Biomedical subjects

Robert B Marcus

Publications and source records attributed to Robert B Marcus.

10 recordsLinked to original sources

PubMed2007

Neuroblastoma in adults: Incidence and survival analysis based on SEER data.

PURPOSE: Clinical data on survival outcomes of adult patients (defined as 20 years of age and older) with neuroblastoma are scarce due to the rarity of the disease. Small single institution reports have described worse outcomes for adults than pediatric patients. MATERIALS/METHODS: Data from the public access Surveillance Epidemiology and End Results database were reviewed for a 30-year period between 1973 and 2002 for the diagnosis of neuroblastoma. Analyses compared frequency and survival rates of neuroblastoma among children and adults with particular focus on the incidence, case characteristics, and long-term survival of the adult patients. RESULTS: The observed 3- and 5-year survival rates were lowest among adult patients (45.9% and 36.3%, respectively), whereas infants fared best with 86.0% 3-year and 84.6% 5-year overall survival. There was a steady decline in the incidence of adult neuroblastoma from 0.47 cases per million per year in 1973-1977 to 0.12 cases per million per year in 1998-2002. When the long-term adult neuroblastoma survival was examined in detail for 1-, 3-, 5-, 7-, and 10-year follow-up periods, there was continuous decrease in survival during the first 7 years after the diagnosis with subsequent stabilization for both observed (OS) and relative survival (RS) rates. There was a notable trend towards improved outcome over the past three decades. CONCLUSIONS: Adults with neuroblastoma have significantly worse outcome than children. This may be due to tumor biology, more virulent clinical course, or possibly due to the fact that adults are less sensitive or have poor tolerance to pediatric chemotherapy regimens.

Adolescent↗

PubMed2006

Low-dose prophylactic craniospinal radiotherapy for intracranial germinoma.

PURPOSE: To report outcomes of patients with localized intracranial germinoma treated with low-dose craniospinal irradiation (CSI) followed by a boost to the ventricular system and primary site. METHODS AND MATERIALS: Thirty-one patients had pathologically confirmed intracranial germinoma and no spine metastases. Low-dose CSI was administered in 29 patients: usually 21 Gy of CSI, 9.0 Gy of ventricular boost, and a 19.5-Gy tumor boost, all at 1.5 Gy per fraction. Our neuroradiologist recorded three-dimensional tumor size on magnetic resonance images before, during, and after radiotherapy. RESULTS: With a median follow-up of 7.0 years, 29 of 31 patients (94%) are disease free. One failure had nongerminomatous histology; the initial diagnosis was a sampling error. Of 3 patients who did not receive CSI, 1 died. No patient developed myelopathy, visual deficits, dementia, or skeletal growth problems. In locally controlled patients, tumor response according to magnetic resonance scan was nearly complete within 6 months after radiotherapy. CONCLUSIONS: Radiotherapy alone with low-dose prophylactic CSI cures almost all patients with localized intracranial germinoma. Complications are rare when the daily dose of radiotherapy is limited to 1.5 Gy and the total CSI dose to 21 Gy. Patients without a near-complete response to radiotherapy should undergo resection to rule out a nongerminomatous element.

Adolescent↗

PubMed2006

Comparison of conventional to intensity modulated radiation therapy for abdominal neuroblastoma.

