International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Sep 1989
The role of post-operative radiation in the prevention of heterotopic ossification in patients with post-traumatic acetabular fracture.
Heterotopic ossification (HO) with subsequent pain and limitation of motion of the lower extremity is a common and significant problem for patients who suffer traumatic acetabular fracture (TAF). The incidence of heterotopic ossification is markedly increased for patients requiring surgical repair depending on the degree of trauma and the type of surgical repair necessary. Radiation therapy (RT) has proven to be the most effective surgical adjunct for the prevention of heterotopic ossification in patients undergoing total hip replacement (THR), but has not been reported in patients with traumatic fracture and repair. ⋯ Even though the incidence of severe heterotopic ossification after radiation therapy for total hip replacement is approximately 5% and for traumatic acetabular fracture patients it is double (10%), the actual incidence of heterotopic ossification without radiation therapy is different in the two conditions. For total hip replacement, the incidence is about 30% and for traumatic acetabular fracture it is 50%. Radiation therapy has again proven itself to be an excellent surgical adjunct to prevent heterotopic ossification, this time in traumatic acetabular fracture patients.
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 1989
Patterns of change in the physics and technical support of radiation therapy in the USA 1975-1986.
Information on the patterns of personnel and related equipment support and availability at various types of radiation oncology facilities are included in the Facilities Master List surveys conducted by the American College of Radiology. This paper summarizes the surveyed data obtained during 1975-1986. ⋯ The use of 60Co units has been progressively decreasing. Almost all types of facilities show inadequate, but slowly improving, numbers of physicians, physicists, dosimetrists, and technologists when compared with the level recommended by the Blue Book.
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 1989
Bilateral breast carcinoma treated with definitive irradiation.
From 1977 to 1987, 30 women were treated with definitive irradiation following breast-conserving surgery for bilateral carcinoma of the breast for a total of 60 treated breasts. Eleven women presented with concurrent bilateral carcinoma, and 19 women had sequential bilateral carcinoma. Pathologic axillary staging was performed in 51 of the 60 treated breasts. ⋯ An analysis of complications and cosmesis showed results similar to previously reported results for unilateral breast cancer. These results show that definitive irradiation following breast-conserving surgery for patients with bilateral breast cancer can technically be delivered with low complication rates and with acceptable survival and local control rates. Definitive irradiation should be considered as an acceptable alternative treatment to bilateral mastectomy for appropriately selected patients with concurrent or sequential bilateral early stage carcinoma of the breast.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 1989
Randomized Controlled Trial Multicenter Study Comparative Study Clinical TrialResults of a randomized trial comparing BCNU plus radiotherapy, streptozotocin plus radiotherapy, BCNU plus hyperfractionated radiotherapy, and BCNU following misonidazole plus radiotherapy in the postoperative treatment of malignant glioma.
In Brain Tumor Cooperative Group Study 77-02, eleven institutions randomized 603 adult patients with supratentorial malignant glioma to one of four treatment groups following surgery: conventional radiotherapy (6000 cGy in 30-35 fractions) + BCNU, conventional radiotherapy + streptozotocin, hyperfractionated (twice daily) radiotherapy (6600 cGy in 60 fractions) + BCNU, and conventional radiotherapy with misonidazole followed by BCNU. Data were analyzed for the total randomized population and for the 557 patients (86% with glioblastoma multiforme) who met protocol eligibility specifications (including confirmed histopathology on central review). Median survival was approximately 10 months following randomization. ⋯ Among non-glioblastoma patients, the misonidazole group appeared to have poor survival. Peripheral neuropathy was a dose-limiting toxicity with misonidazole. It is concluded that neither the addition of misonidazole nor hyperfractionated radiotherapy as given in this protocol offered any advantage over conventional radiotherapy plus either BCNU or streptozotocin for treatment of malignant glioma.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 1989
Dose fractionation and regeneration in radiotherapy for cancer of the oral cavity and oropharynx: tumor dose-response and repopulation.
In a retrospective study, local control of the primary tumor in 498 squamous cell carcinomas of the oral cavity and oropharynx was analyzed with respect to initial tumor volume, total dose after normalization for variations in fraction size, and to overall treatment time. Primary tumors were grouped into 4 sites, tongue (175), oral cavity including floor of mouth, faucial pillar, soft and hard palate and gingiva (210), tonsil (72) and buccal mucosa (41). Total doses of 60Co irradiation ranged from 30 Gy to 72 Gy, overall treatment times from 15 to 80 days and dose per fraction from 1.8 to 6 Gy. ⋯ Over the interval of about 30-55 days used in treating most of this series of patients, an increase of 60 cGy per day, on average, was required for a constant control rate. (2) The increase in dose was attributed to accelerated tumor clonogen growth rate. Such accelerated growth could be a major determinant of failure in protracted regimens. (3) The accelerated rate of regrowth was similar for all tumor sites and stages. (4) The dose for tumor control was relatively independent of variations in fraction size within a range of about 1.6 Gy to 3 Gy: the alpha/beta value in the linear quadratic isoeffect equation was at least 15 Gy. (5) Local control at the primary site required an average of about 3 Gy more for each increase in T stage. This increase most likely reflected an increased number of tumor clonogens, not a decreased tumor cell radiosensitivity. (6) The probability of control at the primary site was less likely if lymph nodes were positive, but this association was only shown to be statistically significant for primaries classified here as oral cavity and oropharynx, not tonsil, tongue or buccal mucosa. (7) After allowing for differences in treatment parameters, especially for heterogeneity in overall treatment times, tumor control probability increased steeply with increase in total dose. (8) A general principle of radiotherapy, at least for squamous carcinomas of head and neck, should be to deliver the desired fractionated dose regimen without unnecessary interruptions and in the shortest time compatible with no reduction in dose below that tolerated by the late-responding normal tissues.