[Rupture of an internal carotid artery pseudoaneurysm after irradiation for a nasopharyngeal carcinoma--case report].

The primary treatment of nasopharyngeal carcinoma (NPC) has been external radiotherapy. Rupture of an internal carotid artery (ICA) pseudoaneurysm is a rare complication of irradiation therapy for a nasopharyngeal carcinoma. A 78 years old man had a history of NPC treated with radiotherapy in 1993. He was admitted to the hospital because of epistaxis. Angiography showed an ICA pseudoaneurysm pointing medially to the nasopharynx. Coil embolization of the ICA was performed, but cerebral infarction occurred. Internal carotid artery (ICA) pseudoaneurysms are an uncommon but potentially lethal condition. Angiography is the mainstay of diagnosis of the aneurysm and planning the embolization of the ICA. We should be more aware of this complication in NPC patients.

Distribution of thermal neutron flux around a PET cyclotron.

The number of positron emission tomography (PET) examinations has greatly increased world-wide. Since positron emission nuclides for the PET examinations have short half-lives, they are mainly produced using on-site cyclotrons. During the production of the nuclides, significant quantities of neutrons are generated from the cyclotrons. Neutrons have potential to activate the materials around the cyclotrons and cause exposure to the staff. To investigate quantities and distribution of the thermal neutrons, thermal neutron fluxes were measured around a PET cyclotron in a laboratory associating with a hospital. The cyclotron accelerates protons up to 18 MeV, and the mean particle current is 20 µA. The neutron fluxes were measured during both 18F production and C production. Gold foils and thermoluminescent dosimeter (TLD) badges were used to measure the neutron fluxes. The neutron fluxes in the target box averaged 9.3 × 10(6) cm(-2) s(-1) and 1.7 × 10(6) cm(-2) s(-1) during 18F and 11C production, respectively. Those in the cyclotron room averaged 4.1 × 10(5) cm(-2) s(-1) and 1.2 × 10(5) cm(-2) s(-1), respectively. Those outside the concrete wall shielding were estimated as being equal to or less than ∼3 cm s, which corresponded to 0.1 µSv h(-1) in effective dose. The neutron fluxes outside the concrete shielding were confirmed to be quite low compared to the legal limit.

[Long-term histological outcome for the larynx after Gore-Tex medialization thyroplasty].

OBJECTIVES: We studied the long-term histological response of the human larynx to Gore-Tex implant and evaluated whether its biocompatibility. STUDY DESIGN: Retrospective histological study. METHODS: We conducted medialization laryngoplasty with expanded polytetrafluoroethylene (ePTEE or Gore-Tex) in a patient with vocal-fold paralysis. A strip of Gore-Tex was folded several times and inserted into the pocket preserving the inner perichondrium through a thyroid cartilage window. The patient died 12 months later and we histologically analyzed the larynx. RESULTS: No evidence was seen of foreign body granuloma, migration, extrusion, or infection. A modest inflammatory response with a fibrous capsule was present around implants. We confirmed the infiltration of abundant collagen and numerous fibroblasts into the microporous implant structure. CONCLUSION: Histological examination results suggest that Gore-Tex implants are safe and biocompatible with the human larynx. A slight inflammatory response and infiltration of fibrous tissue into the implant itself demonstrated that Gore-Tex implants are immunologically well tolerated.

[Delayed facial nerve palsy after otologic surgery].

Delayed facial nerve palsy (DFP) is rarely experienced after otologic surgeries that do not directly touch the facial nerves, such as tympano-mastoidectomy, cochlear implants, and stapes surgery, and is troublesome to both surgeons and patients if it happens. Here, we report 7 cases of DFP, including one case that developed DFP after endolymphatic sac surgery. The ratios of occurrence were as follows: 0.7% (2/305) for tympano-mastoidectomy, 0.8% (3/354) for cochlear implant, 0.4% (1/260) for stapes surgery and 1.0% (1/98) for endolymphatic sac surgery. All otologic surgeries, except for endolymphatic sac surgery, exposed the chorda tympani, and all surgeries, except for stapes surgery, underwent drilling for a mastoidectomy. Furthermore, DFP was always observed ipsilaterally to the operated ear after otologic surgeries and was never seen after benign parotid tumor surgery or total laryngectomy. Therefore, there may be a strong relationship between DFP and the procedures, used during otologic surgeries.

[Effects and use of the suture direction mimicking only the force action of the lateral cricoarytenoid muscle in arytenoid adduction combined with thyroplasty type I].

