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C Konaka

Publications and source records attributed to C Konaka.

89 records · Page 5Linked to original sources

Clinical measurement of tumor fluorescence using a new diagnostic system with hematoporphyrin derivative, laser photoradiation, and a spectroscope.

Hematoporphyrin derivative (HPD) is retained by malignant tumors and emits fluorescence with peaks of 630 and 690 nm wavelength when HPD is exposed to light. It is therefore theoretically possible to make a diagnosis of malignant tumors by detecting the fluorescence of HPD. The authors developed a spectroscope system compatible with fiberoptic endoscopes to analyze the shape of the fluorescence light spectrum. We could clearly recognize the HPD-specific fluorescence in human cancer foci. This system can be applied to the measurement of the relative amount of HPD absorbed in superficial tumor tissue before the photodynamic therapy. This might suggest the extent of tumor. The clinical diagnostic applications of this system are described in this study.

Aged↗

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↗

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↗

Hematoporphyrin derivative and laser photoradiation in the treatment of lung cancer.

Photoradiation therapy (PRT) was performed in 13 lung cancer cases and in one case of severely atypical squamous metaplasia following administration of hematoporphyrin derivative (HpD). The HpD is activated by visible red light (630 nm, 90 to 400 mW) from an argon dye laser. The cytocidal effects were due to the activation of the HpD, since 400 mW of power has in itself no effect on normal epithelium, even with long-term exposure. HpD is retained longer by malignant tissue than by normal tissue. Therefore, the lesions were irradiated with the red laser beam, delivered by a quartz fiber inserted through the instrumentation channel of the fiberoptic bronchoscope, 48 hours or more after intravenous injection of 2.5 to 4.0 mg/kg of HpD. A total of 14 cases received PRT. In one, two small, smooth-surfaced, squamous cell carcinoma tumors in the right B2b of a 74-year-old man who had refused surgery disappeared three days after HpD-photoradiation, and the patient remained disease-free 16 months after the treatment. In 12 cases of centrally located lung cancer local effects were obtained in all. However, there was no significant improvement in survival, attributable to the fact that all were advanced-stage cases. One patient with severely atypical squamous metaplasia requested treatment, and complete disappearance of metaplastic atypic was obtained.

Adenocarcinoma↗

Fiberoptic bronchoscopic laser photoradiation for tumor localization in lung cancer.

Hematoporphyrin derivative (HpD) administration and laser photoradiation were combined to clarify the system's clinical applicability in localizing lung cancer tumors. It was used in 16 cases of lung cancer and in one case of severely atypical squamous metaplasia. Tumors were irradiated 48 hours after intravenous injection of 2.0 to 4.0 mg/kg HpD and fluorescence observed. Fluorescence was seen in 13 lung cancer cases in the case of squamous metaplasia, but results were negative in three of the cases of lung cancer. Among the positive cases was one of occult cancer and two invading the trachea, difficult to recognize by conventional fiberoptic bronchoscopy, as was the severely atypical squamous metaplasia. In the three lung cancer cases not fluorescing, the tumors were obscured by blood, necrotic tissue, or normal mucosa. The method holds promise in the diagnosis of malignant tumors. Nevertheless, it needs further refinement and more studies to elucidate definitive differentiation between malignant and severely atypical, nonmalignant tissue.

Adenocarcinoma↗

Reversibility of bronchial cell atypia.

Various degrees of cellular atypia were induced in the bronchial epithelium of dogs by means of repeated submucous 20-methylcholanthrene injections. Thereafter, the 20-methylcholanthrene treatment was stopped, and the outcome of the bronchial cell atypias in individual dogs was studied using cytomorphological and cytochemical methods. The results suggest that the various degrees of 20-methylcholanthrene-induced cellular atypias, including those cytologically interpreted as malignant, may reflect reversible cellular alterations which disappear after removal of the carcinogen. Similar observations were made in a group of cigarette smokers who, after malignant-appearing cells were observed in the sputum material, stopped smoking or significantly reduced their cigarette consumption.

Animals↗

Cytologic features based on the expression of E-cadherin and catenins in lung adenocarcinoma.

OBJECTIVE: To investigate the relationship between E-cadherin-associated cell-to-cell adhesion and cytologic features in preoperative cytologic lung adenocarcinoma specimens. STUDY DESIGN: Evaluation of the relationship between cell-to-cell adhesion, formation of cellular clusters and frequency of single cells in 31 cases of primary lung adenocarcinoma, collected by brush and needle cytology preoperatively. RESULTS: Most cases with remarkable overlapping of cells in compact cellular clusters and a few solitary cells maintained cell-to-cell adhesion. Cellular clusters that had a slight tendency to overlap, a small cell-to-cell adhesion area and a high frequency of solitary cells tended to lack E-cadherin-associated cell-to-cell adhesion. CONCLUSION: Formation of cellular clusters and the appearance of solitary cancer cells are closely related to E-cadherin-associated cell-to-cell adhesion. Therefore, it is highly likely that cytologic features may indicate malignant behavior, such as local invasion and lymph node metastasis, in primary lung adenocarcinoma.

Adenocarcinoma↗