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Biomedical subjects

Y Hayata

Publications and source records attributed to Y Hayata.

At least 73 records · Page 4Linked to original sources
PubMed1984

Hematoporphyrin derivative and photoradiation therapy in early stage lung cancer.

Photoradiation therapy (PRT) with administration of hematoporphyrin derivative (HPD) was performed in ten cases of early stage central-type lung cancer of which six cases were treated by PRT alone due to inoperability because of poor pulmonary function in five and refusal of surgery in one. Four cases were resected after PRT. In the former, complete tumor remission was obtained in all six and in the latter, complete tumor remission was seen in one and significant remission in three. In the nonresected cases four cases are disease-free at 17-41 months and the remaining two cases died of chronic obstructive lung disease and cerebral infarction 16 and 31 months after PRT, respectively. The resected cases are disease-free 7-32 months after surgery. Indications of PRT in early stage lung cancer are discussed according to histological findings of resected specimen.

Aged↗
PubMed1984

Photoradiation therapy with hematoporphyrin derivative in early and stage 1 lung cancer.

Photoradiation therapy with hematoporphyrin derivative was used in 13 cases of early-stage and eight cases of stage 1 central-type lung cancer. The lesions were photoradiated superficially or interstitially by an argon dye laser with a power of 80 to 600 mW for 10 to 40 minutes at 48 hours or more after intravenous injection of 2.5 to 5.0 mg of hematoporphyrin derivative (Photofrin) per kilogram of body weight. Eight of the 13 early-stage cases were treated with photoradiation only, due to poor pulmonary function or refusal of surgery. Macroscopically complete tumor remission was obtained in all eight cases, and the patients are free of disease at 13 to 41 months after photoradiation therapy, except two patients who died at 16 and 31 months after therapy, due to chronic obstructive pulmonary disease and cerebral infarction, respectively. Five cases were resected following photoradiation therapy. Complete remission was demonstrated histologically in two and significant remission in three, and all are free of disease at 7 to 30 months after surgery. The histologic type was squamous cell carcinoma in all cases. In eight stage 1 cases (seven squamous cell carcinomas and one large cell carcinoma), surgery was performed in three after photoradiation therapy, and the remaining five cases were not resected, due to poor pulmonary function or refusal of surgery. Apparent complete remission was obtained in two of the nonresected cases (one died of cerebral infarction at 27 months, while recurrence occurred 15 months after photoradiation therapy in the other) and significant remission in six. In three nonresected cases with significant remission, two patients died of pneumonia unrelated to the photoradiation treatment at 11 and 4 months, respectively, after such treatment. The reason why only significant remission was obtained in early and stage-1 cases was due to the penetration of the argon dye laser beam being limited due to the location of the tumor or the degree of intrabronchial or extrabronchial growth in eight cases. In one other case the power of the argon dye laser beam was insufficient due to technical difficulties. Indications for photoradiation therapy were discussed in relation to the histologic findings in the specimens following such therapy. Procedures were performed under local anesthesia in all cases. Our results indicate that with present methods, photoradiation therapy is effective in cases of superficial invasion or intramural invasion, but curative effects can hardly be expected in cases growing beyond the normal muscular or cartilaginous layer.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗
PubMed1984

[Surgical indications of small cell carcinoma of the lung].

A statistical analysis of 143 cases of small cell carcinoma treated at the Department of Surgery of Tokyo Medical College in the 15-year period from January 1968 to December 1982 was performed. The results suggest that surgery is not indicated in any oat cell case, with the possible exception of an extremely rare early stage case. However, since here is a significant difference in the survival of stage I and II cases of the intermediate cell type, surgery can be indicated in certain such cases. Even in such cases surgery should be thought of as merely one step of induction therapy. In addition, it is necessary to tailor adjuvant chemotherapy, keeping in mind that the most frequent causes of death in cases of small cell carcinoma of the lung are local failure, metastasis to intraabdominal organs and to the brain.

Carcinoma, Small Cell↗
PubMed1983

Fiberoptic bronchoscopic photoradiation in experimentally induced canine lung cancer.

The potential of diagnostic and therapeutic applications of a system using hematoporphyrin derivative (HpD) and laser photoradiation for the localization and treatment of canine lung cancer experimentally induced in the bronchi was studied. Seven cases of canine invasive squamous cell carcinoma were used in this experiment. A dose of 2.5-3.0 mg/kg body weight HpD was administered intravenously in each dog forty-eight hours prior to examination for fluorescence. The violet light source was a krypton ion laser beam. The beam was transmitted via a quartz fiber inserted through the fiberoptic bronchoscope, and an image intensifier was used to detect the fluorescence from the bronchial foci. An argon dye laser was used for treatment of the foci with red light. Six of seven dogs with squamous cell carcinoma revealed fluorescence at the foci. Conversely, the bronchi of controls, consisting of normal dogs, showed no fluorescence. Three dogs with squamous cell carcinoma received treatment. The therapeutic system consisted of photoradiation with an argon dye laser beam also transmitted via a quartz fiber inserted through the fiberoptic bronchoscope and a dose of 2.5-3.0 mg/kg body weight HpD was administered intravenously 72 hours before the procedure. All carcinoma cases showed complete responses.

