External beam radiotherapy and hyperthermia in the treatment of patients with locally advanced prostate carcinoma.

BACKGROUND: The current study was conducted to evaluate the combination of external beam radiation therapy and hyperthermia in the treatment of patients with locally advanced prostate carcinoma. METHODS: Twenty-six patients were treated on a Phase I/II protocol between June 1990 and April 1993. The median age of the patients was 69 years. Nine patients had well differentiated adenocarcinoma, ten patients had moderately differentiated adenocarcinoma, and six patients had poorly differentiated adenocarcinoma. All patients had American Urologic Society Stage C2-D1 adenocarcinoma. The median pretreatment prostate specific antigen (PSA) level was 29 ng/mL (range, 6-104 ng/mL). All patients received external beam radiation therapy using a four-field technique. The median radiation dose was 6,800 centigrays (cGy) given in 200-cGy fractions. Hyperthermia was administered concurrently with radiation therapy to temperatures of 42.5 degrees C for 30 minutes using a transrectal ultrasound applicator with 3 thermometry probes, given as either a single treatment (9 patients) or as two treatments (17 patients). Overall survival (OS) and biochemical no evidence of disease (bNED) status were calculated using Kaplan-Meier analysis. A consensus conference definition of PSA failure was used. The Cox proportional hazards model was used for multivariate analysis. The median follow-up for all patients was 71 months. RESULTS: The median time to PSA nadir was 15 months with a median PSA nadir value of 1.0 ng/mL. The median and 5-year OS was 88 months and 73%, respectively, and the median and 5-year bNED survival was 36 months and 35%, respectively. Multivariate analysis revealed only the pretreatment PSA level (P = 0.03) and the PSA nadir reached (P < 0.01) to be significant predictors of bNED survival. The duration of hyperthermia therapy showed a trend toward significance for OS (P = 0.06). CONCLUSIONS: The current Phase I/II protocol evaluating the combination of prostate hyperthermia and external beam radiation therapy for the treatment of patients with locally advanced prostate carcinoma suggests prostate hyperthermia to be feasible with no apparent significant increased toxicity, although there was no significant improvement in treatment outcome when compared with other studies reported in the literature evaluating external beam radiation therapy with or without androgen suppression. However, further investigation into the duration as well as the temperature of the hyperthermia with a greater number of patients is warranted.

Chemotherapy alone compared with chemotherapy plus radiotherapy for localized intermediate- and high-grade non-Hodgkin's lymphoma.

BACKGROUND: Patients with clinically localized, intermediate- or high-grade non-Hodgkin's lymphoma usually receive initial treatment with a doxorubicin-containing regimen such as cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). Pilot studies suggest that eight cycles of CHOP alone or three cycles of CHOP followed by involved-field radiotherapy are effective in such patients. METHODS: We compared these two approaches in a prospective, randomized, multi-institutional study. The end points were progression-free survival, overall survival, and life-threatening or fatal toxic effects. Two hundred eligible patients were randomly assigned to receive CHOP plus radiotherapy, and 201 received CHOP alone. RESULTS: Patients treated with three cycles of CHOP plus radiotherapy had significantly better progression-free survival (P=0.03) and overall survival (P=0.02) than patients treated with CHOP alone. The five-year estimates of progression-free survival for patients receiving CHOP plus radiotherapy and for patients receiving CHOP alone were 77 percent and 64 percent, respectively. The five-year estimates of overall survival for patients receiving CHOP plus radiotherapy and for patients receiving CHOP alone were 82 percent and 72 percent, respectively. The adverse effects included one death in each treatment group. Life-threatening toxic effects of any type were seen in 61 of 200 patients treated with CHOP plus radiotherapy and in 80 of 201 patients treated with CHOP alone (P=0.06). The left ventricular function was decreased in seven patients who received CHOP alone, whereas no cardiac events were recorded in the group receiving CHOP plus radiotherapy (P=0.02). CONCLUSIONS: Three cycles of CHOP followed by involved-field radiotherapy are superior to eight cycles of CHOP alone for the treatment of localized intermediate- and high-grade non-Hodgkin's lymphoma.

