PubMed Health⌕ Search

Biomedical subjects

Keiichi Ichimura

Publications and source records attributed to Keiichi Ichimura.

26 records · Page 2Linked to original sources

Results of multimodality therapy for squamous cell carcinoma of maxillary sinus.

BACKGROUND: A wide variety of modalities, including surgery, radiation therapy, and chemotherapy, alone or in combination, have been used for the treatment of squamous cell carcinoma (SCC) of the maxillary sinus to obtain better local control and maintain functions. However, there is still much controversy with regard to the optimum treatment. METHODS: From 1987 to 1999, 33 patients with SCC of maxillary sinus were treated at the Department of Otolaryngology-Head and Neck Surgery, University of Tokyo Hospital. The treatment consisted of 30-40 grays (Gy) of preoperative radiotherapy with concomitant intraarterial infusion of 5-fluorouracil and cisplatin followed by surgery and 30-40 Gy of postoperative radiotherapy, for tumors without skull base invasion. For tumors invading the skull base, preoperative systemic chemotherapy with or without radiotherapy was performed, instead of intraarterial chemotherapy, then followed by skull base surgery. The surgical procedures varied according to the extent of tumor. Results were compared with those of the 108 patients treated in our hospital from 1976 to 1982. RESULTS: Partial maxillectomy was performed in 2 T2 patients and 12 T3 patients. Total maxillectomy was performed in 1 T2 patient, 3 T2 patients, and 7 T4 patients. Skull base surgery was performed in eight T4 patients. Orbital content and hard palate were preserved in 22 patients and 18 patients, respectively. The overall 5-year survival rates were 86% in T 3 patients and 67 % in T4 patients, respectively. CONCLUSIONS: Our multimodal treatment has provided favorable local control and survival outcome with good functional results.

Adult↗

Stomal recurrence after total laryngectomy for squamous cell carcinoma of the larynx.

OBJECTIVE: Stomal recurrence after total laryngectomy is one of the most serious issues in the management of laryngeal carcinoma. The management of stomal recurrence, including chemotherapy, radiotherapy, and surgery, has been reported as unsatisfactory. STUDY DESIGN AND SETTING: From 1985 to 1995, 69 patients underwent total laryngectomy for the treatment of laryngeal cancer at the University of Tokyo Hospital. To identify the risk factors for stomal recurrence, we analyzed these patients according to various clinicopathological factors. RESULTS: Stomal recurrence developed in 6 of 69 patients who underwent total laryngectomy for laryngeal carcinoma. Statistical analysis reveals that primary site, preoperative tracheotomy, and paratracheal lymph node metastasis are significant risk factors for stomal recurrence. CONCLUSION: Intensive follow-up should be performed for patients with glottic carcinoma who had preoperative tracheotomy, paratracheal lymph node metastasis, or both to detect stomal recurrence at an early stage.

Adult↗

Phenotype of DFNA11: a nonsyndromic hearing loss caused by a myosin VIIA mutation.

OBJECTIVES/HYPOTHESIS: To characterize the audiovestibular phenotype of DFNA11, an autosomal dominant nonsyndromic hearing impairment caused by a mutation in the myosin VIIA gene (MYO7A), including whether DFNA11-affected subjects have retinal degeneration as is characteristic of Usher syndrome type 1B, caused by different MYO7A mutations. STUDY DESIGN: Retrospective study of audiovestibular and ophthalmological data in a Japanese family linked to DFNA11. METHODS: Otoscopic examination and pure-tone audiometry were performed in all participants in the family. Selected subjects underwent additional examinations including speech discrimination scoring, acoustic reflex measurements, Békésy audiometry, evoked and distortion-product otoacoustic emissions, auditory brainstem responses, and bithermal caloric testing; visual acuity, ocular tonometry, slit-lamp examination, ophthalmoscopy, and electroretinography; and computed tomography of the temporal bone. RESULTS: Most affected individuals had moderate cochlear hearing loss beginning in the second decade and progressing at all frequencies. Variable degrees of asymptomatic vestibular dysfunction were present. Computed tomography showed normal inner and middle ear structures. No evidence suggested retinitis pigmentosa. CONCLUSIONS: The phenotype of DFNA11 is postlingual, nonsyndromic sensorineural hearing loss with gradual progression. Showing moderate hearing loss with asymptomatic variable vestibular dysfunction and no retinal degeneration, the DFNA11 phenotype is mildest among phenotypes caused by MYO7A mutations.