Isshiki's arytenoid adduction combined with thyroplasty type I is a useful procedure for correcting the membranous vocal fold atrophy and the height difference between the two vocal folds, particularly in patients with a large posterior glottal chink and atrophy. Conventional arytenoid adduction (Isshiki's arytenoid adduction) is designed to place a suture through the muscular process of the arytenoid attached anteriorly to the thyroid ala, stimulating the function of the thyroarytenoid muscle and lateral cricoarytenoid muscle. Combining with thyroplasty type I, the suture direction of conventional arytenoid adduction prevented inserting implant material into the pocket of the thyroid cartilage window. In contrast to conventional arytenoid adduction, the suture direction in our approach is anchored anteroinferiorly, mimicking only the action of the lateral cricoarytenoid muscle (the major adductor of the larynx). It is used the thyroid cartilage window in thyroplasty type I to determine the direction of the lateral cricoarytenoid muscle. After approaching the muscular process based on Isshiki's arytenoid adduction, two nylon sutures are tied across the muscular process or the lateral cricoarytenoid muscle nearby the muscular process. The cricoarytenoid joint is not dislocated. One of the sutures was anchored to the inferior rear corner of the thyroid cartilage window to be used with thyroplasty type I and the other was anchored to the rear lower margin of the thyroid lamina. Gore-tex medialization thyroplasty is done after tying the sutures on the thyroid ala. Subjects were 30 unilateral paralytic dysphonia. Maximum phonation of all patients improved significantly after surgery. The preoperative and postoperative mean maximum phonation times were 6.0 and 17.9 seconds. No major complications occurred in this study. Our approach effectively combined arytenoid adduction and thyroplasty type I for patients with severe insufficient glottic closure.

[Four cases of hypopharyngeal cancer treated with docetaxel, cisplatin, and 5-FU followed by radiotherapy and/or neck dissection].

We treated 4 patients with hypopharyngeal cancer, each of whom had a complete response after 2 cycles of chemotherapy with docetaxel, cisplatin, and 5-FU followed by radiation and/or neck dissection. Twenty-one months to 2 years after this therapy, 3 patients had no recurrence and no metastasis with their laryngeal framework and function preserved. Chemotherapy including docetaxel, cisplatin, and 5-FU is a useful treatment for early head and neck cancer.

Spindle cell carcinoma of the larynx.

Four rare cases of spindle cell carcinoma of the larynx are reported and the histo-pathological and immuno-histochemical findings are described. The spindle cell carcinoma involved the right vocal cord of an 88-year-old and an 86-year-old male patients and the anterior commissure of a 76-year-old and a 68-year-old male patients. Two patients underwent total laryngectomy, one patient extirpation under laryngomicrosurgery and one radiation therapy. All were well controlled thereafter and there was no recurrence. Surgery seemed to be the most satisfactory therapeutic approach and radiation therapy was effective in a patient with relatively small tumor. The histo-pathological and immuno-histochemical analysis in one patient revealed a sarcoma-like component of the carcinoma and the findings suggested that this was the result of a metaplastic change in the mesenchyme without inflammatory changes.

[A case of neck metastasis from hypopharyngeal carcinoma successfully treated with TS-1].

We report a case of hypopharyngeal carcinoma with recurrent neck metastasis. Preoperative chemoradiation and pharyngo-laryngo-esophagectomy with bilateral neck dissection was done as first-line therapy. Six months later, the carcinoma metastasized to the right paratracheal lymph node. Because of resistance to chemoradiation (CBDCA) as second-line therapy, we administered TS-1 for the treatment after 60 Gy radiation. The chemotherapy with TS-1 resulted in complete response by diagnostic imaging (CT). There was no sign of recurrence for 1 year after 5 courses of treatment. TS-1, which allows oral chemotherapy on an outpatient basis, would be a useful drug for treatment with radiotherapy in patients with advanced and/or recurrent head and neck cancer.

Highly precise measurements of the relative gamma-ray intensities for 56Mn and 72Ga.

Precise relative gamma-ray intensities of 56Mn and 72Ga produced by neutron irradiation of natural Mn3O4 and enriched 71Ga2O3 (99.8%) were measured by an HPGe detector with highly-precisely calibrated detection efficiencies. As both nuclides exhibit no beta branch to the ground state, the absolute emission probabilities of the 846.8 keV gamma ray for 56Mn and 834.0 keV gamma ray for 72Ga were determined to be 0.9888+/-0.0014 and 0.9553+/-0.0005, respectively.

Precise measurement of the emission probability of the 543 keV gamma ray of 199Pt.