Dose profiles in the region of abutting photon and electron fields in the irradiation of head and neck tumors.

In the treatment of head and neck tumors, after excluding the spinal cord from the primary photon beam, en face electron fields are employed to boost the dose to the tissues overlying the spinal cord. The electron fields are "hot-matched" on skin with the posterior edges of the photon fields irradiating the primary tumor. The purpose of this study is to measure the dose distribution in the "hot" matched region between the photon and the en face electron fields. Using film dosimetry, we measured the dose distributions at depths of 1 cm and 3 cm in the junction of the abutting photon (4 MV) and electron (9 MeV) fields for a hot-match setup. Two photon field setups were studied: (1) laterally opposed and, (2) shallow (5 degrees) right and left anterior oblique fields, a configuration sometimes used to avoid treating through the shoulders. To investigate the changes in dose distributions due to setup uncertainties, we also measured dose profiles at the same two depths using a 2 mm overlap and a 2 mm gap between the electron and photon fields. For a perfect hot-match, the dose profile across the junction at 1 cm depth consists of "hot-spots" on both sides of the junction. The minimum and maximum doses across the junction are 15% and 58%, respectively, above the prescribed dose for a parallel opposed setup and 35% and 54%, respectively, for the angled setup. At 3 cm depth, a 10% "cold spot" is observed in the electron field proximal to the junction while a 50% 'hot spot' is observed in the photon field for the opposed lateral setup. With the lateral fields angled 5 degrees anteriorly, hot spots are observed on both sides of the junction. The minimum and maximum doses are 23% and 54%, respectively, above the prescribed dose. With the right and left anterior oblique fields, a 2 mm overlap of the en face electron field with the ipsilateral photon field resulted in a 72% and 65% hot spot at 1 cm and 3 cm depths, respectively, in the photon field adjacent to the junction. A 2 mm gap still resulted in about a 45% hot spot in the same region at both depths. Clinically, if dose to the overlying tissue of the spinal cord is of primary concern, our measurements suggest that 80% normalization in the electron boost, together with a slight angulation of the photon fields would ensure adequate dose to the overlying tissues. If dose inhomogeneity to the superficial tissues is critical in the electron irradiation, 90% dose normalization in the electron boost, together with laterally opposed photon fields would be preferred. The clinical decision can only be made on a patient-by-patient basis.

The use of stereotactic radiosurgical boost in the treatment of medulloblastomas.

PURPOSE: Starting in 1992, we began using a stereotactic radiosurgical (SRS) boost for the treatment of medulloblastomas. Four patients ranging in age from 7 to 42 years old have since been treated and are the subject of this retrospective study. METHODS AND MATERIALS: All patients were initially treated with a maximally debulking surgery and external beam radiotherapy, which were then followed by a stereotactic radiosurgical boost using a modified 6 MeV linear accelerator. Radiosurgical boost doses ranged from 4.50 to 10.0 Gy. Target volumes ranged from 1.1 to 8.1 cc. The procedure was well tolerated with minimal acute toxicities. RESULTS: All four patients are alive without evidence of recurrence (at 8 to 35 months). Acute nausea and vomiting was elicited during the radiosurgical procedure in the first patient treated. We have since begun premedicating patients with antiemetics or treating under general anesthesia. Late complications consisted of panhypopituitarism in one patient, which was thought to be attributable to the previous course of whole-brain radiotherapy. We have not observed any incidence of radionecrosis in this small cohort of patients. CONCLUSIONS: Our preliminary results with the use of radiosurgery for medulloblastomas are optimistic, and we would like to suggest the inclusion of a radiosurgery boost in future clinical trials for treatment of this disease.

Vulvar carcinoma.

