-PET reveals three-dimensional images of functional processes of the glucose metabolism. FDG-PET can estimate metabolic activity in cancer and is useful in evaluating or monitoring the response to concurrent chemoradiotherapy of the head and neck cancer. However, we should recognize the limitations of FDG -PET. An acute inflammatory disease shows high FDG uptake like cancer. It is difficult to detect early-stage esophageal cancer or to diagnose parotid gland cancer.

[A case of Langerhans cell histiocytosis coincident with severe external ear canal inflammation].

We report a case of Langerhans cell histiocytosis (LCH), a rare disease caused by the proliferation of abnormal Langerhans cells, coincident with severe external ear canal inflammation. A 27-year-old man with a 1-year history of external ear canal discharge was found in computed tomography (CT) to have left temporal bone erosion with tissue granulation. Chest X-ray showed pulmonary fibrosis, necessitating transbronchial lung biopsy that yielded a definitive diagnosis of multisystem, multisite LCH involving the bone, skin, lung, pituitary, thyroid, and lymph node systems. He underwent combination chemotherapy directed by the Japan LCH Study Group. LCH should therefore be considered in the case of a patient with severe external ear canal inflammation coincident with temporal bone erosion.

Involvement of EGFR in the response of squamous cell carcinoma of the head and neck cell lines to gefitinib.

Epidermal growth factor receptor (EGFR) gene mutations are associated with the sensitivity of non-small cell lung carcinomas (NSCLCs) to gefitinib, but such findings have not been reported in squamous cell carcinomas of the head and heck (SCCHNs). Accordingly, we determined whether EGFR gene expression and mutations correlate with the in vitro efficacy of gefitinib in SCCHN cell lines. EGFR status was analyzed in 16 different SCCHN cell lines by polymerase chain reaction (PCR) and direct sequencing for activating mutations, by real-time quantitative RT-PCR, and by Western blot analysis for RNA and protein expression. Using direct sequencing of PCR products from exons 18-23 of 9 SCCHN cell lines, we found a heterozygous EGFR mutation (EGFRmut) with a 2607Gright curved arrow A transition in exon 20 (G/A genotype). The 9 different cell lines that showed this mutation also showed higher sensitivity (lower IC50 values) to gefitinib than cell lines with wild-type EGFR (EGFRwt: G/G genotype) (p=0.016). EGFR protein levels correlated robustly (r=0.76) and significantly (p=0.0007) with EGFR mRNA levels and with IC50 values for gefitinib (r=0.65, p=0.0067). EGFR mRNA correlated with IC50 values (r=0.67, p=0.0046). Our conclusion was that the heterozygous and synonymous transition of the EGFR gene and low EGFR expression levels of mRNA and protein in SCCHN may be reliable predictors of high sensitivity in SCCHN patients to gefitinib.

Anti-tumor effects of telomelysin for head and neck squamous cell carcinoma.

Telomelysin is a telomerase-specific replication-competent adenovirus with telomerase reverse transcriptase (hTERT) promoter, which has shown strong anti-tumor effects on a variety of human cancer cells. Human head and neck squamous cell carcinoma (HNSCC) cell lines and a murine HNSCC (NR-S1) model were used to investigate whether telomelysin (OBP-301) had a therapeutic efficacy for HNSCC. We examined the cell killing effects of telomelysin and the induction of tumor cell apoptosis by telomelysin in vitro. Based on these data, we examined whether telomelysin therapy produced therapeutic benefits in vivo. The results demonstrated that the treatment of telomelysin led to significant tumor regression on the side with subcutaneous NR-S1 tumor. We first confirmed the direct anti-tumor effect of intratumoral telomelysin injections in a murine HNSCC model. Further analyses of the augmented anti-tumor effects revealed that telomelysin increased the source of tumor antigens for immune cells, resulting in the induction of CD4+ and CD8+ T cells responsible for the in vivo tumor regression of treated and untreated tumors. Subsequently, an elevated IFN-gamma production of spleen cells was observed in mice treated with telomelysin. These results raise the possibility that telomelysin enhances the immune response in addition to its direct tumor cell killing activity. These findings suggest that telomelysin is a potent agent for the treatment of HNSCC patients with multiple metastases.

Antitumor effect of gefitinib on head and neck squamous cell carcinoma enhanced by trastuzumab.

The overexpression of EGFR and/or HER-2 is associated with tumor cell resistance to chemotherapy, radiotherapy, disease progression and poor prognosis in patients with a variety of malignant tumors. Treatment combining the EGFR-targeting drug, gefitinib (ZD1839, Iressa) with the HER-2-targeting drug, trastuzumab (Herceptin) has been reported to improve therapeutic efficacy in patients with breast cancer. The purpose of this study was to examine the antitumor effect of this combination on head and neck squamous cell carcinoma (HNSCC) in vitro. Cell proliferation was inhibited significantly in two cell lines. Although IC50 of gefitinib alone against some cell lines was not reached, it was achieved after being combined with trastuzumab. Furthermore, IC50 was lower for the combination than for gefitinib alone in several cell lines. These results suggest that the combination may improve efficacy against HNSCC.