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Featured researches published by Joseph R. Castro.


Cancer | 1973

Rhabdomyosarcoma of head and neck in children

Sarah S. Donaldson; Joseph R. Castro; Jordan R. Wilbur; Richard H. Jesse

Combined systematic therapy offers the best chance of cure for children with rhabdomyosarcoma originating in the head and neck. Recommended therapy includes: 1. local excision or biopsy; 2. radiation therapy with doses of 6,000 rads/6 weeks, and 3. multi‐drug chemotherapy, i.e., vincristine sulfate, actinomycin D, and cyclophosphamide. Severe ocular, dental, soft tissue, and possibly bone complications may be encountered. Provision for prompt medical and nursing support must be available for possible associated morbidity. Of 19 patients treated, minimum 2‐year survival is 74%, and local control 89%. Late recurrences or complications require further follow‐up.


International Journal of Radiation Oncology Biology Physics | 1988

Charged particle irradiation of chordoma and chondrosarcoma of the base of skull and cervical spine: the Lawrence Berkeley Laboratory experience.

Anthony M. Berson; Joseph R. Castro; Paula L. Petti; Theodore L. Phillips; Grant E. Gauger; Philip H. Gutin; J.Michael Collier; Sheri D. Henderson; Kari Baken

Forty-five consecutive patients with chordoma or chondrosarcoma at the base of skull or cervical spine were treated at the University of California Lawrence Berkeley Laboratory (UCLBL) and University of California School of Medicine, San Francisco (UCSF) between November 1977 and October 1986. All patients had undergone a subtotal surgical resection. Twenty-three patients were treated definitively with charged particles, 13 patients were treated with photons and particles, and 9 patients were treated for recurrent disease. Total doses ranged from 36 to 80 Gray equivalent (GyE). Thirty-three patients are alive with a minimum followup of 1 year. The actuarial survival and local control for all patients at 5 years is 62% and 59%, respectively. Patients treated for primary disease had a 78% actuarial local control rate at 2 years, whereas the rate for patients with recurrent disease was 33%. Patients with smaller visible tumor volumes (less than 20 cc) had a significantly better local control rate than patients with larger tumor volumes (80% vs 33% actuarial rate at 5 years). Patients with chondrosarcoma had the highest local control rate, as did patients treated with particles alone. Complications included 3 patients with unilateral visual loss, two patients who became blind, and 4 patients with radiation injury to the brainstem.


International Journal of Radiation Oncology Biology Physics | 1996

15 years experience with helium ion radiotherapy for uveal melanoma

Joseph R. Castro; Devron H. Char; Paula Petti; Inder K. Daftari; Jeanne M. Quivey; Rajindar P. Singh; Eleanor A. Blakely; Theodore L. Phillips

PURPOSE To review the long-term experience of helium ion therapy as a therapeutic alternative to enucleation for uveal melanoma, particularly with respect to survival, local control, and morbidity. METHODS AND MATERIALS 347 patients with uveal melanoma were treated with helium ion RT from 1978-1992. A nonrandomized dose-searching study was undertaken, with doses progressively reduced from 80 GyE in five fractions to 48 GyE in four fractions, given in 3-15 days, mean of 7 days. RESULTS Local control was achieved in 96% of patients, with no difference in the rate of local control being seen at 80, 70, 60, or 50 GyE in five fractions. At the lowest dose level of 48 GyE in four fractions, the local control rate fell to 87%. Fifteen of 347 patients (4%) had local regrowth in the eye requiring enucleation (12 patients), laser (1 patient) or reirradiation (2 patients). The time of appearance of local regrowth ranged from 4 months to 5 years posttreatment, with 85% occurring within 3 years. Of the 347 patients, 208 are alive as of May 1, 1997. The median follow up of all patients is 8.5 years, range 1-17 years. Kaplan-Maier (K-M) survival is 80% at 5 years, 76% at 10 years, and 72% at 15 years posttreatment. Patients with tumors not involving the ciliary body have a 15-year K-M survival of 80%. The results for patients whose tumors involved the ciliary body are poor, with a 15-year K-M survival of 43%. Seventy-five percent of patients with tumors at least 3.0 mm from the fovea and optic nerve, and initial ultrasound height less than 6.0 mm, retained vision of 20/200 or better posttreatment. Patients with tumors larger than 6 mm in thickness, or with tumors lying close to the optic nerve or fovea, have a reduced chance of retaining useful vision. The enucleation rate is 19%, 3% for local failure and 16% because of complications of the helium RT, particularly neovascular glaucoma, which occurred in 35% of patients. CONCLUSIONS Local control and retention of the eye are excellent. Complications of therapy reduce vision and eye preservation. Twenty-four percent of patients manifested distant metastases 6 to 146 months posttreatment, mean of 43 months, median of 36 months. Late-appearing distant metastases do not appear to be caused by persistent tumor in the eye. The risk of metastases is high for patients with tumors greater than 7 mm in initial ultrasound height (37%), anterior tumors involving the ciliary body (47%), and in those with local failure (53%). Patients with tumors not involving the ciliary body and initial dimensions less than 10 mm had only an 8% chance of death from melanoma. A search for effective adjuvant therapy is needed for patients at high risk of metastases (large tumors, ciliary body involved, local regrowth in eye).