PURPOSE: Controversies exist regarding the use of radiation therapy in the treatment of vulvar carcinoma. A retrospective review was performed to evaluate our institution's experience with surgery and radiation for this disease. METHODS AND MATERIALS: The medical records of 47 patients treated for squamous cell carcinoma of the vulva at our institution (1974-1992) were reviewed for TNM stage (AJCC criteria), treatment modality, and associated 5-year local control and survival based on Kaplan-Meier analysis. RESULTS: Twenty-eight patients (60%) presented with Stage I and II disease and their 5-year survival was 69%. Stage III patients accounted for 12 (25%) of the patients and their 5-year survival was 73%. Seven patients presented with Stage IV disease and five died within 13 months of diagnosis after predominantly palliative therapy. The 40 patients with Stages I, II, and III disease were treated aggressively and were further evaluated for treatment-modality-associated survival and local control. Radiation therapy was used as primary treatment in nine patients, of whom seven were treated with radiation alone and two were treated postoperatively after wide excision. Surgery alone was performed in 31 patients consisting of either radical vulvectomy (20 patients) or wide excision (11 patients). When comparing outcomes of radical vulvectomy vs. radiation therapy, we noted that the 5-year actuarial survivals were comparable (74% for either modality), despite the presence of more favorable prognostic factors in the group treated with radical vulvectomy. Patients treated with wide excision alone had a trend for a poorer 5-year actuarial survival (51%) and local control (50%). CONCLUSIONS: Radical vulvectomy offers good locoregional control and survival. This retrospective review further supports the use of radiation therapy with conservative surgery as an alternative treatment option for patients with vulvar carcinoma treated with curative intent. In contrast, the use of wide excision alone should be performed with caution due to a higher locoregional failure rate. The role of appropriately prescribed radiation therapy should be further investigated in prospective clinical trials.

The use of gold foil wrapping for radiation protection of the spinal cord for recurrent tumor therapy.

PURPOSE: The development of a technique to provide sufficient radiation protection to previously irradiated spinal cord in such a manner that interstitial brachytherapy can be conducted after resection of a recurrent tumor and decompression of the cord. METHODS AND MATERIALS: A technique was developed that uses multiple layers of gold foil that are applied around the thecal sac and nerve root sleeves to produce an enveloping radiation shield after resection of recurrent tumor. Once the layers of gold foil are in place, interstitial I125 seeds are permanently placed in the bed of the tumor resection to prevent any recurrence from microcellular disease. The technique is described and its application in the case of a 28-year-old with a third recurrence of chondrosarcoma after external fractionated radiation therapy at the second to the fourth thoracic segments is reviewed. RESULTS: This technique has been used in this first patient. An additional tumor dose of 120.0 Gy was delivered to the tumor bed while the spinal cord was calculated to receive only 1% of the dose over the life span of the implant. To date, this dose of radiation has prevented tumor recurrence for more than 18 months of follow-up. CONCLUSION: This technique of multiple layers of gold foil shielding over the spinal cord and nerve roots has the potential to be a useful tool for the shielding of a previously irradiated spinal cord in the setting of resection of recurrent tumor. It may also have a wider application to a number of other radiosensitive tumors where interstitial brachytherapy may be useful to provide additional treatment after external fractionated radiation therapy.

Clinical radiation nephropathy.

An analysis of the normal tissue effects of irradiation of the kidney is presented. Various clinical syndromes resulting from treatment are described as well as the potential cellular basis for these findings. Effects of concurrent and/or sequential treatment with irradiation and various chemotherapeutic agents are discussed and the impact of these agents on toxicity presented. Adverse consequences of renal treatment in the child is described and possible radiation effects on so-called compensatory hypertrophy following nephrectomy presented. Renal consequences described to date of bone marrow transplantation programs utilizing irradiation are also presented. The necessity of a dose-volume histogram analysis approach to analyzing renal toxic effects in patients followed for long (> 10 year) periods is essential in developing accurate guidelines of renal tolerance.

Preliminary clinical experience with linear accelerator-based spinal stereotactic radiosurgery.

