Malcolm A. Bagshaw

Definitive Radiation Therapy of Carcinoma of the Prostate

The charts of 310 consecutive patients with localized prostatic carcinoma treated definitively with small-field external-beam irradiation were reviewed. The 5- and 10-year uncorrected actuarial survival rates for patients with disease limited to the prostate were 72 and 48%, respectively, compared to 48 and 30% in patients with palpable extracapsular extension. Patients for whom the interval between histological diagnosis and initiation of radiotherapy was less than one year had a significantly higher survival rate than those for whom this interval was longer. Severe symptoms which persisted beyond one year after treatment developed in 5%. Sexual potency was maintained in 70% of patients not hormonally manipulated following radiotherapy.

Carcinoma of the nasopharynx. Eighteen years' experience with megavoltage radiation therapy†

From 1956 through 1973, 82 patients with carcinoma of the nasopharynx received high dose megavoltage radiation therapy at Stanford University. The actuarial disease‐free (NED) survival was 62% at 5 years and 56% at 10 years. The NED survivals at 5 years for patients with T1, T2, and T3 lesions were 76%, 68%, and 55%, respectively. No T4 patients were salvaged, but two of 10 patients who presented with cranial nerve dysfunction were long‐term survivors. The degree of nodal involvement also had prognostic significance. Involved lymph nodes were successfully controlled in all instances when doses of at least 6500 rads were given. Initial treatment failed in 32 patients. In 24 (75%) this occurred within 18 months. Thirteen patients with initial recurrences in head and neck sites were retreated and three remain alive. Survival after retreatment ranged from 2 months to 10 years, with a median of 16 months. Although nearly one‐third (6/17) of the patients with local recurrences had initial T1 or T2 lesions, there have been no failures in patients treated for these early stages in the last 7 years. This may be attributed to the use of larger treatment fields. Likewise, prophylactic irradiation of the neck was always successful in preventing nodal disease if the primary site was controlled.

Patterns of spread of distant metastases in head and neck cancer

Ninety‐six (12.3%) of a total of 779 patients with head and neck cancer were found (clinically or at autopsy) to have distant metastases in the period from 1955 to 1967, in a study at the Division of Radiation Therapy, Stanford University School of Medicine. The study was confined to adults with epithelial tumors. All areas in the head and neck region were reviewed, except the paranasal sinuses, eye, ear, and thyroid gland. Metastases to the lungs, bone, and liver were the most common, but unexpected metastases to the heart, spleen, and gastrointestinal tract were frequently found. The most advanced primary tumors (T4) were most likely to have metastases. More than 50% of patients in whom the primary site was effectively controlled developed metastases. Forty patients of the 96 with metastases had an autopsy; further metastatic sites, not apparent clinically, were found in most of these patients.

Stereotaxic Radiosurgery for Brain Metastases; The Importance of Adjuvant Whole Brain Irradiation

Stereotaxic radiosurgery delivered from a modified 4 MV linear accelerator was used to treat 47 brain metastases in 27 patients at Stanford. Response was assessed in 41 lesions. Histopathologies included adenocarcinoma (24 lesions), renal cell carcinoma (9 lesions), melanoma (6 lesions), and squamous cell carcinoma (2 lesions). Follow-up ranged from 1.0-16.5 months, with a median of 5.0 months. Radiographic local control was achieved in 88% of the lesions. Three patients developed enlarging contrast-enhancing lesions in the radiosurgical field; one of these was biopsied and revealed necrosis with no viable tumor. Adjuvant whole brain irradiation (10 patients) was associated with regional intracranial control in 80% of patients. This was statistically superior (p = 0.0007) to the regional intracranial control rate achieved when radiosurgery alone was employed (6 patients). Most patients reported resolution of their neurologic symptoms, and were able to discontinue dexamethasone without impairment of neurologic function.

Prostate Specific Antigen after External Beam Radiotherapy for Prostatic Cancer: Followup

Between 1986 and 1989, 117 patients with pretreatment and serial posttreatment prostate specific antigen values received external beam radiotherapy at our hospital. Followup ranged from 0.6 to 5.9 years (mean 2.7). No patient had hormonal manipulation before distant recurrence. Biochemical relapse, defined as an increasing prostate specific antigen level after treatment, was observed in 44 patients. To date 30 of these 44 patients (68%) have had clinical relapse. The prognostic factors of advanced local stage, high Gleason score and high elevations of pretreatment prostate specific antigen values predicted for biochemical relapse and subsequent clinical failure. The interval between biochemical and clinical relapse was 156 +/- 46 days. Biochemical relapse is an important end point that can be used to determine the effect of treatment in prostatic cancer research.

LINEAR ACCELERATOR SUPERVOLTAGE RADIOTHERAPY. VII. CARCINOMA OF THE PROSTATE.

