Sho Matsubara

Extranodal Non-Hodgkin's Lymphoma in the Head and Neck: Irradiation and clinical course

A retrospective analysis was performed of localized extranodal non-Hodgkins lymphomas in the head and neck region treated with irradiation. Histopathologic reevaluation revealed 94 per cent with a diffuse type. The lesions were as a rule locally cured with doses ranging from 30 to 50 Gy. Relapses in localized stage I and II patients were, however, not seldom observed in distant extranodal sites. Gastrointestinal relapse in cases with lesions originally located in Waldeyers ring was thus frequently observed, and the probability of multiple or systemic involvement should be considered also when the disease is located in the oral cavity or sinus region. The value of systemic examination for staging purposes is discussed.

Radiation injury in a patient with unusually high sensitivity to radiation

Radiation therapy is usually given with the assumption that interindividual variations in radiosensitivity are small, except for some patients with hereditary diseases associated with increased sensitivity. Recently, we observed radiation induced pericarditis in a breast carcinoma patient, in whom clinical signs, blood counts and chromosome analysis after in vitro irradiation of blood suggested a state of unusually high radiosensitivity. No evidence of constitutional chromosome abnormality was found in karyotypic analysis with the G-banding technique.

A comparative study of dose distribution of a high-energy electron beam and chromosome aberration frequencies.

Electron beam therapy is usually employed for the treatment of tumours located at or near the surface of the body, because the electron beam gives a high dose near the surface, but falls off rapidly with increasing depth beyond the level of the 80% depth dose. Isodose curves for radiotherapy have been obtained using physical methods, but have rarely been investigated on the basis of living human cells. In the present study, lymphocyte chromosome analysis was employed as a biological dosemeter for comparison with the isodose curve measured physically. The peripheral blood was exposed to a 14 MeV electron beam in a plastic tube set in a specially made test-tube stand immersed in a water tank. The chromosome aberration frequencies induced by irradiation of about 95% of peak dose at a depth of 31 mm were found to be higher in value than those induced at a depth of 17 mm where the peak dose had been determined physically. Three gray of irradiation given to whole blood in the presence of contrast medium gave rise to a slight enhancement of radiation-induced chromosome aberration frequencies in the lymphocytes exposed at a depth of 17 mm, but a slight decrease at 31 mm.

COMBINED EFFECTS OF ULTRASOUND AND IONIZING RADIATION ON LYMPHOCYTE CHROMOSOMES

The effects of ionizing radiation and ultrasound upon the induction of chromosomal-type aberrations and sister chromatid exchanges were investigated. No statistically significant increase in the frequencies of dicentric and ring chromosomes or sister chromatid exchanges was discovered after ultrasound exposure alone at the diagnostic level. Nor could elevated frequencies of these phenomena be found following exposure to ultrasound before or after ionizing radiation, compared with those resulting from an equivalent dose of ionizing radiation alone. However, simultaneous exposure to ultrasound and ionizing radiation seemed to induce a slight enhancement of sister chromatid exchanges, although no significant change was noted in the yields of dicentric and ring chromosomes.

Chromosome aberrations in the peripheral lymphocytes induced by brachytherapy and external cobalt teletherapy

In the present study, the induction efficiencies of chromosome aberrations were analyzed in patients receiving various modalities of interstitial radiotherapy with small radiation sources in the oral cavity area and compared with those in patients treated with external telecobalt irradiation in the thoracic region. Further, as a local nonstochastic effect, the acute mucosal reaction was investigated. The mucosal reaction in the area treated by brachytherapy reached a maximum at two to three weeks after the implantation. The frequencies of dicentrics plus rings of peripheral lymphocytes, on the other hand, revealed rapid increases and approached plateau levels as early as two days after the implantation. The whole-body effects, evaluated on the basis of the chromosome aberration frequencies of peripheral lymphocytes in the patients who underwent brachytherapy, were compared with the effects observed in those patients treated with external radiotherapy or bleomycin injection and discussed with regard to their effectiveness in control of the tumor and side effects. The radiation doses used in the patients who received brachytherapy or a single external irradiation were found to exert the same effects on the chromosome aberration induction. However, even in the case of brachytherapy in which whole-body side effects were believed to be trivial, the peripheral lymphocyte count was temporarily reduced to one half or less of the preirradiation level. An equivalent whole-body dose of 50 cGy was obtained from the frequencies of dicentrics and rings.

Dose distribution of neutron beam and chromosome analysis.

Chromosome analysis using peripheral lymphocytes is a sensitive and reliable indicator of the biological effect of radiation at low radiation doses. In the present study, using this chromosome aberration analysis, we tried to investigate the radiation dose distribution within and around the radiation field of a 6 MeV neutron beam. The efficient induction of dicentrics and rings at the irradiation of neutrons compared to those of gamma or X rays especially in a lower dose range, results in a dominant linear component in the linear quadratic model in the dose response relation of a chromosome aberration formation. A marked increase of RBE (relative biological effectiveness) in a lower dose range of neutrons was demonstrated. The radiation doses of the neutron beam as a function of depth, estimated from the yields of dicentrics and rings in a water phantom revealed a fairly good agreement with doses that were physically obtained. The radiation portal margin of the neutron beam was demonstrated to be not as sharp due to a wide penumbra. This wide penumbra and high RBE value, especially at lower dose range of the neutron beam may contribute to the induction of secondary malignancies in the normal tissue surrounding the tumor mass.

Effects of Washing on Phytohemagglutinin Responsiveness of Lymphocytes from Irradiated Patients

The peripheral lymphocytes from irradiated patients generally have a reduced capability to respond to phytohemagglutinin (PHA). Whether a relationship exists between PHA-responsiveness and chromosome aberration frequencies was examined by washing the lymphocytes with culture medium. The results indicate that the defect in lymphocyte activation in patients receiving radiation therapy was caused by some reversible changes in the lymphocyte membrane directly associated with radiation exposure rather than by a radiation induced suppressor substance secondarily acting on the lymphocyte membrane.

RETICULOSARCOMATOSIS ORIGINATING FROM SKIN—A CLINICOPATHOLOGICAL STUDY

The case is that of a 65 year‐old male with reticulosarcomatosis originating from the skin. There were multiple tumors composed of reticulum cells located only in the skin, particularly around the large joints. The entire course of illness was three years and five months, during which period regression by irradiation, recurrence, or new forma tion of tumors were repeatedly seen. At the end systemic tumor spread not only of the skin but also in various visceral organs including lymph nodes occurred.

Relation Between Extension of Non-Hodgkin'S Lymphoma and Lymphographic Findings

The relationship between the degree of lymph node foaminess observed in bipedal lymphadenograms and absolute peripheral lymphocyte counts in non-Hodgkins lymphoma was analyzed with regard to the initial location, clinical stage, histologic subtype, and bulkiness of the disease. In the nodal type of disease with supra-diaphragmatic presentation, an inverse relation was often found between the peripheral lymphocyte count and the foaminess score. However, if the disease originated in the infra-diaphragmatic regions no such relation was found. The implications of these observations are discussed.