We report thirty three patients treated for nasopharyngeal carcinoma (NPC) in our clinic from 1976 to 1997. They consisted of 24 males and 9 females, and their ages ranged from 17 to 76 years with an average of 56 years. Fourteen patients initially presented with ear symptoms due to tubal insufficiency, 11 with cervical lymphadenopath-y, 6 with nasal Symptoms and 4 with cranial nerve paralysis. The mean interval from the onset of their complaints to the time of difinite diagnosis of NPC was 5.8 months. Seventeen patients (51.5%) had primary sites with T3 or T4. Twenty four (72.7%) had cervical lymphnode metastases.Thirty (90.9%) were classified as stage III or IV.
Radiation therapy is a mainstay of treatment of NPC because of anatomic restrictions and a high degree of radiosensitivity. An average of total radiation dose was 63.9Gy for the primary site except in one patient (28Gy followed by surgery due to poor response to radiation). In two patients, high-dose intracavity radiation by remote afterloading system was, performed. They have been free from disease since then for more than 3 years. Radiation therapy was combined with an administrations of 5-fluorouracil and vitamim A (FAR therapy), or a low-dose of cisplatin in 2 and 5 patients, respectively. Local recurrence was detected in none of these patients and this combined therapy seemed to be effective in controlling the primary lesion, The overall 5-year survival rate was 56.9% (Kaplan-Meier method), however, that of patients with stage IV was still poor; 33.2%. This emphasizes the importance of an early diagnosis of NPC.
Twelve patients underwent surgical resection of the residual tumor at the primary site after radiotherapy. As a surgical approach to the nasopharynx, the transmandibular transpterygoid approach was employed in five patients. This procedure offers a wider exposure of the nasopharynx than either the transmaxillary or the transpalatal approaches. Although distant etastasis was detected in three of the five patients, none of them developed local recurrence. The 5-year survival rate in 12 patients with surgery was 65.6%, which was better than 49.2% in 21 patients without surgery. Neck dissection, was petrformed on 14 patients after radiotherapy. None had cervical recurrence postoperatively. The surgical treatments are recommended for patients with postradiation residual primary tumor and/or cervical metastasis.

View full abstract

The olfactory epithelium has been shown to contain fifth-type cells and microvillar cells and olfactory receptor cells along with supporting and basal cells. However, the morphological differences among them are unknown, especially between the former two, and most of their functions are still unclear. In this study, the fifth-type cell and the microvillar cell in the olfactory epithelium of mouse were micromorphologically investigated by SEM and TEM. With the aim of elucidation their functions, the morphological change in these cells after resection of olfactory bulb were studied. In addition, the changes in the olfactory epihelium after HRP injections into the postganglionic fiber for the trigeminal nerve and the olfactory bulb were examined. The TEM bservation revealed that the fifth-type cell has finger-like microvilli, which are strong and straight. The microvilli were characterized by a specific ore structure consisting of microfilament bundles. On the other band, the microvilli of the microvillar cell were meandering and had no core structure, ndicating that the two cells are clearly different types. By SEM observation, neither the fifth type cell nor the microvillar cell was found in the ormal olfactory epithelium, When the olfactory cillial mat disappeared as a result of recection of the olfactory bulb, the fifth type cell became bservable. On the 300th-day after the resection. it was found thal the olfactory receptor cells had disappeared and the microvilli of the supporting cells were shortened. Thus. the surface structure of the microvillar cell became clearly observable. Then. the microvilli were found to be shorter than those of the fifth-type cell and were distributed radially. Neither the fifth-type cell nor the microvillar cell was not affected by resection of the olfactory bulb. Most of the olfactory vesicles were HRP positive after the HRP injection into the olfactory brlb; however, HRP was not detected in either the fifth-type cells or the microvillar cells. After the HRP injection into the trigeminal postganglionic fiber. it was detectable in part of the nerves in the lamina propria mucosa and the epithelal basement, but not in the fifthe-type cell or mcrovillar cell. These results suggest that the fifth-type cell is a mechanoreceptor for a system other than the olfactory one and the microvillar cell is a kind of supporting cell in an early stage or final stage near eath

View full abstract

Prognostic factors for hearing preservation following observation only versus STI were compared in patients with acoustic neuroma. There were 48 patients with acoustic neuroma treated by fractionated STI. Between 1991 and 1977. patiens were given 36Gy in 20 fractions over 5 weeks (36Gy/2OFr/5wks) to 44Gy/22Fr/6wks followed by a 4Cy boost. A linear accelerator was used for irradiation. Twenty three patients with acoustic neuroma who were followed without any treatment (observation-only group) were selected as matched controls. The largest hearing loss was observed at the frequency of 2kHz in the observation only group and at 1-2kHz in the STI group. Hearing loss at 1kHz was more frequent in the STI group (p<0.01). There were no significant prognostic factors which predicted hearing preservation in the observation-only group. Stereotactic irradiation has been suggested to damage to cochlear nerve function in patients whose cochlear nerve had been impaired already. Tumor control rate of STI appeared to be as good as single fraction radiosurgery rates in the literature and better than in the observation-only group. Hearing preservation rate in the STI group was as good as in the observation-only group and appeared to be better than single fraction radiosurgery. In conclusion, because there were no factors predictive of hearing preservation in the observation-only group, it is difficult to select patients for observation only. Fractionated STI is potentially the treatment of choice, resulting in the same hearing preservation rate as achieved with observation only, although longer follow-up periods are needed.