199Pt has been produced by neutron irradiation of enriched 198Pt (95.71%) metal powder, and precise measurements have been made of the gamma-ray emission probabilities by means of 4pibeta-gamma coincidence apparatus and a live-timed two-dimensional data-acquisition system. Daughter 199Au decays with a half-life of 3.139 d, and therefore the measured disintegration rate had to be corrected. The absolute emission probability of the 543.0 keV gamma ray was determined to be 0.1174+/-0.0007 from the gamma-ray intensity and the corrected disintegration rate.

[A case of posterior wall cancer of the hypopharynx treated with docetaxel followed by radiation].

We treated a 67-year-old female with hypopharyngeal cancer (T2N0) in the posterior wall, who had a complete response after two cycles of chemotherapy with docetaxel followed by radiation. Five years after this therapy she has had no recurrence and no metastasis, with preserved laryngeal framework and function. Docetaxel is useful for treating early head and neck cancer.

[A clinical study of 213 patients with laryngeal cancer].

We retrospectively analyzed 213 patients--197 men and 14 women aged 40 to 87 years--with laryngeal cancer treated at our department from September 1986 to December 1997. The male to female ratio was about 12:1. Cases included 120 glottic (56.3%), 90 supraglottic (42.3%), and 3 subglottic (1.4%). Radiotherapy for early cases and surgery, mainly total laryngectomy for T3 and T4 were conducted first. The 5-year cause-specific survival by site was 97.6% glottic and 77.5% supraglottic. The five-year survival was 88.6% overall. Local control was 83.8% in glottic T1a and 84.6% in glottic T1b. The 3-year preservation of the larynx was 89.1% in glottic T1a and 92.3% in glottic T1b. Distant metastases were observed in 14 cases, mostly to the lung, bones, and liver. At high risk for distant metastasis were those with supraglottic T3-T4, N1, N2b, or pN2c.

Determination of the emission probabilities of the principal gamma-rays for 134Cs to a high precision.

While multi-gamma-ray emitting nuclides such as 75Se, 134Cs and 152Eu have reasonably well-defined decay scheme, some inconsistencies still remain. Detailed evaluations and weighted-mean analyses result in the recommendation of gamma-ray emission probabilities with small uncertainties, although significant deviations exist in the measured values. Therefore, the gamma-ray emission probabilities of 134Cs have been measured to a high precision after an extremely accurate calibration of detection efficiency. The resulting data agree extremely well with the evaluated values in IAEA-TECDOC-619 (IAEA, X-ray and gamma-ray standards for detector calibration, IAEA-TECDOC-619, IAEA, Vienna, 1991).

Indications for the radiation therapy of carcinoma of the hypopharynx

As indicaçöes para o tratamento radioterápico (RT) do carcinoma da hipofaringe, revendo nossa experiência clínica recente, säo as seguintes: 1) Radioterapia radical: lesöes de estádio T precoces sem metástases cervicais; confinadas à parede posterior ou metade superior do seio piriforme (menos de 10% dos casos) deveriam ser tratados com radidoterapia exclusiva. Todavia, quando a resposta tumoral é pequena aos 40Gy, radioterapia em campo localizado deve ser abandonada e indica-se a cirurgia. Como resultado, estes casos säo categorizados como grupo de radioterapia pré-operatória. 2) Radioterapia pré ou pós-operatória: os casos N0-N2b com diferentes estádios b com diferentes estádios T pela classificaçäo da UICC (1987) säo candidatos para tratamento com finalidade curativa. Quando reconstruçäo em um único tempo da faringe é difícil, radioterapia pré-operatória deve ser indicada. Pelo contrário, quando a recontruçäo é feita no mesmo tempo da faringolaringectomia, radioterapia pós-operatória é indicada. Esta seleçäo deve ser decidida levando-se em conta a extensäo tumoral exata no momento do diagnóstico. 3) Radioterapia paliativa: outros casos avançados säo tratáveis paliativamente; todavia, näo se observa sobrevida a longo prazo. Pela análise dos padröes de recorrência, o controle regional deveria melhorar a curabilidade deste tipo de câncer. O controle efetivo de nodos clinicamente positivos (NI-3) pode ser obtido com a combinaçäo de esvaziamento cervical e radioterapia na dose de pelo menos 50 Gy. Considerando-se cada localizaçäo (nivel) de linfonodos com metástases, o campo adequado de irradiaçäo deve incluir a possível subclínica. Além disso, para casos com pescoço clinicamente negativo (N0), 50Gy ou mais devem ser administrados eletivamente, também cobrindo um campo adequado