A prototype device called an extracranial stereotactic radiosurgery frame was used to deliver stereotactic radiosurgery, with a modified linear accelerator, to metastatic neoplasms in the cervical, thoracic, and lumbar regions in five patients. In all patients, the neoplasms had failed to respond to spinal cord tolerance doses delivered by standard external fractionated radiation therapy to a median dose of 45 Gy (range, 33-65 Gy/11-30 fractions). The tumors were treated with single-fraction stereotactic radiosurgery with the spinal stereotactic frame for immobilization, localization, and treatment. The median number of isocenters was one (range, one to five) with a median single fraction dose of 10 Gy (range, 8-10 Gy) with median normalization to 80% isodose contour (range, 80-160%). There has been a single complication of esophagitis to date from radiosurgery of a tumor involving the C6-T1 segments; the esophagitis resolved with medical therapy. Median follow-up in this group of patients has been 6 months (range, 1-12 mo). To date, there has been no radiographic or clinical progression of the treated tumor in any patient. Two patients have died from systemic metastatic disease. In the three surviving patients, there has been computed tomographic- or magnetic resonance-documented regression of the treated tumor with a decrease of thecal sac compression with a median follow-up of 6 months (range, 3-14 mo). These five patients represent the first clinical application of stereotactic radiosurgery in the spine. The results suggest that extracranial radiosurgery may be suitable for the treatment of paraspinal neoplasms after external fractionated radiation therapy, even in the face of spinal cord compression.

Clinical hyperthermia with a new device: the current sheet applicator.

PURPOSE: The current sheet applicator (CSA) is a newly developed microwave hyperthermia device. Advantages over commercial microwave applicators include its small size and high ratio of heating area to physical aperture area. These physical characteristics make the CSA excellent for heating constricted areas and allow the use of arrays of CSAs over large surfaces. This study examines the clinical efficacy of the CSA for heating superficial malignant tumors. METHODS AND MATERIALS: From December 1989 through October 1991, 19 patients with recurrent or metastatic superficial malignant tumors were treated once or twice weekly to 30 hyperthermia fields using one to four CSAs. Each field received from one to four hyperthermia treatments for a total of 74 treatments. The treatment objective was to elevate the tumor temperature to a minimum of 42.5 degrees C for 30 min (2 patients) or 60 min (17 patients). Intratumor temperatures were measured with percutaneous fiberoptic thermometry probes. All patients received concurrent fractionated radiation therapy with total dose ranging from 20 to 65 Gy (median 46 Gy). Seventeen of the 30 fields had been previously irradiated to a median dose of 50 Gy. RESULTS: Mean values for the maximum temperature, average temperature, and minimum temperature were 43.6 degrees C +/- 1.0, 42.2 degrees C +/- 1.4, and 41.0 degrees C +/- 1.5, respectively. Mean values for T50 and T90 were 42.2 degrees C +/- 1.1 and 41.0 degrees C +/- 1.3, respectively. The overall response rate for all assessable fields was 96%. Only Only three responding tumors have progressed with a median follow-up period of 6 months. Treatment related morbidity was generally mild and self-limited. CONCLUSION: The CSA is a promising new microwave hyperthermia device capable of heating superficial tumors to therapeutic temperatures. When used in combination with radiotherapy, response rates are excellent without excessive toxicity.

Radiation-induced angiosarcoma of the breast. Case report and review of the literature.

Angiosarcoma is a rare, highly malignant soft tissue sarcoma that sometimes occurs in the breast as a late sequela of treatment for breast cancer. The conventional treatment for radiation-induced angiosarcoma is surgery, which is associated with a poor overall prognosis. We report a case of radiation-induced angiosarcoma of the intact breast that occurred 6 years after breast conservation therapy. Simple mastectomy was performed; however, rapid chest wall recurrence of angiosarcoma ensued. After salvage therapy with combined radiotherapy and hyperthermia, the patient has been disease-free for more than 3 years.

Interstitial irradiation versus interstitial thermoradiotherapy for supratentorial malignant gliomas: a comparative survival analysis.