OBJECTIVE: To compare three different techniques of irradiating abdominal neuroblastoma. PATIENTS AND METHODS: Six children with a median age of 4.1 years underwent radiotherapy (RT) to the primary site as part of treatment for high-risk neuroblastoma. Four had midline disease while two had well-lateralized lesions. Three different RT techniques were compared. Technique A used parallel-opposed AP/PA fields prescribed to the midplane of the patient. For Techniques B and C, intensity modulated radiation therapy (IMRT) plans were developed using inverse treatment planning with a sliding window or dynamic multileaf collimator approach, seven coplanar beams, and a 0.25 x 0.5 cm minimum beam resolution. The clinical target volume (CTV) included the tumor present prior to second look surgery but after induction chemotherapy with a 1.5 cm margin. The planning target volume (PTV) was the CTV with a 0.5 cm margin. The CTV was planned to receive 100% of the prescribed dose. For Technique C, the vertebral bodies adjacent to the tumor were included in the PTV to minimize heterogeneity of dose. Six MV photons were used for all techniques. Bilateral kidneys, liver, spine, spleen, stomach and bilateral iliac crests were contoured. RESULTS: Dose to the PTV and CTV were not significantly different using the three techniques. In comparison to Technique A, Techniques B and C delivered a lower mean dose to the bilateral kidneys in the four children with midline tumors but not the two children with a lateralized tumor where the contralateral kidney received a higher mean dose. Dose to the spine was less homogeneous with Technique B compared to Techniques A and C. The spleen, liver and stomach mean doses were higher using Techniques B and C compared to Technique A. CONCLUSION: Although Technique C was the best method of RT delivery in midline tumors with respect to kidney doses, this was at a cost of a higher mean dose to the liver, stomach, and spleen. This, together with the theoretical increase in secondary malignancies, should be considered when treating a child with IMRT techniques. IMRT was not found to be better than the conventional AP/PA field for lateralized tumors.

Abdominal Neoplasms↗

PubMed2004

Extra-target doses in children receiving multileaf collimator (MLC) based intensity modulated radiation therapy (IMRT).

PURPOSE: To investigate the extra-target doses using intensity modulated radiation therapy (IMRT). MATERIALS AND METHODS: Thirteen children underwent multileaf collimator (MLC)-based IMRT. Treatment site was head and neck or brain in eight (Group I), trunk in two (Group II), and abdomen/pelvis in three (Group III). Thermoluminescent dosimeters (TLD) were placed at the thyroid gland, breast, and testis. A control group of seven children received conventional RT and TLD measurements. RESULTS: For the eight Group I children, the median dose equivalent measurements during the course of IMRT to the thyroid, breast, and testis were 348 mSv, 110 mSv, and 30 mSv, respectively. For the two Group II patients, the measurements to the thyroid ranged from 1,525 to 2,449 mSv while for the testis was 62 mSv. For the Group III patients, the median dose equivalent measurements to the thyroid, breast, and testis were 182 mSv, 406 mSv, and 159 mSv. The median dose equivalent measurements to the thyroid, breast, and testis for Group I children were 300 mSv, 120 mSv, and 75 mSv. The Group II conventional patient had a measurement of 180 mSv, 80 mSv, and 80 mSv to the thyroid, breast, and testis. For the Group III conventional cases, the median dose equivalent measurements were 192 mSv, 496 mSv, and 434 mSv. CONCLUSIONS: No significant difference was seen in the thyroid and breast doses of children receiving MLC-based IMRT compared to conventional RT for the treatment of head and neck/brain and abdominal/pelvic tumors.

Abdominal Neoplasms↗

PubMed2004

The effect of an extended source-to-skin distance in the treatment of the spinal field in children receiving craniospinal irradiation.

In this study, we compared a single extended source-to-skin difference (SSD) spinal field and the alternative 2-field gapped approach at 100 SSD on dose to surrounding normal tissues. Five female patients ranging in age from 3 to 20 years underwent computed tomography (CT) simulation for treatment planning of the craniospinal axis, which was treated in its entirety to 36 Gy. For each slice, the clinical target volume (thecal sac and contents), mandible, thyroid gland, esophagus, heart, lungs, liver, and ovaries were contoured. Technique A employed the use of a single posterior spinal field delivered at SSD = 140 cm (140 SSD), and Technique B employed the use of 2 gapped spinal fields using a traditional SSD of 100 cm (100 SSD). Dose-volume histograms (DVHs) were obtained for each organ contoured and for each technique used. In all patients, the average mean dose to all surrounding structures was increased with the use of a single extended SSD (Technique A) when compared to the 2 spinal fields prescribed at 100 SSD (Technique B). The average mean doses to the mandible, thyroid gland, esophagus, and heart were 78%, 19%, 6%, and 16%, respectively, higher with Technique A as compared to Technique B. In addition, the average mean doses to the lungs, liver, and ovaries were 53%, 33% and 69%, respectively, higher as compared to Technique B. However, the clinical target volume at the spinal junction site received a less homogenous dose with Technique B as compared to Technique A. We conclude that although the use of a single-field extended SSD delivered a more homogenous dose to the spine, a higher dose to the ovaries, thyroid gland, mandible, lungs, liver, and heart was seen.

