Peter J. Fitzpatrick

Half body radiotherapy

“Necessity is the mother of invention and serendipity the handmaiden”. The Toronto philosophy in radiotherapy has, for several decades, been one of large volume irradiation in preference to the more classical teaching of “excisional therapy” using small volumes and high dose. In this respect our pattern of practice has been different and unique. However, it was based on critical retrospective reviews of “patterns of failure.” In most sites where an improvement in survival was demonstrated, this was due to increased volume irradiated rather than increased dose; care was taken to exclude other variables, e.g., stage or grade, which might have been more responsible for any improvement than the therapy itself.

Role of radiation therapy in localized non-Hodgkin's lymphoma*

Relapse occurs in 50% of patients receiving radiation for clinical stage (C.S.) I and II nodal and extranodal non-Hodgkins lymphoma (N.H.L.). Prior to the introduction of intensive chemotherapy those failing primary control with irradiation and most of those who relapsed died of their disease with a resultant overall mortality of 50%. An analysis of Princess Margaret Hospital results with radiation for C.S. I and II N.H.L. between January 1967 and December 1978 revealed that tumour bulk, age, stage and histology were of independent prognostic significance. It was possible to group patients using combinations of these attributes so that each group encompassed only patients with similar outcomes. Such prognostic groups were identified separately within the low grade and the intermediate plus high grade categories of the Working Formulation. Patients with a high probability of cure with radiation were so defined. Also those patients in whom chemotherapy would be optimal initial therapy were also defined. Such patients were in the intermediate plus high grade histology groups. Thirty percent of all patients with low grade histology lymphoma had an actuarial survival of 83%, and relapse-free rate of 63% at 10 years. By implication, approximately 20% of all patients with these histologies seen at the Princess Margaret Hospital for the same time period achieved prolonged relapse-free survival by localized therapy. This is at variance with the implications of staging from studies where laparotomy and multiple bone marrow biopsies have been used. Such aggressive staging procedures suggest truly localised disease in only 5-6% of patients with low grade lymphoma. A significant relationship between radiation dose and disease control was demonstrated only for patients with intermediate and high grade lymphoma of medium or large bulk. A minimum tumour dose of 30 Gy was required for optimal local control with radiation.

Primary radiation therapy for juvenile nasopharyngeal angiofibroma.

Evidence is presented of the effectiveness and relative lack of serious toxicity of external beam megavoltage radiation therapy (RT) as primary treatment for juvenile nasopharyngenl angiofibroma. The importance of careful radiological evaluation of tumor extent prior to irradiation is stressed, and only moderate dose RT is required.

Basal and squamous cell carcinoma of the eyelids and their treatment by radiotherapy

We report 1,166 tumors of the eyelids that were treated by single or fractionated exposures to doses of 20-60 Gy. The five year tumor control rate was 95% for basal cell and 93.3% for squamous cell carcinoma. Irradiation was equally successful in primary cases and in those recurrent following surgery. Recurrence following irradiation was managed by surgery or further irradiation. The cosmetic and functional results were generally excellent and readily accepted by most patients. The overall complication rate was 9.6% with fewer than one-half rated as serious; these problems mainly occurred with large tumors that had destroyed normal tissues. In only 14 (1.2%) patients was death related to the tumor. Approximately one-half of the patients received a dose of 35 Gy in five daily fractions, one-quarter, 20 to 22.5 Gy in a single exposure and the others with larger tumors 42.5-60 Gy in 10 to 30 exposures in two to six weeks. Radiotherapy is a safe and cost effective treatment for eyelid tumors.

A management approach to incompletely excised basal cell carcinomas of skin.

There were 187 incompletely resected basal cell carcinomas (BCC) of skin referred to the Princess Margaret Hospital between 1970 and 1985. Median age at presentation was 62 years. The commonest location of these lesions was in the head and neck region (93%). One hundred twenty lesions were immediately treated: 119 were irradiated and 1 was excised. The remaining 67 lesions were managed expectantly. Follow-up time for the entire population ranged from 1 month to 17 years, with a median time of 2.7 years. The 5-year probability of remaining relapse-free in the group immediately treated was 91% versus 61% if managed expectantly (p = 0.0001). If only lateral margins were positive, the crude probability of local failure was 3/18 (17%), versus 9/27 (33%) if the deep margins were involved (p = 0.2). Once relapse occurred in the group of lesions treated expectantly, 17/20 (85%) of these relapses were salvaged by either radiation or surgery. The 10-year actuarial probability of local control for the lesions immediately treated and observed were similar: 92% and 90%, respectively (p = 0.5). An economic analysis revealed that immediate radiation treatment saved the health system only

Outcome analysis of localized gastrointestinal lymphoma treated with surgery and postoperative irradiation.

