Mamoru Miyaguchi

Expression of Epidermal Growth Factor Receptor in Laryngeal Dysplasia and Carcinoma

The immunoreactivity of epidermal growth factor receptor (EGFR) was studied in laryngeal biopsy specimens from 24 patients. The study comprised 5 cases of normal laryngeal mucosa, 5 cases of dysplasia, 7 cases of well differentiated squamous cell carcinoma, and 7 cases of poorly to moderately differentiated squamous cell carcinoma. EGFR was in general not expressed in normal and dysplastic epithelia, whilst all carcinomas showed a rather strong positive immunoreactivity. There was no significant difference in staining patterns between the well and poorly to moderately differentiated carcinomas. The results suggest that EGFR constitutes a component of neoplastic, but probably not preneoplastic, laryngeal disease. The study failed to reveal any difference in staining pattern between different types of laryngeal squamous cell carcinoma.

A study of the late effects of radiotherapy and operation on patients with maxillary cancer: A survey more than 10 years after initial treatment

One hundred seventy‐one maxillary carcinoma patients who survived more than 10 years after initial treatment were surveyed. Performance status was unrestricted in 35.1% of the patients, slightly restricted in 34.5%, moderately restricted in 21.1%, restricted in 7.0%, and very restricted in 2.3%. Radiation‐induced cataracts on the affected side occurred in 100% of the patients treated with radiation. Good visual acuity was maintained in only 65.8% of the patients, even on the contralateral side. Fifty‐five percent of the patients retained symmetric facial animation due to our policy of conservative therapy. Restricted mouth opening occurred in 32.2% of the patients, taking liquid diet in 21.1%, and middle ear effusion in 26.3%, which were closely linked to maxillectomy operation. This study suggests that avoiding excess radiation dosage, strict control of radiation field, adaption of two portals with 60 grades wedge pair filter, use of appropriate protectors, limiting removal at the maxillactomy, and postoperative care for trismus or tympanic effusion are necessary.

Correlation of Epidermal Growth Factor Receptor and Radiosensitivity in Human Maxillary Carcinoma Cell Lines

To determine the relationship between epidermal growth factor receptor (EGFR) and radiosensitivity, we immunostained cells from three maxillary carcinoma cell lines with an anti-EGFR antibody. The intensity of staining reactivity, determined by means of an image analysis system, was expressed as grey value (0-black to 255-white). The mean grey values for cell lines IMC-2, IMC-3, and IMC-4 were 181, 210, and 222, respectively, and differed significantly (p < 0.001). This indicates that IMC-2 had the highest number of EGFR, followed by IMC-3 and IMC-4. The cells were then irradiated at 1, 2, 4, or 6 Gy, and cell survival was assessed by means of a standard colony-forming assay. IMC-2 had the highest survival rates at 1, 2 and 4 Gy, followed by IMC-3 and IMC-4. Therefore, the survival rates for IMC-2, IMC-3, and IMC-4 after irradiation increased in proportion to the amount of EGFR in each cell line. These results support the findings of previous clinical studies which showed that increased expression of EGFR was associated with higher recurrence rates of glottic and maxillary sinus carcinoma in patients treated with radiation therapy. The amount of EGFR in cells may therefore be associated with their radiosensitivity.

Low frequency of HLA-A*0201 allele in patients with Epstein-Barr virus-positive nasal lymphomas with polymorphic reticulosis morphology

Lymphoproliferative diseases of the nasal cavity and paranasal sinuses occur frequently in Asian countries and are histologically categorized as monomorphic ordinary lymphoma and polymorphic reticulosis (PR) with apparent inflammatory cell infiltration. The large atypical cells in PR show natural‐killer cell nature and frequently contain Epstein‐Barr virus (EBV) DNA. Among the EBV genes involved in latent infection, those encoding EBV latent membrane proteins are frequently expressed in PR. Several cytotoxic T‐lymphocyte (CTL) defined epitopes have been mapped to latent membrane proteins restricted with HLA‐A2, ‐A11 or ‐A24 antigens. Thus, the HLA‐A allele may affect the development of PR. To examine this possibility, HLA‐A alleles of 25 patients with EBV+ PR were determined with low‐resolution polymerase chain reaction‐based typing using HLA‐A locus sequence‐specific primer combinations. The frequency of HLA‐A alleles including HLA‐A2 and ‐A24 antigens in PR patients was lower than that in the normal Japanese population, but the difference was not significant. Since HLA‐A2‐restricted CTL responses are well delineated at the A2‐subtype level, the A2‐subtype of PR cases with HLA‐A2 antigen was further determined by high‐resolution genetic typing. The frequency of HLA‐A*0201 in PR was significantly lower than in the normal population (p=0.0314). The HLA‐A*0201‐restricted CTL responses may thus function in vivo to suppress the development of overt lymphoma. Int. J. Cancer 87:195–199, 2000.