Annals of Surgery | 1994

Carcinoma of the extrahepatic bile ducts : the University of California at San Francisco experience

Robin Schoenthaler; Theodore L. Phillips; Joseph R. Castro; Jimmy T. Efird; Abert Better; Lawrence W. Way

ObjectiveThe authors investigated the combined experience of a single institution in treating bile duct carcinoma during the modern era. Summary Background DataBile duct carcinomas are notoriously difficult to cure, with locoregional recurrence the rule, even after radical resection. Adjuvant efforts have included various radiation modalities, with limited success. Recently, charged-particle radiotherapy has also been used in these patients. MethodsThe authors performed a retrospective chart analysis of 129 patients with bile duct adenocarcinomas treated between 1977 and 1987 through the University of California at San Francisco, including 22 patients treated at Lawrence Berkeley Laboratory with the charged particles helium and neon. The minimum follow-up was 5 years. Survival, outcome, and complication results were analyzed. ResultsSixty-two patients were treated with surgery alone (S), 45 patients received conventional adjuvant x-ray radiotherapy (S + X), and 22 were treated with charged particles (S + CP). The median survival times were 6.5, 11, and 14 months, respectively, for the entire group, and 16, 16, and 23 months in patients treated with curative intent.There was a survival Difference in patients undergoing total resection compared with debulking (p = 0.05) and minor resections (p = 0.0001), Patients with microscopic residual disease had increased median survival times when they were treated with adjuvant irradiation, most markedly after CP (p = 0.0005) but also with conventional X (p = 0.0109). Patients with gross residual disease had a less marked but still statistically significant extended survival (p = 0.05 for S + X and p = 0.0423 for S + CP) after irradiation. ConclusionsThe mainstay of bile duct carcinoma management was maximal surgical resection in these patients. Postoperative radiotherapy gave patients with positive microscopic margins a significant survival advantage and may be of value in selected patients with gross disease.


Archives of Ophthalmology | 1990

Five-Year Follow-up of Helium Ion Therapy for Uveal Melanoma

Devron H. Char; Joseph R. Castro; Stewart Kroll; Alexander R. Irvine; Jeanne M. Quivey; R. Dudley Stone

One hundred sixty-four patients with uveal melanoma were treated with helium ion irradiation prior to May 1984, and the data were analyzed in June 1989. Most uveal melanomas were large, with a mean tumor thickness of 6.5 mm; approximately 60% of the patients had tumors that extended anterior to the equator. A complete follow-up was obtained for all patients. One hundred twelve patients were alive at the time of this report; 18% of the patients developed clinical and laboratory evidence of metastases and eventually died of widespread tumor. Eighty-four percent of eyes were retained. Data were analyzed with a number of parametric and nonparametric techniques. Larger tumors and those located in close proximity to the optic nerve and fovea had a higher incidence of most complications, especially visual loss.