View full abstract

An immunological study was carried out in 50 patients with etiology unknown sensorineural hearing loss, including the following: 12 low tone deafness, 7 sudden deafness, 8 unilateral deafness, 7 idiopathic bilateral progressive sensorineural hearing loss and 14 other bilateral sensorineural hearing loss. Twenty five out of 50 of the cases demonstrated immunological abnormalities. A full array immunological tests were performed with the following results. High immnunoglobulin titers showed in 18 out of 50 cases. Six cases were positive for antinuclear antibody. The anti-DNA antibody assay revealed high titers in 2 cases. Also, anti-rheumatoid factor antibody assay showed high titers in 6 cases while abnormal values of complements in serum were detected in 6 cases, though an immune complex was demonstrated in only one case. Also, it was noted that six patients with immunological abnormalities have autoimmune diseases. The above results indicated that some cases of etiology unknown sensorineural hearing loss may have an immunological link.

View full abstract

Among tumors of the head and neck, nasal and paranasal sinus papilloma is a relatively rare benign tumor. However, it is different from other benign nasal and paranasal tumors, in histological morphology, and in higher probabilities of recurrence, complication with malignant tumor, and malignant alteration. In this study, we examined clinically and pathologically 30 patients with nasal and paranasal sinus papilloma who underwent operations in our department between 1975 and 1994 The tumor occurred in the opening of the maxillary sinus in 19 patients and in the nasal septum in 7 patients. Destruction of bone was observed in 12 patients. Pathological examination revealed inverted papilloma in 17 patients, exophytic papilloma in 13 patients, and atypia in 4 patients. Recurrence was observed in 9 patients, and malignant alteration was observed in 5 patients. Using paraffin sections, aneuploidy was assessed by flow cytometric DNA ploidy. Diploid in 25 cases (83.3%) and aneuploid in 5 cases (16.7%) were observed. Risk factors of malignant alteration in nasal and paranasal papilloma are considered to be 1) developmental morphology, 2) destruction of bones, 3) atypia in pathology, 4) recurrence before progression to n ralignancy, and 5) the presence of aneuploidy. The 5 patients in whom malignant alteration was observed each showed 4 of the 5 risk factors, suggesting that malignant alteration is most likely to occur in nasal and paranasal papilloma that show 4 or 5 risk factors. The period up to malignant alteration varies; in one patient, it was more than 10 years. Therefore, follow-up observation over a long period is required.

View full abstract

clinical study was performed of 83 patients with hypopharyngeal cancer treated in the Sapporo Medical University Hospital from 1982 to 1995. Five year cumulative survival rate was 34.9% in the whole group and 37.2% in the radical surgical and/or radiation treatment group. In the radiation treatment group, the patients with T1, T2. N0 or N1 stage disease, especially those whose original disease responded almost completely to 40Gy irradia-tion, showed high tumor control rates following full-dose irradiation with or without radical neck dissection. In the radical surgery group, the patients with T4 or N2 stage disease showed better prognosis than those in the radiation group. However, among the patients with N3 lymph node metastases, there were no long-term survivors in either the radiation or the surgery groups.

View full abstract

Between 1986 and 1997, 124 patients with tumors i)f major salivary glands (93 parotid tumors, 31 submandibular gland tumors) were assessed by fine-needle aspiration cytology (FNAC). The 124 cases included 28 cases of primary malignant tumors and 96 cases of benign lesions, The preoperative fine-needle iagnoses were compared with postoperative pathologic findings. Sensitivity for malignancy was 64%, and specificity was 99%. Overall accuracy was 91%. and the predictive value for malignancy was 95%. FNAC allowed determination of histogenesis in 13 (68%), of the 19 cases cytologically diagnosed as malignant, and in 72 (71%) of the 105 cases cytologically diagnosed as benign. The diagnostic accuracy for histologic diagnosis of malignant neoplasms, pleomorphic adenoma. and Warthin's tumor was 46%, 73% and 82%, respectively. The predictive value for specific histologic diagnosis of malignancy, pleomorphic denoma, and Warthin's tumor was 100%, 91%. and 100%, respectively. The diagnostic accuracy and the predictive value for histologic diagnoses were elatively high (⟩70%) for squamous cell carcinoma. adenocarcinoma, malignant lymphoma, pleomorphic adenoma, and Warthin's tumor. Adenoid cystic carcinoma and low-grade malignancies such as mucoepidermiod carcinoma and acinic cell carcinoma were the lesions, most, frequently misdiagnosed.

View full abstract