Immunohistochemical Study of Epidermal Growth Factor Receptor in Severe Dysplasia and Carcinoma in situ of the Vocal Cords

The presence of epidermal growth factor receptor (EGFR) was studied in laryngeal biopsy specimens from 14 patients, all with severe dysplasia or carcinoma in situ. All 14 cases showed positive immunoreaction for EGFR. In 5 of the specimens there were also areas with moderate dysplasia, 3 of which showed scattered EGFR positive cells, whilst 2 were negative. In 8 biopsy specimens there were areas with mild dysplasia, but none of them showed any positive immunoreaction for EGFR. Thus EGFR is present in laryngeal severe dysplasia and carcinoma in situ, indicating the potential malignant neoplastic nature of these lesions. The immunostaining for EGFR may be used as an aid to differentiate between severe dysplasia and carcinoma in situ (Group III lesions), moderate (Group II lesions) and mild dysplasia (Group I lesions).

Pigmented squamous cell carcinoma of the alveolar ridge in the oral mucosa

The clinical and morphologic features of a pigmented squamous cell carcinoma of the alveolar ridge in an 81-year-old Japanese woman are reported. The tumor was typical, well-differentiated squamous cell carcinoma but had many melanin-containing cells within it. Electron microscopy showed melanosomes in macrophages, melanocytes, and neoplastic squamous cells. Those in the neoplastic squamous cells seemed to have been excreted from the cytoplasmic processes of melanocytes.

Laryngeal necrosis after combined chemotherapy and radiation therapy

Post-radiation necrosis of the larynx is a major complication after irradiation and has become rare. Recently, combined chemotherapy and radiation therapy has been introduced for head and neck tumours. The authors report a case of laryngeal necrosis after combination therapy for a patient with cervical lymph node metastases of nasopharyngeal carcinoma and review the literature on late laryngeal necrosis. Although radiation-induced laryngeal necrosis has become a rare complication, the combination of chemotherapy and radiation therapy may increase its incidence. We should always consider it as a possible late complication and treat it appropriately.

Extracapsular dissection: Minimally invasive surgery applied to patients with parotid pleomorphic adenoma

Abstract Conclusions: We performed extracapsular dissection (ECD) on 31 patients with pleomorphic adenoma, including 7 deep lobe cases. ECD is minimally invasive and has limited complications compared with other conventional parotidectomy procedures. This is the first report on performance of ECD in patients with deep lobe parotid pleomorphic adenomas. Surgeons who are capsule-conscious can perform ECD with good results. Objective: Pleomorphic adenoma, the most common benign neoplasm occurring in the parotid gland, has a constant frequency of recurrence and facial paralysis in patients after surgery. ECD is one of the surgical procedures performed on patients with these tumors, but its validity is still unclear because of its similarity to enucleation. Methods: We performed ECD in patients with untreated parotid neoplasms that were clinically diagnosed as benign before surgery. Of these, resected samples from 31 patients were histologically diagnosed as pleomorphic adenoma. Results: We achieved resection in patients with pleomorphic adenoma with no permanent facial paralysis or tumor recurrence, with a median follow-up time of 61 months (range 18–125 months).

The Contact Nd-YAG Laser for Oral and Oropharyngeal Malignant Tumors

Nine oral and oropharyngeal squamous cell carcinomas were removed with a contact Nd-YAG laser. Clinical and morphological studies on wound healing and effects of the Nd-YAG laser were performed. The wounds were not sutured and patients did not complain of any severe symptoms. The wound healing was prolonged to 3-6 weeks. Cells and glands degenerated at a depth of 2-3 mm by the direct effects of the laser. The epithelium exhibited acantholysis 5 mm from the site of laser injury. Scanning electron microscopy showed no coagulation or other coated material in the wound created by a surgical knife, while the wound surface by laser consisted of carbonization, well-coated and non-coated areas. These findings varied with the laser power. The coagulation and thermal effects of the Nd-YAG laser resulted in autolysis of tumor cells at least within 5 mm of the cutting surface. The contact Nd-YAG laser was useful for the removal of the malignant tumor in the oral cavity and oropharynx where it is difficult to maintain a generous safety margin.

Multiple primary malignancies in patients with malignant tumours of the nasal cavities and paranasal sinuses

The incidence of multiple primary malignancies (MPM) was analysed in 1297 patients with malignant tumours of the nasal cavities and paranasal sinuses. The patients were followed for a minimum of six years or until death. The incidence of MPM was 3.4 per cent (44/1297) which is lower in patients with malignant tumours of other regions in the upper aerodigestive tract. Five of the 44 patients had second malignancies within previously irradiated areas. There was a difference between the proportion of histologies occurring in irradiated tissues compared with the overall 1297 patients. This finding suggests that radiotherapy may induce a second cancer.