Adult↗

PubMed2003

Radiation therapy for angiosarcoma.

BACKGROUND: Between 1964 and 1998, 19 patients with histologically proven angiosarcoma were treated with curative intent with radiation therapy. METHODS: Median follow-up was 37 months (range, 8-234 months). RESULTS: The actuarial 5-year absolute survival and local control rates were 51% and 50%, respectively. Of 12 patients who relapsed, 8 had isolated local recurrence as the first site of treatment failure, 2 had local (1 patient) or regional recurrence in conjunction with distant metastases, and 2 had distant metastases alone. Two of four patients who underwent further therapy for recurrent disease were successfully salvaged. CONCLUSIONS: Only the location of the primary tumor was a predictor of local control and absolute survival at 5 years. Angiosarcomas located on the scalp imply a dismal prognosis compared with those in other locations with the predominant pattern of failure being local recurrence. Patients should be treated aggressively with surgical resection and preoperative or postoperative radiation therapy.

Adult↗

PubMed2003

Oligodendroglioma: does deferring treatment compromise outcome?

This study reports the University of Florida experience treating oligodendrogliomas with the goal of identifying the factors that predict favorable outcome. Between 1958 and June 1998, 51 patients (aged 5-75 years) were diagnosed with pure oligodendroglioma at the University of Florida. Histologic grade was anaplastic in 19 patients, low-grade in 30 patients, and unknown in one patient. Twelve patients were treated with surgery alone (10 with low-grade tumors). Thirty-nine patients underwent postoperative radiotherapy after surgery (plus chemotherapy in four patients). A biopsy was performed in 10 patients, 40 underwent subtotal or gross total resection, and one had surgery of unknown extent. Thirteen patients with a radiographic abnormality consistent with a low-grade glioma had the initiation of definitive treatment (i.e., surgery with or without radiotherapy) deferred for a median of 4.5 years before undergoing treatment for worsening symptoms or radiographic progression. Absolute survival for the entire group (51 patients) at 5, 10, and 20 years from the date of initial treatment was 61%, 37%, and 31%, respectively, and at 5, 10, and 20 years from the date of initial diagnosis was 65%, 43%, and 34%, respectively. No patient died of intercurrent disease. Multivariate analysis for absolute survival from the time of initial treatment demonstrated young age (young patients fared better than older patients) and size (<5 cm better than > or =5 cm) to be significant variables. No patient under the age of 21 years (n = 8) at the time of diagnosis has died in this series. Deferring aggressive treatment did not alter survival. Multivariate analysis for favorable absolute survival based on the time from initial diagnosis demonstrated young age and presentation with seizures alone to be statistically significant for favorable outcomes. Approximately one third of patients with oligodendroglioma appear to be cured with aggressive treatment. Age is the most important predictor of long-term progression-free and absolute survival with young patients (especially aged <21 years) doing much better than older patients. Deferring aggressive treatment (surgery and/or radiation) until symptoms clearly indicate tumor progression does not compromise outcome for a select group of patients who are diagnosed at a young age with a nonenhancing mass on MR and seizures as the lone presenting symptom.

Adolescent↗

PubMed2003

Role of radiotherapy in the treatment of neurosarcoidosis.

