Kohji Asakura

The effect of adenotonsillectomy in children with OSA

Adenotonsillar hypertrophy and abnormal facial morphology are thought to be important for the occurrence of obstructive sleep apnea syndrome (OSA). We evaluated the effects of adenidectomy and/or tonsillectomy and the relationship between the treatment results and facial morphology in 134 children with OSA. Significant improvements in apnea-hypopnea indes (AHI) and lowest blood oxygen saturation (SaO2) were noted and 78.5% of the patients improved after adenoidectomy and/or tonsillectomy. Additional operations were needed in two out of 13 cases of the adenoidectomy group and two out of four cases of the adeno-monotonsillectomy group. In the adenotonsillectomy group, the unimproved children tended to have smaller tonsils, narrower epipharyngeal airspace, and more poorly-developed maxillary and mandibular protrusion than the improved children.

Prognostic factors of nasopharynx tumors investigated by MR imaging and the value of MR imaging in the newly published TNM staging

PURPOSE To examine the usefulness of MR imaging for predicting local control of nasopharyngeal carcinoma (NPC) and the value of MR imaging in the newly published fifth edition of the TNM classification. METHODS AND MATERIALS We studied 29 patients with NPC with MR imaging and CT before and after treatment. Staging was done according to the fourth and newly published fifth editions of the International Union Against Cancer (UICC) staging system. The radiotherapy protocol was designed to deliver 66 to 68 Gy to the primary tumor and clinically involved nodes. RESULTS MR proved better than CT at identifying obliteration of the pharyngobasilar fascia, invasion of the sinus of Morgagni, through which the cartilaginous portion of the eustachian tube and the levator veli palatini muscle pass, invasion of the skull base, and metastases to lymph nodes in the carotid and retropharyngeal spaces. All seven patients without invasion of the pharyngobasilar fascia had local control. The local control rates of patients with invasion of the skull base were not good (60 to 73%). There was no apparent relationship between tumor volume determined by T1-weighted MR images and local control when the tumor volume was more than 20 cc. The newly published N staging system appears to successfully identify the high-risk group for distant metastasis as N3. In our series, four of five patients with N3 disease developed distant metastases. CONCLUSION Deep infiltration of the tumor is a more important prognostic factor in NPC than tumor volume. Since the newly published T staging system requires a search for tumor invasion into soft tissue such as parapharyngeal space and bony structures, MR imaging may be indispensable for the newly published NPC staging system.

Effects of thromboxane A2 receptor antagonist (Bay u 3405) on nasal symptoms after antigen challenge in sensitized guinea pigs.

To define the role of thromboxane A2 (TxA2) in allergic rhinitis, we examined the effects of the TxA2 receptor antagonist Bay u 3405 (1, 3 and 10 mg/kg, orally) on nasal symptoms, changes in total airway resistance (TAR), histamine hypersensitivity and eosinophil infiltration into the nasal mucosa induced by topical antigen challenge in actively sensitized guinea pigs. Nasal symptoms (number of sneezes and scratches) were significantly inhibited by pretreatment with Bay u 3405, in a dose-dependent manner. We noted a biphasic increase in TAR after antigen challenge. The first peak response of TAR (177.5 +/- 6.1%, mean +/- SE) was partially but significantly inhibited by Bay u 3405 at 10 mg/kg (142.8 +/- 4.3%, p < 0.01). The second peak response of TAR (181.0 +/- 13.4%) was also inhibited by Bay u 3405 at 3 mg/kg (120.3 +/- 3.1%) and 10 mg/kg (125.2 +/- 9.4%) (both, p < 0.01). The histamine hypersensitivity induced by antigen was inhibited by Bay u 3405 at 15 mg/kg (p < 0.05). Moreover, the mean eosinophil infiltration into the nasal mucosa induced by antigen (644.1 +/- 202.6/both sides of the nasal septum) was inhibited to 137.8 +/- 69.0 by Bay u 3405 at 10 mg/kg (p < 0.05). In conclusion, our results suggest that TxA2 may play an important role in allergic rhinitis in guinea pig models.

Solitary fibrous tumor of the parotid gland extending to the parapharyngeal space

Abstract Solitary fibrous tumors (SFT) arise in the pleura and less commonly in extrapleural sites. Head and neck regions have included the nose and paranasal sinuses, soft palate, epiglottis, thyroid, parotid and submandibular glands, as well as the infratemporal fossa and parapharyngeal space. We report a case of SFT arising from the parotid gland and extending to the parapharyngeal space. To our knowledge, this is the fourth case of SFT originating from the parotid gland and is the largest of its kind among the extrapleural lesions described. The characteristics revealed by computed tomography and magnetic resonance imaging are presented.

Evaluation of the Role of Adenotonsillar Hypertrophy and Facial Morphology in Children with Obstructive Sleep Apnea

We evaluated the role of adenotonsillar hypertrophy and facial morphology in children with obstructive sleep apnea (OSA) and compared these data with an age-matched control group. We performed cephalometric analysis to evaluate facial morphology using lateral facilal roentgenograms. Adenotonsillar and maxillary hypertrophy was remarkable in OSA children. Maxillary protrusion was significantly smaller in the OSA group than in the control group in older children (5-9 years old). Mandibular protrusion was significantly smaller in the OSA group even at younger ages (1-2 years old). The hyoid bone was significantly lower in the OSA group than in the control group at age 3-6 years. Both environmental factors due to upper airway obstruction and genetic factors are suspected as causes of abnormal facial morphology in OSA children.

Radiotherapy for Kimura's disease: the optimum dosage.