PURPOSE: To compare the survival of two groups of patients with supratentorial malignant gliomas who were treated on two sequential protocols with either interstitial thermoradiotherapy or with interstitial irradiation without hyperthermia. METHODS AND MATERIALS: Between 1988-1992, patients with anaplastic astrocytoma or glioblastoma multiforme were treated at the University of Arizona on a Phase I/II protocol of interstitial thermoradiotherapy with ferro-magnetic seeds. The treatment protocol consisted of debulking surgery, a course of external beam radiotherapy and hyperthermia given immediately before and after brachytherapy. The survival of patients so treated was compared with that of a similar group of patients treated with interstitial brachytherapy alone at the Barrows Neurological Institute between 1982-1990. RESULTS: Twenty-five patients with primary tumors treated at the time of initial presentation with thermoradiotherapy were compared with a control group of 37 patients treated with interstitial brachytherapy alone. All primary patients were followed for a minimum of 34 months post implant. Multivariate analysis based on proportional hazards models showed that hyperthermia (p = 0.027), patient age (p < or = 0.00001) and histology (anaplastic astrocytoma vs. glioblastoma multiforme, p = 0.0017) were the only factors significantly associated with survival in this data set. From the fitted model, the hazard of dying when treated with hyperthermia was .53 times (95% confidence intervals 0.29-0.94) than that of the control group. In addition, we treated a small group of patients with recurrent tumors (13 with brachytherapy alone, and eight with thermoradiotherapy) and found no survival difference (p = 0.62). CONCLUSION: Within the constraints of the selection factors and the different treatment parameters used in these studies, we conclude that an interstitial thermoradiotherapy boost confers a statistically significant survival benefit to patients with primary high grade gliomas when compared to interstitial brachytherapy alone.

A comparison of survival between radiosurgery and stereotactic implants for malignant astrocytomas.

The purpose of this paper is to compare the survival of three groups of patients with high grade supratentorial gliomas who were treated on three sequential protocols with surgical resection, external beam fractionated radiotherapy and a boost to the residual contrasting enhancing mass by either interstitial brachytherapy (IB, n = 33), by interstitial thermoradiotherapy (IT, n = 25) or by stereotactic radiosurgery (SRS, n = 19). The primary aim of this study was to evaluate the role of different boosting techniques in the initial management of primary brain tumors. External beam radiotherapy doses were escalated from one study to the next so that the median doses given to the IB, the IT, and the SRS groups were 41.4 Gy, 48.4 Gy, and 59.4 Gy, respectively. The median dose of interstitial irradiation or stereotactic radiosurgery, were 40 Gy, 32.2 Gy and 10 Gy, respectively, for the same groups. Follow-up was such that all living patients had been followed for a minimum of 30, 27, 4 months in the IB, IT, and SRS groups, respectively; hence, twelve-month survival was 52% (95% CI: 34%-69%), 80% (95% CI: 64%-96%), and 51% (95% CI: 24%-78%) in the same respective groups. Using a multivariate Cox proportional hazards model, treatment with IT conferred a survival advantage over IB (p = 0.029). Furthermore, survival of patients treated with SRS did not significantly differ from that of patients treated with an implant with or without hyperthermia.(ABSTRACT TRUNCATED AT 250 WORDS)

Radiation therapy salvage of Hodgkin's disease following chemotherapy failure.

PURPOSE: This study evaluates the efficacy of comprehensive salvage radiation therapy, with or without chemotherapy, in selected patients with Hodgkin's disease who have failed primary combination chemotherapy. METHODS AND MATERIALS: Between 1972 and 1991, 28 patients with advanced Hodgkin's disease failing intensive combination chemotherapy in previously unirradiated nodal and/or pulmonary sites were treated with salvage radiotherapy with curative intent. Treatment consisted of comprehensive extended field radiotherapy to all known areas of disease. Total radiation doses ranged from 17.0 to 50.0 Gy, with only five patients (18%) receiving < 30.0 Gy to any field. Twelve patients also received chemotherapy as part of their salvage regimen. RESULTS: Twenty-six patients (93%) achieved a complete response and 14 (50%) remain in continuous complete remission at 14 to 133 months. In addition, three patients (11%) who failed salvage radiotherapy are now without evidence of disease following additional therapy. With a median follow-up of 47 months (range 14+ to 198+), actuarial median relapse-free survival and overall survival are 46 and 97 months, respectively. Actuarial 5-year relapse-free survival and overall survival are 40% and 63%, respectively. Patients with an initial complete response to chemotherapy had a significantly longer actuarial relapse-free survival than those with an initial partial response (p = 0.02). Salvage therapy was generally well-tolerated and resulted in no treatment-related deaths. CONCLUSION: Comprehensive salvage radiotherapy is of significant benefit in selected patients and should be considered an option for patients with advanced Hodgkin's disease following chemotherapy failure.

