Search

From 1977 to 1989, 214 patients with stage I and II cervical cancer were treated with two-axial conformational irradiation to the whole pelvis and Ra-intracavitary irradiation at the Department of Radiotherapy, Aichi Cancer Center Hospital. We evaluated the treatment results in comparison with the results of patients treated by conventional methods in our affiliated hospitals. Furthermore, we analyzed the factors that influenced primary and distant failures. The total dose for the whole pelvis was 4000-4560 cGy/5 weeks, and the brachytherapy dose was 2000-2800 cGy at point A. The cumulative 5-year survival, recurrence-free survival and regional control rates were 82.8%, 91.7% and 93.0% for stage I B, and 70.7%, 79.9% and 90.7% for stage II. These results were almost the same as those of the conventional group. Grade 3 recto-sigmoidal complications were observed in three of 94 patients in the conventional group and none of 214 in the conformational group. This difference was statistically significant. From these results, we conclude that two-axial conformational whole-pelvis irradiation is useful for the reduction of late complications.

Whole-pelvis irradiation with the two-axial conformation technique has been performed in cervical cancer since 1976. In 1990 this technique was improved by obtaining target areas from serial CT images instead of axial transverse tomograms. The aim of this study was to show the advantage of the new two-axial conformation technique compared with the old type of conformation technique, and also with conventional techniques using DVH of normal tissues. The uniformity of dose within the high dose-region and fit to the target areas observed in the new type were better than those in the old type. This improved result was most remarkable in rectal DVH. The new two-axial conformation technique was also compared with the two-opposed technique and box technique. With the new type, cumulative irradiated volume in rectum of more than 40 Gy was reduced to 37% of that with the two-opposed technique. In bladder and intestine, the smallest volume irradiated to more than 40 Gy was observed using the new two-axial conformation technique. With these results, we conclude that the new two-axial conformation technique for whole-pelvis irradiation is suitable to conform the high dose region with the target region in the pelvis, and at the same time to protect the surrounding normal tissues.

Forty patients with T2 cancer of the tongue treated with external irradiation plus radium implants at Aichi Cancer Center were reviewed retrospectively to analyze the influence of overall treatment time on local control. One hundred percent (11/11) local control was achieved in patients irradiated within 35 days, in contrast to only 52% (13/25) local control in those irradiated over 35 days. This result indicates that prolonged overall time is associated with loss of local control. This prolongation is mainly due to the prolonged interval between external and interstitial irradiation. The interval was likely to be longer because of enhanced acute radiation mucositis, especially in patients administrated bleomycin during external irradiation. External irradiation should be followed by interstitial irradiation as soon as possible to keep overall time shorter.

To define the role of radiotherapy in the treatment of supraclavicular lymph node (SCN) metastasis after initial surgery for breast cancer, a retrospective review of 55 patients with ipsilateral SCN metastasis after (extended) radical mastectomy was undertaken. In most cases, SCN metastasis is a manifestation of the systemic dissemination, because 87% of the patients developed second recurrence in 2 years after radiotherapy to SCN. However, the response to radiotherapy closely related to the survival after radiotherapy. 3 year-survival of the patients showing complete response was 42% while of the patients showing partial response was 9%. Six out of 34 mastectomized patients with sole SCN metastasis survived more than 3 years without evidence of recurrence following radiotherapy to SCN. It can be suggested that radiotherapy to SCN metastasis is not always palliative treatment, and has potency to improve the prognosis of the mastectomized patients. The prognostic factor of the patients with SCN metastasis was also referred. The time interval from initial surgery until SCN recurrence (disease free interval) has prognostic significance, because it indicates the natural course of each tumor. Presence of metastasis other than SCN at the time of first recurrence and poor response to radiotherapy predict worse prognosis.

The clinical usefulness and the optimal dose of Z-100 for the treatment of leukopenia caused by radiotherapy for malignant tumors was evaluated in a double-blind study comparing 20 micrograms and 30 micrograms injections of Z-100 and inosine (Z-20, Z-30 and IN group, respectively). The effective rate according to the evaluation by the attending physicians was 67.4%, 79.1% and 48.9% in the Z-30, Z-20 and IN groups, respectively, with a significantly higher efficacy rate for the Z-20 group than for the IN group. The frequency of adverse reactions was 14.3%, 3.9% and 5.6% in the Z-30, Z-20 and IN groups, respectively, with the highest rate in the Z-30 group, but there was no significant difference among the three groups. The useful rate based on total evaluation considering the effective rate and the safety profile in each group was 60.8%, 77.3% and 46.8% in the Z-30, Z-20 and IN groups, respectively, with the highest rate in the Z-20 group showing significant difference from that in the IN group. The above data confirmed the clinical usefulness of Z-100 and suggested that the optimal dose was 20 micrograms twice weekly for Z-100.

The clinical usefulness of Z-100 (Z group) for the treatment of leukopenia caused by radiotherapy for malignant tumors was evaluated by comparing it with that of L-cysteine (L group) by the double-blind method. For 178 complete cases, there were no significant differences in the time-course of the WBC during radiotherapy between the two group. However, for cases with a large field of irradiation (15 X 15 cm = 225 cm2), the mean WBC count in the L group decreased more than that in the Z group. The Z group showed comparable or superior efficacy for the treatment of leukopenia in the L group although there were no significant differences. Adverse reactions were observed in 5.66% and 2.94% in the Z and L groups, respectively, without any significant difference between the groups. The utility rate, useful or better, was 73.9% and 69.2% in the Z and L groups, respectively, showing a slightly higher rate in the Z group than in the L group, although the difference between the two groups was not significant. These results confirmed that Z-100 has comparable or superior efficacy to L-cysteine for the treatment of leukopenia caused by large field radiotherapy for malignant tumors.