Animals↗
PubMed1983

Hematoporphyrin derivative and laser photoradiation in the diagnosis and treatment of bladder cancer.

Diagnosis and treatment of 8 patients with malignant bladder tumors were performed with intravenous administration of hematoporphyrin derivative, followed by krypton-ion laser violet light photoradiation and argon-dye laser red light photoradiation therapy. Fluorescence permitting localization and evaluation of the lesion was recognized in all 8 patients. Photoradiation with red argon-dye laser light obtained complete remission in 6 patients, with followup from 6 to 18 months. To our knowledge this is the first report describing total regression of bladder tumors obtained by photoradiation. Swelling and edema were noted within 20 minutes after argon-dye laser photoradiation therapy of bladder tumors. Necrosis and partial covering of the tumor by a whitish necrotic mass were noted after 3 days. The whitish mass covered the entire tumor at 7 to 14 days. Gradual exfoliation of the mass was followed by disappearance of the tumor and regeneration of normal mucosa at 9 to 10 weeks.

Adult↗
PubMed1983

Indications for endoscopic Nd-YAG laser surgery in the trachea and bronchus.

Nd-YAG laser surgery via the fiberoptic bronchoscope can vaporize lesions causing airway obstruction or stenosis located from the trachea to segmental bronchi with minimized danger of bleeding, and improve ventilatory disturbances. 35 lesions in the trachea and bronchus consisting of 27 malignant lesions and 8 benign lesions were treated with endoscopic Nd-YAG laser surgery. The procedures were performed under local anesthesia, and no significant side effects were recognized. The lesions was irradiated with 20-80 W. power. In most cases a continuous wave was used, but in cases of early stage squamous cell carcinoma intermittent irradiation of 0.5 second laser spots were used. In 21 of 35 cases effective results were obtained. The non-effective results obtained in 14 cases were considered to be due to inexact preprocedural evaluation of the extent of the lesions. Effective results were obtained in 11 of 13 lesions located in the trachea, in 3 of 5 lesions in the trachea and bronchus and in 7 of 17 lesions in the bronchus. Tumor in the trachea with severe ventilatory disturbance is a good indication for Nd-YAG laser surgery to rapidly alleviate symptoms. But in cases of lung cancer, indications even as a palliative procedure are limited to those cases in which the lung parenchyma distal to the stenotic portion is viable. However, the indications for this procedure as a curative modality are extremely limited.

Adult↗
PubMed1983

[Laser and cancer therapy].

Two kinds of laser were employed in the treatment of cancers of various organs: a high energy vaporization therapy by a Nd-YAG laser and a photoradiation therapy (PRT) by an argon dye laser (red light with 630 nm wave length) after i.v. administration of hematoporphyrin derivative (HpD). In the former, the lesion was vaporized with a power of 40-80 W with continuous wave or pulse wave transmitted endoscopically. Improved condition was obtained in 59.3% among 27 malignant lesions of the trachea and bronchi. The indications of this method were discussed in relation to the tumor location and type of growth. In PRT the lesion was photoradiated with a power of 100-2,000 mW for 10-30 minutes, 48 hours or more after i.v. injection of 2.5-5.0 mg/kg HpD. PRT was performed in 170 cancer cases consisting of 69 cases of lung cancer, 9 cases of esophageal cancer, 22 cases of gastric cancer, 18 cases of bladder cancer and other 52 cases of various organs. In 29 cases of early stage cancers complete tumor remission was obtained in 65.5%, especially in early stage central type lung cancer. Local effect was obtained in all advanced cases. The method is also available to reduce the extent of resection or to widen the indications of surgery preoperatively. However, there are many problems in PRT such as the activation mechanism of HpD, diagnosis of early stage cancer candidates for PRT, indications and limitations.

Carcinoma, Adenoid Cystic↗
PubMed1983

[Lung cancer].

Lung cancer is characterized by a varied histologic background and as a result has a wide range of histologic types compared to cancer of other organs. There is remarkable difference in malignancy according to histologic type, therefore a definitive diagnosis before treatment is essential to determine therapeutic strategy. Recently definitive diagnostic rates of 99% have been obtained by various diagnostic procedures. The value of surveys especially those including sputum cytology is discussed. Also laser therapy with Nd-YAG laser and/or administration of hematoporphyrin derivative plus photoradiation by an argon dye laser and tumor localization with fluorescence photoradiation by a krypton ion laser are discussed.

Adenocarcinoma↗