Neurosarcoidosis is usually managed with steroids, immunosuppressives, and other medications. Several small series suggest that radiotherapy might be useful in patients whose disease is refractory to conventional treatment. The purpose of this article is to report the outcome of 4 patients with neurosarcoidosis who were treated at the University of Florida. With long-term follow up, partial regression of disease was observed in 2 patients, stabilization of disease in 1 patient, and disease progression in 1 patient. Our experience and review of the related literature suggest the following conclusions: (1) radiotherapy is often effective in preventing the progression of local symptoms from neurosarcoidosis, but has limited application in reversing established neurologic deficits; (2) sarcoid meningitis is responsive to radiotherapy; and (3) radiation dose for the palliation of symptoms related to neurosarcoidosis is 20 to 25 Gy.

Adult↗

PubMed2002

External beam radiotherapy for primary and adjuvant management of aggressive fibromatosis.

PURPOSE: To review a large single-institution experience in the management of aggressive fibromatosis to determine the effectiveness of external beam radiotherapy (EBRT) and identify the presentation and treatment variables predictive of locoregional control. METHODS AND MATERIALS: Between 1975 and 2000, 72 patients were treated with EBRT for a pathologically confirmed diagnosis of aggressive fibromatosis. Thirty patients were treated at the primary presentation and 42 at the time of a locoregional recurrence. Minimal 2-year follow-up data were available for 65 patients (median 6 years). Megavoltage irradiation with 60Co to 20 MV photons or electron therapy was used for all patients. Most patients were treated after attempted complete surgical resection; 16 patients underwent pretreatment biopsy alone. The prescribed treatment was standard (1.8 Gy) daily fractions in 42 cases and 1.2 Gy fractions b.i.d. in 23 cases. The median prescribed dose was 54 Gy. The prognostic variables and treatment results were evaluated by Kaplan-Meier actuarial analysis. RESULTS: Locoregional control was achieved in 52 of 65 patients. The 5-year actuarial locoregional control was 83%. Locoregional failure occurred in 13 patients (11 in patients with recurrent tumors). Only two failures occurred within the irradiation fields; nine failures occurred at the field margins. Eleven patients were salvaged by surgery: wide excision in nine and amputation in two. The only prognostic factor significant for locoregional control was primary vs. recurrent presentation (p = 0.0193). The 5-year locoregional control rates for irradiation at initial presentation and at recurrence were 96% and 75%, respectively. The variables without significance for locoregional control included primary tumor location, surgical procedures performed, resection margins, and gross vs. microscopic residual tumor at irradiation. Lymphedema was the most common late effect, occurring in 7 patients, 5 with prior treatment. Bone fracture occurred in 3 patients; all 3 had fibromatosis involving the bone at presentation but without recurrence at the time of fracture. CONCLUSION: EBRT is effective treatment for aggressive fibromatosis. The probability of locoregional control decreases with multiple prior recurrences.

Adolescent↗

PubMed2002

Whole-lung radiotherapy for giant cell tumors of bone with pulmonary metastases.

Three patients initially diagnosed with benign giant cell tumors of bone who had lung metastases develop were treated with whole-lung radiotherapy as part of the therapeutic treatment of their distant disease. External beam therapy to 16 Gy in 10 fractions was delivered to the whole lung, with a boost of 35 to 45 Gy to sites of gross metastatic disease. One patient's lung metastases progressed after treatment, and the patient soon died. The two other patients were long-term survivors (7.5 years and 13 years) with complete resolution of detectable disease. One of the two patients required two additional courses of local radiation to metastatic sites. The authors therefore recommend whole lung radiotherapy to 16 Gy with an additional boost to 35 to 45 Gy to gross disease as an option for patients with pulmonary metastases who are poor surgical candidates, who refuse thoracic surgery, whose disease is technically unresectable, or whose disease recurs or progresses after surgery or chemotherapy.

Adult↗