IN A COMPREHENSIVE survey, clinically evident carcinoma of the prostate was exceeded only by skin cancer as the most frequent malignant lesion in the male (1). In a review of available mortality statistics, Veenema et al. calculated that in 1962 prostatic cancer caused 14,000 deaths in the United States (2). In spite of this prevalence, primary treatment of this neoplasm by the radiotherapist has been curiously neglected. For example, the California study indicated that between 1942 and 1956 only 5 out of 2,492 cases of localized prostatic cancer were treated with irradiation. It is perhaps paradoxical that, since the first aggressive surgical approach to carcinoma of the prostate by Young in 1904 (3) with radical perineal prostatectomy, the urologists have made creditable advances in the treatment of this disease with nonsurgical technics. The introduction of endocrine therapy by Huggins in 1941 and interstitial radiation therapy with radioactive gold by Flocks and his coworkers in 1951 are important exa...

Bladder cancer: results of radiation therapy in 384 patients

Between 1957 and 1972, 384 patients with bladder cancers were treated initially with megavoltage radiation therapy. Actuarial five-year survival ranged from 35 to 42% for Stages A and B1 tumors, and was 35, 22 and 7%, respectively, for Stages B2, C and D carcinomas. Approximately 30-40% of deeply invasive tumors confined to the bladder can be controlled with radiation therapy alone, directed solely to the bladder itself.

Long-term effects of external radiation on the pituitary and thyroid glands

Chronic damage following external irradiation of the normal pituitary and thyroid glands, delivered incidentally during radiotherapy of neoplasms of the head and neck may be more common than has been appreciated in the past. A case of a child who developed pituitary dwarfism 5Vi years after radiation therapy had been delivered for an embryonal rhabdomyosarcoma of the nasopharynx is described. A review of similar cases from the literature is presented. Likewise, external irradiation of the normal thyroid gland produces a spectrum of radiation‐induced syndromes. Clinical damage to the pituitary and thyroid glands is usually manifested months to years after treatment and is preceded by a long subclinkal phase. A careful exclusion of these glands from radiation treatment fields is recommended whenever possible. An early detection of endocrine function abnormalities in patients receiving radiation to these glands is desirable, since appropriate treatment may prevent the late deleterious effects of external irradiation of the pituitary and thyroid glands.

Stanford University institutional report. Phase I evaluation of equipment for hyperthermia treatment of cancer

From September 16, 1981, through April 4, 1986, a total of 21 radiative electromagnetic (microwave and radiofrequency), ultrasound and interstitial radio-frequency hyperthermia applicators and three types of thermometry systems underwent extensive phantom and clinical testing at Stanford University. A total of 996 treatment sessions involving 268 separate treatment fields in 131 patients was performed. Thermal profiles were obtained in 847 of these treatment sessions by multipoint and/or mapping techniques involving mechanical translation. The ability of these devices to heat superficial, eccentrically located and deep-seated tumours at the major anatomical locations is evaluated and the temperature distributions, acute and subacute toxicities, and chronic complications compared. Average measured tumour temperatures between 42 degrees C and 43 degrees C were obtained with many of the devices used for superficial heating; average tumour temperatures of 39.6 degrees C to 42.1 degrees C were achieved with the three deep-heating devices. When compared to the goal of obtaining minimum tumour temperatures of 43.0 degrees C, all devices performed poorly. Only 14 per cent (118/847) of treatments with measured thermal profiles achieved minimum intratumoural temperatures of 41 degrees C. Fifty-six per cent of all treatments had associated acute toxicity; 14 per cent of all treatments necessitated power reduction resulting in maximum steady-state temperatures of less than 42.5 degrees C. Direct comparisons between two or more devices utilized to treat the same field were made in 67 instances, including 19 treatment fields in which two or more devices were compared at the same treatment session. The analyses from direct comparisons consistently showed that the static spiral and larger area scanning spiral applicators resulted in more favourable temperature distributions. Three fibreoptic thermometry systems (Luxtron single channel, four channel and eight channel multiple [four] probe array), the BSD Bowman thermistor system and a thermocouple system were evaluated with respect to accuracy, stability and artifacts. The clinical reliability, durability, and patient tolerance of the thermometry systems were investigated. The BSD Bowman and third generation Luxtron systems were found clinically useful, with the former meeting all of our established criteria.

External beam radiation therapy of primary carcinoma of the prostate

During the past 10 years, some 15 publications have appeared in the English literature on the definitive radiotherapy of prostatic cancer. The long‐term followup required for rational assessment of the treatment of prostatic cancer is not yet available for most of these studies. However, in the Stanford series, the direct disease‐free survival at 5 years for patients with disease localized to the prostate is 70%; at 10 years, 42%. The direct disease‐free survival at 5 years for patients with extracapsular extension is 36%, and at 10 years, 29%. Recently, mapping of potential lymph node metastases has been studied by several authors. Early results of extended‐field irradiation required for regional treatment are presented.