PURPOSE To evaluate retrospectively the optimum dosage of irradiation for Kimuras disease. METHODS AND MATERIALS Twenty patients with Kimuras disease were treated with radiotherapy. The sex ratio was 19 males to 1 female. The mean ages at onset, initial treatment, and radiotherapy were 26.2, 29.5, and 32.2 years, respectively. Radiotherapy was mainly applied for residual or recurrent tumors. The eosinophil count increased by more than 10% in 18 of the 20 patients. In most instances, irradiation was given through a single field with dosages ranging from 20 to 44 Gy. RESULTS At the completion of radiotherapy, a marked response in tumor size was noted in all cases. The minimum follow-up was 48 months. Local control was obtained in 23 of 31 lesions (74.1%). At dosages of < or =25 Gy, 26-30 Gy, and > 30 Gy, local control was obtained in 2 of 8 (25.0%), 9 of 10 (90.0%), and 12 of 13 sites (92.3%), respectively. CONCLUSIONS Radiotherapy is an effective treatment for Kimuras disease. This strongly suggests that no surgical procedure other than a biopsy should be carried out. The radiation field should be limited to the lesion and swelling of the adjacent lymph nodes as much as possible, with a optimum dosage of 26-30 Gy regardless of tumor size.

Topical Antigen Provocation Increases the Number of Immunoreactive IL-4-, IL-5- and IL-6-Positive Cells in the Nasal Mucosa of Patients with Perennial Allergic Rhinitis

To evaluate the role of Th2-type cytokines in the nasal mucosa which has been repeatedly exposed to antigen, an immunohistological study for IL-4, IL-5 and IL-6 was performed in patients with perennial allergic rhinitis and non allergic rhinosinusitis. The numbers of immunoreactive (ir)-IL-4, ir-IL-5 and ir-IL-6-positive cells were significantly higher in allergic mucosa than in nonallergic mucosa. In allergic mucosa, the numbers of these ir-cytokine-positive cells were significantly higher in the antigen-challenged site than in the control site. When the patients were divided into an early group (4-6 h after challenge) and a later group (15-25 h after challenge), only the change of ir-IL-4-positive cells was remarkable in the former group, whereas those of the ir-IL-4, ir-IL-5 and ir-IL-6-positive cells were significant in the latter group. These results suggest that antigen-induced upregulation of IL-4, IL-5 and IL-6 is important in the pathogenesis of perennial allergic rhinitis.

Topical CTLA4–Ig Suppresses Ongoing Mucosal Immune Response in Presensitized Murine Model of Allergic Rhinitis

Allergic rhinitis is thought to be mediated by CD4+ T cells producing Th2–associated cytokines. Optimal Ag–specific T–cell activation requires the engagement of T–cell receptor with antigen (Ag) in the context of MHC, and the engagement of appropriate costimulatory molecules. One of the most well–characterized costimulatory pathways is the interaction of B7/CD28–CTLA4 molecules. Recent studies have suggested that the costimulatory pathway may influence the development of Th2 immune responses. The objective of this study was the examination of the role of B7/CD28–CTLA4 costimulatory pathway in the pathogenesis of ovalbumin (OVA)–induced immune response in presensitized murine model of allergic rhinitis. Systemically presensitized BALB/c mice significantly developed Ag–induced early phase nasal symptoms, nasal hyperresponsiveness to histamine, nasal eosinophilia, serum levels of OVA– specific IgE and Th2–associated cytokines following repeated topical Ag challenges. Topical administration of CTLA4–Ig during nasal challenges inhibited Ag–induced nasal symptoms and histamine hyperresponsiveness. We also found a significant reduction in nasal lavage eosinophilia and serum levels of OVA–specific IgE. Furthermore, CTLA4–Ig treatment significantly decreased interleukin (IL)–4 content in nasal tissue, while there was no significant change in IL–5 or IFN–γ levels. These results suggest that B7/CD28–CTLA4 costimulatory pathway mediates the development of ongoing Th2 immune responses and plays a major role in regulating allergic disease, such as allergic rhinitis.

Prognostic Factors and Treatment Outcome in Non-Hodgkin's Lymphoma of Waldeyer's Ring

Prognostic factors and treatment outcome of 71 patients with non-Hodgkins lymphoma of Waldeyers ring were analyzed retrospectively. In univariate analyses, unfavorable prognosis was associated with primary disease in the base of the tongue, stage III-IV diseases, B-symptoms, high-grade histology, T-cell phenotype, elevated serum LDH levels, decreased peripheral blood lymphocyte counts, and negative response on delayed type hypersensitivity skin reactions. Multivariate analysis showed that stage III-IV and T-cell phenotype were significant independent risk factors for death. In stage I-II lymphomas, patients with unilateral large or bilateral cervical lymph node involvement had a poorer prognosis. In stage I-II lymphomas with intermediate or high-grade histology, patients who had received radiotherapy with MTCOP-P chemotherapy (pirarubicin, cyclophosphamide, vincristine, methotrexate with leucovorin rescue, peplomycin, and predonisolone) showed significantly better 5-year disease-free survival rate compared with patients treated with radiotherapy alone.

Effects of Anti-IL-5 Monoclonal Antibody on the Murine Model of Nasal Allergy

IL-5 is known to be closely related to the infiltration, activation and proliferation of eosinophils. In this study, we evaluated the in vivo effects of anti-IL-5 monoclonal antibody (mAb) in the murine model of nasal allergy. The mAb treatment inhibited the antigen-induced late phase eosinophilia, but had no effects on the number of basophilic cells. It also inhibited early phase nasal symptoms, and tended to inhibit histamine hypersensitivity. These findings suggest that IL-5 plays an important role in the pathogenesis of allergic nasal disorders.