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T Dokiya

Publications and source records attributed to T Dokiya.

At least 37 records · Page 2Linked to original sources
PubMed1986

Local control of squamous cell carcinoma of the mobile tongue: an experience of different modalities.

From 1966 through 1983, 163 patients with squamous cell carcinoma of the mobile tongue were treated. Fifty-two patients were staged as T1N0, 77 as T2N0, 14 as T2N+, 8 as T3N0, 7 as T3N+, and 5 as T4. The follow-ups were complete. Treatment modalities varied considerably during that period, because of increasing difficulty to use radioactive sources by regulations. All T3N+ and T4 patients died shortly after treatment. Five year absolute survivals for the T1N0, T2N0, T2N+, and T3N0 patients were 87%, 60%, 27% and 63%, respectively. Local recurrence free survivals at 5 years for the T1N0, T2N0, T2N+, and T3N0 patients were 72, 48, 58, and 88%, respectively. Local recurrence free survivals seemed to be better with Ra-226 needling +/- external irradiation (EXT) than other modalities. Because many patients with local recurrence were salvaged, ultimate local-disease-free survivals should also be considered. They were 96 and 70% at 5 years for the T1N0 patients treated with Ra-226 +/- EXT, and with surgery +/- EXT, respectively; the corresponding figures for the T2N0 patients were 83 and 64%. For these reasons, Ra-226 needling may be preferable to other modalities as initial treatment. Although cervical failures did not develop after 2 years of treatment, late local recurrences were rather common, even after 5 years. Long-term follow-up is mandatory for the management of the patients, and analyzing and comparing the results.

Adult↗
PubMed1986

[Combined effects of radiation and 5-FU derivatives].

The combined effects of X-ray irradiation and 5-FU derivatives (5-FU, tegafur, HCFU) treatment were investigated in mouse adenocarcinoma-755. Mice were given a single irradiation 5 Gy or 10 Gy of 6-MV X-rays and orally administered 5-FU derivatives at the time of pre- or post-irradiation. Under these conditions, antitumor activity and survival time were compared between pre- and post-irradiation. Under these conditions, antitumor activity and survival time were compared between pre- and post-irradiation, in combination with 5-FU, tegafur or HCFU. The antitumor effects and survival time were greater for pre-irradiation treatment than for post-irradiation. Among 5-FU derivatives, the highest combination effect was shown by HCFU, followed by 5-FU and tegafur. The concentration of 5-FU in the tumor was correlated with the antitumor effect of each drug.

Adenocarcinoma↗
PubMed1986

[Present status of brachytherapy].

High dose rate, remote-afterloading intracavitary irradiation (RALS) and low dose rate, interstitial irradiation were discussed. In Japan, RALS is now a standard treatment for uterine cervix carcinoma. In interstitial radiotherapy, radium sources, because of their poor conditions of protection and excessively long half-life, are being replaced by several new radioactive elements, such as 60Co, 125I, 125Cs and 192Ir. These have suitable characteristics for afterloading and safety protection. Among them 192Ir has become common source, not only for intraoral cancer, but also various other tumors including rectal, breast, and bile duct cancers.

Brachytherapy↗
PubMed1985

[Radiotherapy of laryngeal cancer].

In general, the control rate with radiotherapy in early laryngeal cancer is close to 90%, probably the highest control rate that can be expected with this therapy. In other words, about 10% of patients still fail to respond to the therapy. This probably means nothing but the fact that the sigmoid response curve has reached the plateau. This ratio has remained unchanged, while physical and biological dose distribution has remarkably been improved these three decades. In this study, therefore, we discussed the cause of radioresistance in squamous metaplasia of laryngeal epithelium as the origin of laryngeal cancer.

Brachytherapy↗
PubMed1983

Value of computed tomography for radiation therapy of tumors of the nasal cavity and paranasal sinuses.

The role of computed tomography (CT) in connection with irradiation was evaluated in 60 patients with malignant tumors of the nasal cavity and paranasal sinuses. The extent of the tumors was well demonstrated at CT. The infratemporal fossa was involved in 33 patients, extension to the intracranial cavity was found in 6, and in 16 extension to the contralateral side. Such information is of great help in radiation treatment planning. On the other hand, CT was less valuable for evaluating the effect of radiation therapy.

Carcinoma, Squamous Cell↗
PubMed1982

Computed tomography of malignant tumors of the nasal cavity and paranasal sinuses.

Staging of malignant tumors of the nasal cavity and paranasal sinuses by computed tomography (CT) was studied in a total of 49 patients, 33 with squamous cell carcinoma and 16 with tumors of other histologic types. Involved sites by the tumor were studied, and clinical staging was made using CT findings alone according to AJC classification for maxillary sinus tumors. Surgical findings for comparison were available for most cases. Of 33 squamous cell carcinomas and of 16 tumors with other histologic types, the maxillary sinus was the site of origin in 29 and eight, respectively. Of these 37 maxillary sinus tumors, 11 were staged T3, 26, T4, and none was staged T1 or T2. None of these tumors were down staged, and one T3 was upstaged after surgical procedures, although all sinuses were not explored in some cases. Sinusitis due to obstruction was indistinguishable from the tumor without bone destruction. And the determination of the site of origin was difficult in some cases. Despite these, CT should be used for pretreatment evaluation of the tumors of these sites.

Adenocarcinoma↗
PubMed1982

Radiation therapy of early glottic carcinoma. A Japanese experience.

From 1969 and through 1979, 105 patients with T1 N0M0 and T2 N0M0 glottic carcinoma were treated with irradiation alone. The minimum follow-up period was 2 years, and only one patient was lost to follow-up. There were 62 T1a lesions, 14 T1b, 19 T2 with normal mobility, and 10 T2 with impaired mobility; relapses occurred in 10, 4, 1 and 3 patients, respectively. All but one patient who relapsed had local recurrence with or without nodal or distant spread. One patient had only nodal metastasis. Six of the 18 relapses were successfully cured by surgery. None of the patients who had nodal or distant spread survived. The relapse rates had no clear relation to total dose or TDF value. T1 lesions treated through larger fields (greater than or equal to 25 cm2) had a lower relapse rate than lesions treated through smaller fields, but the difference was not statistically significant.

Adult↗