International Journal of Radiation Oncology Biology Physics | 1993

Charged particle irradiation of sacral chordomas

Robin Schoenthaler; Joseph R. Castro; Paula Petti; Kari Baken-Brown; Theodore L Hillips

PURPOSE The purpose of this report is determine the impact of charged particle irradiation at Lawrence Berkeley Laboratory (LBL) in treating patients with sacral chordomas. Overall survival, local control, complications, and predictive parameters are analyzed. METHODS AND MATERIALS Fourteen patients with sacral chordomas were treated with the charged particles helium and neon between 1977 and 1989. The median dose was 7565 cGyE and the median follow up is 5 years. All patients were treated post-operatively; ten had gross residual disease. RESULTS Kaplan-Meier survival at 5 years is 85%. Overall 5-year local control is 55%. A trend to improved local control at 5 years was seen in patients treated with neon when compared to patients treated with helium (62% vs 34%), in patients following complete resection versus patients with gross residual tumor (75% vs 40%), and in patients who had treatment courses under 73 days (61% vs 21%). Distant metastases were seen in two patients (14%). No patient developed neurologic sequelae or pain syndromes. One previously irradiated patient required colostomy, one patient had delayed wound healing following a negative post-radiation biopsy, and one patient developed a second malignancy. There were no genitourinary complications. CONCLUSION Our experience indicates that post-operative charged particle irradiation of sacral chordomas appears to result in reasonable local control and survival with acceptable risk, and that additional evaluation on the use of heavy charged particles is warranted.


International Journal of Radiation Oncology Biology Physics | 1991

High intensity 125-Iodine (1251) plaque treatment of uveal melanoma☆

Jeanne M. Quivey; Devron H. Char; Theodore L. Phillips; Keith A. Weaver; Joseph R. Castro; Stewart Kroll

PURPOSE Episcleral 125I plaque therapy of uveal melanoma is an important treatment modality to control tumor, salvage the globe, and potentially preserve vision. We retrospectively analyzed our experience in 239 patients to assess treatment outcome with this technique. METHODS AND MATERIALS Between 1983 and 1990, 239 uveal melanoma patients were treated with 125I plaques at the University of California, San Francisco. High intensity 125I seeds in the range of 3-20 mCi were used to give a minimum tumor dose of 70 Gy in 4 days. Initial mean tumor size was 10.9 mm x 9.2 mm x 5.5 mm with a range in tumor diameter from 4 to 18 mm and tumor height from 1.9 to 11.1 mm. Best corrected pre-treatment visual acuity was 20/200 or better in 92% of patients. RESULTS Local tumor control was maintained in 91.7% of patients with a mean follow-up of 35.9 months; 19 patients had local tumor progression; mean time to progression was 27.3 mo (1.8 to 60.1 mo). Actuarial local control is 82% at 5 years. Multivariate analysis demonstrates significant correlation of local failure with larger maximum tumor diameter (p = 0.0008), closer proximity to the fovea (p = 0.0001), lower radiation dose (p = 0.0437), and smaller ultrasound height (p = 0.0034). The actuarial incidence of distant metastases is 12% at 5 years with multivariate analysis showing significant correlation only with maximum tumor diameter (p = 0.0064). Visual outcome is 20/200 or better in 58% of patients. CONCLUSION While the tumor control rates appear favorable, ocular morbidity is significant. A current randomized trial comparing 125I plaque with Helium ion therapy is in progress with specific comparison of tumor control, survival, and visual outcome.


Ophthalmology | 1997

Metastatic Risk for Distinct Patterns of Postirradiation Local Recurrence of Posterior Uveal Melanoma