Feasibility and toxicity of transrectal ultrasound hyperthermia in the treatment of locally advanced adenocarcinoma of the prostate.

PURPOSE: This Phase I trial tests the ability of a new hyperthermia device, the transrectal ultrasound probe, to heat the prostate gland, and evaluates the toxicity of transrectal ultrasound hyperthermia (TRUSH) given with concurrent standard external beam irradiation in the treatment of locally-advanced adenocarcinoma of the prostate. METHODS AND MATERIALS: Between June, 1990 and August, 1991, 14 patients with American Urological Society Stage C2 or D1 adenocarcinoma of the prostate were treated with TRUSH concurrently with standard external beam radiotherapy to the prostate. Twenty-two heat treatments were delivered in 14 patients; 8 patients received two TRUSH procedures, each separated by 1 week. Patient age ranged between 53-86 (mean: 72) years. Three patients had well-, 6 patients had moderately-, and 5 patients had poorly-differentiated adenocarcinoma of the prostate. Karnofsky status ranged from 70-90. Standard radiotherapy to the prostate and periprostatic tissues was delivered using a four-field approach with 1.8-2 Gy daily fractions delivered 5 x/week to a total dose of 67-70 Gy calculated to the minimum tumor volume. TRUSH was delivered after transperineal placement of multipoint thermometry probes by a urologist, under transrectal ultrasound guidance. Two to three thermocouple probes containing seven sensors each were placed in the prostate in an attempt to sample temperatures throughout the gland. The sensor depth from the rectal wall ranged from 5-25 mm. RESULTS: Thirty-six percent of all sensors were heated above 42.5 degrees C averaged over 30 min; and all patients had at least some sensors within the prostate heated to temperatures > or = 42.5 degrees C. The average temperature of all sensors of all sensors (T(ave) +/- s.d.) over all treatments, however, was only 41.9 degrees C +/- 0.9 degrees C over 30 min. The maximum temperature for normal tissues outside the gland was 41.1 degrees C +/- 1.3 degrees C. Treatments have been well-tolerated with few complications. Tolerance has been "good" in 17/22, "fair" in 3/22, and "treatment limiting" in 2/22 treatments secondary to position intolerance and/or pain. There has been one episode of hypotension related to narcotic administration and three episodes of rapidly resolving pain during hyperthermia treatment. Mild hematuria has occurred in 5/22, and moderate hematuria has occurred in 2/22 transperineal thermometer catheter placements. CONCLUSION: In conclusion, TRUSH is well-tolerated and has great potential for consistently heating the prostate gland. We anticipate that further equipment modifications will improve our ability to heat the entire prostate to temperatures > 42.5 degrees C.

Template-guided stereotactic implantation of malignant brain tumors for interstitial thermoradiotherapy.

A phase I trial of 25 patients with anaplastic astrocytoma or glioblastoma multiforme is described. Hyperthermia and radiation were delivered stereotactically by means of template-guided interstitial catheters loaded with ferromagnetic wires and then 192Ir seeds. Implant volumes ranged from 15 to 113 ml (mean 54 ml) involving 9-38 catheters (mean 18); parallel catheters used hexagonal spacing of 1.0-1.5 cm. Patient tolerance of these procedures was excellent. Postoperative morbidity due to additional mass effect or edema was low, but there has been one death and one complication of hydrocephalus, bleeding and symptomatic pneumocephalus, each.

Treatment of malignant gliomas with interstitial irradiation and hyperthermia.