Adaptor Proteins, Signal Transducing↗

Nonsyndromic hearing loss caused by a mitochondrial T7511C mutation.

OBJECTIVES: The aims of the present study were to identify a mutation in a Japanese family showing nonsyndromic sensorineural hearing loss and to relate the mutation to characteristics of patients, including audiovestibular findings. STUDY DESIGN: Familial cohort study. METHODS: Mutation analysis was performed using genomic DNA extracted from blood samples. Subjects underwent audiovestibular examinations, including pure-tone audiograms, tympanometry, self-recording audiometry, acoustic reflex threshold, speech discrimination testing, evoked and distortion-product otoacoustic emissions, auditory brainstem responses, and caloric testing. RESULTS: We identified a T7511C mutation in the mitochondrial tRNA(Ser(UCN)) gene previously reported in one other family. The degree of heteroplasmy for the T7511C mutation ranged from 84% to 92%, and did not correlate with age at examination or severity of hearing loss. Extensive audiologic evaluation suggested both cochlear and retrocochlear involvement. CONCLUSION: Families with maternally transmitted nonsyndromic hearing loss should be investigated for mutations in the tRNA(Ser(UCN)) gene.

Adult↗

High-dose glucocorticoids inhibit proliferation of rat olfactory epithelium.

Glucocorticoids (GCs) are commonly prescribed for treatment of olfactory dysfunction. However, the effects of GCs on olfactory epithelium are not well known. We investigated the effects of high-dose GCs on proliferating cells of olfactory epithelium. Five adult male rats (300 g) received a single daily subcutaneous dose of vehicle containing 0.3 mg dexamethasone (DEX) for 9 days (DEX+ group), and a control group received vehicle alone (DEX- group). We compared sections from the two groups for numbers of Ki67-positive cells. The mean number of Ki67-positive cells per 500 olfactory epithelial cells was 9.6 for the DEX+ group and 58 for the DEX- group (significant difference). We conclude that high-dose GC suppressed proliferation of olfactory epithelium. We suggest that high-dose GC suppresses cytokines and growth factors, resulting in secondary suppression of proliferating ability.

Animals↗

[Induced hypotension for endoscopic sinus surgery].

The purpose of the present investigation is to examine whether induced hypotension can improve the dryness of the surgical field in endoscopic sinus surgery (ESS). ASA physical status I and II adult patients with chronic sinutitis undergoing ESS were studied. All patients were not premedicated. Anesthesia was induced with propofol and maintained with sevoflurane and fentanyl. The patients were allocated randomly into two groups. In patients of Group C, mean arterial blood pressure (MAP) was maintained around 80 mmHg. In Group H, sodium nitroprusside was infused to maintain controlled hypotension with MAP around 60 mmHg. Blood loss, dryness of the surgical field, volume of fluid infusion and urine output, and surgical as well as anesthetic time were compared. Blood loss and dryness of the surgical field were significantly different between the groups. Volume of infused fluid, urine output, and surgical as well as anesthetic time were not significantly different. Induced hypotension with sodium nitroprusside improved surgical conditions and decreased blood loss in ESS.

Adult↗

[Adverse reactions to TS-1 for outpatients with recurrent head and neck cancer].

To examine the adverse reactions to TS-1 for patients with recurrent head and neck cancer, five patients with locoregional recurrences and two with distant metastasis were enrolled in the present study and took TS-1 as outpatients. All patients underwent irradiation with or without surgery before administration of TS-1. One patient was given 100 mg of TS-1 daily, and six patients were given 120 mg of TS-1 daily. Thirteen courses consisted of the regimen of four weeks of TS-1 administration followed by two weeks of intermission, nine courses consisted of the regimen of two weeks of administration followed by one week of intermission, and seven courses consisted of the regimen of two weeks of administration followed by two weeks of intermission. Anemia, leukopenia, neutropenia, and liver dysfunction were often observed as adverse reactions to TS-1 administration. Grade 3 bilirubinemia was observed in only one course, but other adverse reactions consisted of grade 1 or grade 2. Almost all adverse reactions returned to normal after the cessation of drug administration. Based on these results, we conclude that TS-1 is a safe drug for the treatment of outpatients with recurrent head and neck cancer.

Adult↗