Theodore C.M. Lo

Single-dose electron beam irradiation in treatment and prevention of keloids and hypertrophic scars

Low megavolt electron beam irradiation was used on 354 sites in 199 patients at the Lahey Clinic either for palliation of symptomatic hypertrophic scars or as post-operative irradiation in an attempt to prevent formation or recurrence of hypertrophic scars. Electron energies used ranged from 1.5 to 3.5 MeV. The median age of the 59 male patients was 22 years and of the 140 female patients, 35 years. All patients had at least one follow-up visit, and the median follow-up was 35 months. Of the 294 sites treated for the first time, 272 (93%) were irradiated with a single fraction with a skin dose ranging from 2 to 20 Gy. Of the 85 sites in 63 patients without excision of symptomatic hypertrophic scars, single-dose electron beam irradiation was of clinically significant value in only 41 sites (48%). No patients have been treated without surgical excision since 1973. Because of a history of formation of hypertrophic scars elsewhere in the body, 13 patients with 19 incisions were treated prophylactically after operation for other diseases. All sites were irradiated with single doses ranging from 8 to 20 Gy, and hypertrophic scars did not subsequently develop in any patient. Altogether, 119 patients with 174 sites were irradiated after surgical excision of hypertrophic scars to prevent recurrence; 168 sites (97%) received single-fraction irradiation, and 161 received a dose of 8 Gy or greater, up to 15 Gy. No statistically significant differences were observed in complete success rates, ranging from 82 to 90% with doses of 9 Gy or greater.(ABSTRACT TRUNCATED AT 250 WORDS)

Radiotherapy for Kaposi's sarcoma

Between 1954 and 1976, 60 patients with Kaposis sarcoma were treated in the Department of Radiotherapy of the Lahey Clinic Foundation at the High Voltage Research Laboratory of Massachusetts Institute of Technology. Only 2 patients were free of clinical disease in the lower extremities at the time of initial presentation, and 40 patients (69%) had cutaneous lesions involving areas extending above the knees. Eight patients (13%) also presented with mucous membrane involvement in addition to skin disease.

Brain necrosis after radiotherapy for primary intracerebral tumor.

Radiotherapy is a standard postoperative treatment for cerebral glioma. We have observed the onset of symptoms related to brain necrosis, as opposed to recurrent tumor, in surviving patients. This has been manifest as dementia with a computed tomographic pattern of low density in the frontal lobe uninvolved with tumor, but within the field of radiotherapy. Two patients presented with mass lesions also unrelated to recurrent tumor. We question the necessity of full brain irradiation and suggest that radiotherapy techniques be altered to target the tumor and not encompass the entire brain.

Radiation therapy for heterotopic ossification.

Heterotopic ossification is a common complication after bone and joint surgery. If the disease progresses, it may cause pain and disability, eventually defeating the purpose of surgery in the first place. Today, prophylactic treatment is indicated after surgery. Both nonsteroidal antiinflammatory drugs and radiation therapy are effective. Radiation therapy is associated with fewer side effects and is preferred. Single-dose postoperative irradiation has been found to be as effective as fractionated radiation therapy.

Intraluminal low-dose rate brachytherapy for malignant endobronchial obstruction☆

From October 1985 through October 1989, 87 patients underwent 105 intraluminal brachytherapy treatments for endobronchial or endotracheal malignant tumors. Low-dose rate iridium-192 seeds were used. Of the 60 patients treated for primary lung carcinoma, 52 patients (87%) had previously received full-course external beam radiotherapy to the tumor sites. Ten patients were treated for symptomatic metastatic disease, and one patient had extension of tumor into the trachea from carcinoma of the cervical esophagus. Clinical or bronchoscopic improvement was noted in 42 patients (59%). No significant difference in the response rate was observed between various types of tumor. Patients who were treated with a radiation dose larger than 2500 cGy at a 2 cm radius had a significantly greater response rate (77%) than patients treated with a dose less than 2500 cGy (38%) (p = 0.001). A trend toward better results was apparent in patients who had undergone Nd:YAG laser bronchoscopy in the 2 weeks before brachytherapy. The treatments were well tolerated, and the incidence of serious complications was low and acceptable.