A Phase I study of interstitial thermoradiotherapy for high-grade supratentorial gliomas has been completed. The objective of this trial was to test the feasibility and toxicity of hyperthermia induced by ferromagnetic implants in the treatment of intracranial tumors. The patient population consisted of 16 males and 12 females, with a median age of 44 years and a median Karnofsky score of 90. Nine patients had anaplastic astrocytoma while 19 had glioblastoma multiforme. Twenty two patients were treated at the time of their initial diagnosis with a course of external beam radiotherapy (median dose 48.4 Gy) followed by an interstitial implant with Ir-192 (median dose 32.7 Gy). Six patients with recurrent tumors received only an interstitial implant (median dose 40 Gy). Median implant volume for all patients was 55.8 cc and median number of treatment catheters implanted per tumor was eighteen. A 60-minute hyperthermia treatment was given through these catheters just before and right after completion of brachytherapy. Time-averaged temperatures of all treatments were computed for sensors located within the core of (> 5 mm from edge of implant), and at the periphery of the implant (outer 5 mm). The percentage of sensors achieving an average temperature > 42 degrees C was 61% and 35%, respectively. Hyperthermia was generally well tolerated; however, there have been 11 minor toxicities, which resolved with conservative management, and one episode of massive edema resulting in the death of a patient. In addition, there were three major complications associated with the surgical implantation of the catheters. Preliminary survival analysis shows that 16 of the 28 patients have died, with a median survival of 20.6 months from diagnosis. We conclude that interstitial hyperthermia of brain tumors with ferromagnetic implants is feasible and carries significant but acceptable morbidity given the extremely poor prognosis of this patient population.

Pterygium treated with excision and postoperative beta irradiation.

A retrospective study was done of 338 patients with pterygia treated between October 1974 and May 1990. These patients resided in the desert of the southwestern United States, where the hot, dry, dusty climate is thought to predispose to pterygium formation and subsequent recurrence. The pterygia were excised, and the administration of beta irradiation was initiated within 24 hr of surgery. Sixteen percent of the pterygia were recurrent. Ninety-five percent of the beta irradiation prescriptions consisted of 3 weekly 800 cGy fractions. For patients with a minimum of 6 months follow-up, the crude local control rate was 225/258 (88%). The Kaplan-Meier estimate of the 5-year local control rate was 84% (95% confidence interval: 79-89%). Ten of 33 recurrences were diagnosed within 6 months, and 32/33 recurrences were diagnosed within 5 years of treatment. Previously untreated pterygia were controlled more easily than were recurrent pterygia (p = 0.005). In 86% of the cases, patients judged the cosmetic results to be satisfactory. No severe complications developed. This study and others, when compared with studies involving excision alone, suggest that postoperative beta irradiation reduces the likelihood for pterygium recurrence. When the beta irradiation is fractionated, satisfactory cosmetic results can be achieved with low morbidity.

Recurrent basal cell carcinoma treated with radiation therapy.

A retrospective study was performed of 61 recurrent basal cell carcinomas treated with radiation therapy between 1974 and 1990 at the University of Arizona College of Medicine or at Southwestern Radiation Oncology, Tucson, Arizona. The median length of follow-up was 57 months. Applying the American Joint Committee on Cancer staging system to these recurrent tumors, 36 were stage I, 19 were stage II, five were stage III, and one was stage IV. Kaplan-Meier methods were used to estimate the 5-year complete remission rates. The Mantel-Haenszel Test and the Cox Proportional Hazards Model were used to determine if tumor size, stage, histologic subtype, anatomic site, age, sex, dose, number of radiation therapy treatments, length of time over which the radiation therapy was administered, or type of radiation beam used (orthovoltage x-rays vs megavoltage electrons) affected the 5-year complete remission rates. Only tumor size and stage had a statistically significant effect on the complete remission rates. The Kaplan-Meier estimates of the 5-year complete remission rates for 0.5- to 1.0-cm tumors vs tumors larger than 1.0 cm were 96% (95% confidence interval, 88% to 100%) and 81% (95% confidence interval, 64% to 99%), respectively. The Kaplan-Meier estimates of the 5-year complete remission rates for stage I/II tumors vs stage III/IV tumors were 93% (95% confidence interval, 85% to 100%) and 42% (95% confidence interval, 8% to 84%), respectively. Functional and cosmetic results were frequently good to excellent at 5 years. Soft-tissue necrosis developed in two of 61 cases, and was successfully managed in both. This article, combined with a review of the literature, suggests that radiation therapy is an effective method of treating recurrent basal cell carcinomas.