J. William Harbour; Devron H. Char; Stew Kroll; Jeanne M. Quivey; Joseph R. Castro

OBJECTIVE The purpose of the study is to compare the prognostic significance of horizontal/marginal versus vertical/diffuse patterns of postirradiation local recurrence of posterior uveal melanoma. DESIGN The study design was a nonrandomized, retrospective clinical study. Semiparametric and nonparametric statistical techniques were used. PARTICIPANTS Seven hundred sixty-six posterior uveal melanoma patients were studied. INTERVENTION Either iodine-125 plaque or helium ion radiation therapy was performed. MAIN OUTCOME MEASURES Local tumor recurrence and systemic metastasis were measured. RESULTS Local tumor recurrence was detected in 66 (8.6%) of 766 irradiated tumors. The 5-year actuarial rate of local recurrence was 10%. The recurrence pattem was horizontal/marginal in 27 patients (41%) and vertical/diffuse in 39 patients (59%). Systemic metastasis was detected in 5 patients (19%) with horizontal/marginal recurrence and in 19 patients (49%) with vertical/diffuse recurrence. After known metastatic risk factors were controlled, the relative risk for metastasis was 2.2 for horizontal/marginal recurrence and 5.1 for vertical/diffuse recurrence (P = 0.05). The actuarial rate of systemic metastasis was 2.9% per year for all patients, 6.3% per year for patients with horizontal/marginal recurrence, and 15.5% per year for patients with vertical/diffuse recurrence. CONCLUSIONS Postirradiation local recurrence of posterior uveal melanoma is a risk factor for systemic metastasis. Vertical/diffuse recurrences may be associated more strongly with metastatic disease than horizontal/marginal recurrences.


International Journal of Radiation Oncology Biology Physics | 1991

Neon ion radiotherapy: Results of the phase I/II clinical trial

David E. Linstadt; Joseph R. Castro; Theodore L. Phillips

Neon ion radiotherapy possesses biologic and physical advantages over megavoltage X rays. Biologically, the neon beam reduces the oxygen enhancement ratio and increases relative biological effectiveness. Cells irradiated by neon ions show less variation in cell-cycle related radiosensitivity and decreased repair of radiation injury. The physical behavior of heavy charged particles allows precise delivery of high radiation doses to tumors while minimizing irradiation of normal tissues. In 1979 a Phase I-II clinical trial was started at Lawrence Berkeley Laboratory using neon ions to irradiate patients for whom conventional treatment modalities were ineffective. By the end of 1988 a total of 239 patients had received a minimum neon physical dose of 1000 cGy (median follow-up for survivors 32 months). Compared with historical results, the 5-year actuarial disease-specific survival (DSS5) and local control (LC5) rates suggest that neon treatment improves outcome for several types of tumors: a) advanced or recurrent macroscopic salivary gland carcinomas (DSS5 59%; LC5 61%); b) paranasal sinus tumors (DSS5 69%; LC5 69% for macroscopic disease); c) advanced soft tissue sarcomas (DSS5 56%, LC5 56% for macroscopic disease); d) macroscopic sarcomas of bone (DSS5 45%; LC5 59%); e) locally advanced prostate carcinomas (DSS5 90%; LC5 75%); and f) biliary tract carcinomas (DSS5 28%; LC5 44%). Treatment of malignant gliomas, pancreatic, gastric, esophageal, lung, and advanced or recurrent head and neck cancer has been less successful; results for these tumors appear no better than those achieved with conventional x-ray therapy. These findings suggest that Phase III trials using the neon beam should be implemented for selected malignancies.


International Journal of Radiation Oncology Biology Physics | 1985

Precision, high dose radiotherapy: Helium ion treatment of uveal melanoma

William M. Saunders; Devron H. Char; Jeanne M. Quivey; Joseph R. Castro; George T.Y. Chen; J.Michael Collier; Aude Cartigny; Eleanor A. Blakely; John T. Lyman; Sandra R. Zink; Cornelius A. Tobias

We report on 75 patients with uveal melanoma who were treated by placing the Bragg peak of a helium ion beam over the tumor volume. The technique localizes the high dose region very tightly around the tumor volume. This allows critical structures, such as the optic disc and the macula, to be excluded from the high dose region as long as they are 3 to 4 mm away from the edge of the tumor. Careful attention to tumor localization, treatment planning, patient immobilization and treatment verification is required. With a mean follow-up of 22 months (3 to 60 months) we have had only five patients with a local recurrence, all of whom were salvaged with another treatment. Pretreatment visual acuity has generally been preserved as long as the tumor edge is at least 4 mm away from the macula and optic disc. The only serious complication to date has been an 18% incidence of neovascular glaucoma in the patients treated at our highest dose level. Clinical results and details of the technique are presented to illustrate potential clinical precision in administering high dose radiotherapy with charged particles such as helium ions or protons.

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Paula Petti

University of California

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Stewart Kroll

University of California

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