Glucocorticoid Dependency as A Prognostic Factor in Radiotherapy for Cerebral Gliomas

Records of 76 consecutive patients treated with radiotherapy for cerebral gliomas were reviewed. Eleven patients had no tissue diagnosis, and their outcome was comparable to that of patients with glioblastoma. Patients with other histologic diagnoses had much better results. Among the entire study population, the most important prognostic factors included age and histologic grade. Even with stratification by histologic grade and age, glucocorticoid (steroid) dependency was a reliable prognostic indicator in terms of survival. Fifteen of the 47 patients (32%) who were less steroid dependant are still alive with a median survival time of 29 months. Among the 29 patients who were heavily dependant on steroids during the course of radiotherapy, the median survival time was 5 months with only 2 patients (7%) still alive.

Megavolt Electron Irradiation for Localized Mycosis Fungoides

A retrospective analysis was carried out to evaluate the effectiveness of small field megavolt electron irradiation for localized mycosis fungoides. Only local field electron beam therapy was employed for limited disease reserving total skin electron irradiation for multiple lesions or diffuse disease covering at least 25 per cent of the entire body surface. Of the 14 patients with limited disease treated between 1964 and 1973 with the local field technique, 10 patients (71 per cent) are alive without evidence of disease at a minimum of 5 years. In contrast, of 200 patients with extensive cutaneous disease who received total skin electron irradiation, only 16 (8 per cent) were considered cured. It is concluded that early localized mycosis fungoides is potentially curable, and that limited field electron beam therapy with a relatively low total dose is adequate to obtain excellent response.

Multiple Distinct Intracranial Tumors: Association of Pinealoma and Craniopharyngioma Case Report

We report the case of a patient with multiple primary brain neoplasms. A pinealoma was treated with radiotherapy and surgical resection in 1983. In 1987, a craniopharyngioma was resected surgically. Various possible determinants of multiple brain tumors have been described in the literature and are discussed. The possibility of an unknown underlying pathologic mechanism predisposing to multiple malignancies must be considered, but we are unable to conclude that this particular occurrence is more than a random chance finding.

Megavolt Electron Irradiation in the Treatment of Recurrent Carcinoma of the Breast on the Chest Wall

Low megavolt electron beam therapy was used to treat 68 women and one man with recurrent carcinoma of the breast on the chest wall. Photon irradiation had been used previously in 53 patients. Of the 63 patients who survived 2 months or longer after electron irradiation, 59 (94%) achieved a complete response. Persistent radiation ulcers developed in only 2 patients (3%). No other late radiation complications were observed. Nineteen patients (28%) survived 3 years after electron irradiation, with a median survival of 54 months. In this group, disease eventually recurred in all patients who received a calculated NSD of less than 1 400 ret; no disease recurred in the patients who received doses greater than 1 400 ret. It is concluded that megavolt electron irradiation is effective in the treatment of chest wall recurrence from carcinoma of the breast and is safe even in patients who have had a previous course of photon irradiation.

Radiotherapy for kaposi's sarcoma

Between 1954 and 1976, 60 patients with Kaposis sarcoma were treated in the Department of Radiotherapy of the Lahey Clinic Foundation at the High Voltage Research Laboratory of Massachusetts Institute of Technology. Only 2 patients were free of clinical disease in the lower extremities at the time of initial presentation, and 40 patients (69%) had cutaneous lesions involving areas extending above the knees. Eight patients (13%) also presented with mucous membrane involvement in addition to skin disease. Twenty-one patients were treated only with megavoltage electrons during the initial course of radiotherapy, and 12 patients were treated with supervoltage photons alone. The remaining 27 patients were treated with a combination of electrons and photons; in 17 patients, the same tumor sites were irradiated with both modalities. Eleven patients received whole-body surface electron irradiation. The choice of treatment modalities was based on the extent and distribution of cutaneous disease and depth of the lesions. The overall response rate was 93% after a single fractionated course of radiotherapy. Twenty-five patients achieved complete regression and 18 were in remission for 2-13 years. Response rates were also analyzed with respect to the three subgroups in terms of treatment modalities. A single dose of 800 to 1200 rads or its equivalent was required to control local cutaneous lesions. Widespread visceral metastasis was the most common cause of failure and death; the incidence of second malignancies was increased. Trial of systemic chemotherapy and immunotherapy would seem to be a reasonable therapeutic adjunct.