223.00 per patient. Since there is no difference in the ultimate local control between these two approaches, and these elderly patients may be spared the morbidity of unnecessary treatments, it is suggested that a policy of observation may be adopted for basal cell carcinomas of skin which have been incompletely excised.

Cervical metastases from an unknown primary tumor.

One hundred thirteen patients with localized gastrointestinal lymphoma treated by surgery and postoperative irradiation between 1967 and 1985 were reviewed. At 15 years, actuarial survival of this group was 40.6%, with a cause-specific survival of 69.2% and a relapse-free rate of 64%. Two-thirds of relapses occurred at distant sites. In Stage IA and IIA patients with no residuum or with positive resection margins, (N = 90) only site of involvement and stage predicted for relapse. Age, histologic subtype group, and depth of bowel wall invasion did not affect relapse risk. In the very favorable group (Stage IA, IIA, no residuum or microscopic residuum), 8.4% of patients with stomach lymphoma relapsed compared to 25% of patients with small bowel lymphoma. The risk of early relapse was higher in those with Stage IIA small bowel lymphoma than those with Stage IA small bowel lymphoma. We continue to recommend adjuvant abdominal irradiation for patients with Stage IA, IIA completely resected stomach lymphoma and Stage IA completely resected small bowel lymphoma. We recommend combined modality therapy for patients with completely resected Stage IIA small bowel lymphoma and all other localized gastrointestinal lymphoma where visible residual disease is present.

Intraocular Lymphoma: Report of Three Cases and Review of the Literature

Treatment of 233 patients with metastatic cancer in the neck and an unknown primary tumor was studied. The five-year crude survival rate was 18%, but among patients with disease limited to the upper and midneck irradiated to 4,500 rads in four weeks, the rate was 44%. Optimum irradiation consists of 5,500 rads in five weeks delivered via supervoltage technique to a volume of tissue extending from the base of the skull to the clavicle and reaching the midline. This treats metastases in the neck and the most common primary tumor sites. For patients with metastatic disease low in the neck, prognosis is poor; palliation is obtained with 2,000 rads in one week.

The radiotherapy of nasopharyngeal angiofibroma.

Three cases of intraocular lymphoma are presented. One patient had only ocular involvement, one had involvement of the eye and central nervous system, and in the third patient, ocular lymphoma developed 1 year after the diagnosis of a systemic lymphoma. One patient died before treatment could be initiated, but the other two patients responded well to local radiotherapy. Only one patient who received radiation to both eyes and the whole brain, followed by systemic chemotherapy, remains alive 4 years after diagnosis. Eighty-seven cases of intraocular lymphoma reported in the literature are reviewed. Only 16.7% of cases involved the eyes alone without central nervous system or systemic disease. In more than one-half of the cases (59.7%), the eye was the primary site of involvement. Craniotomy or enucleation was required for diagnosis in 52.7% of patients, and diagnosis frequently followed a significant period of delay during which time patients were treated unsuccessfully for uveitis or iritis. Death for most patients was due to progressive central nervous system involvement. Therefore, we recommend combined modality therapy with radiation to the whole brain and both eyes, followed by systemic chemotherapy with or without intrathecal medications.

Half-Body Radiotherapy in the Treatment of Canine Lymphoma

Between 1946 and 1971, 39 patients including 3 females with nasopharyngeal angiofibroma were seen at Princess Margaret Hospital, Toronto. Bone destruction with extension into the air sinuses, orbit, and cranium was seen in 30 of 38 patients. The tumor and its many ramifications are best detected by coronal tomography. Radiotherapy consisting of 3,000 rads in three weeks leads to thrombosis, fibrosis and tumor regression, although two years may pass before it finally disappears. Following irradiation, only 6 patients suffered tumor recurrence and 4 of these required radiotherapy before the lesion finally disappeared.