FLASH radiotherapy for the treatment of symptomatic bone metastases in the thorax (FAST-02): protocol for a prospective study of a novel radiotherapy approach

BACKGROUND

FLASH therapy is a treatment technique in which radiation is delivered at ultra-high dose rates (≥ 40 Gy/s). The first-in-human FAST-01 clinical trial demonstrated the clinical feasibility of proton FLASH in the treatment of extremity bone metastases. The objectives of this investigation are to assess the toxicities of treatment and pain relief in study participants with painful thoracic bone metastases treated with FLASH radiotherapy, as well as workflow metrics in a clinical setting.

METHODS

This single-arm clinical trial is being conducted under an FDA investigational device exemption (IDE) approved for 10 patients with 1-3 painful bone metastases in the thorax, excluding bone metastases in the spine. Treatment will be 8 Gy in a single fraction administered at ≥ 40 Gy/s on a FLASH-enabled proton therapy system delivering a single transmission proton beam. Primary study endpoints are efficacy (pain relief) and safety. Patient questionnaires evaluating pain flare at the treatment site will be completed for 10 consecutive days post-RT. Pain response and adverse events (AEs) will be evaluated on the day of treatment and on day 7, day 15, months 1, 2, 3, 6, 9, and 12, and every 6 months thereafter. The outcomes for clinical workflow feasibility are the occurrence of any device issues as well as time on the treatment table.

DISCUSSION

This prospective clinical trial will provide clinical data for evaluating the efficacy and safety of proton FLASH for palliation of bony metastases in the thorax. Positive findings will support the further exploration of FLASH radiation for other clinical indications including patient populations treated with curative intent.

REGISTRATION

ClinicalTrials.gov NCT05524064.

Safety and Efficacy of Stereotactic Radiosurgery with Concurrent Targeted Systemic Therapy for Brain Metastases

PURPOSE/OBJECTIVE(S)

Data describing the safety and efficacy of central nervous system (CNS)-active targeted systemic therapies in combination with stereotactic radiosurgery (SRS, 1 fraction) and/or radiotherapy (SRT, 3-5 fractions) for brain metastases are emerging but limited. We report rates of local and intracranial failure and radiation necrosis in patients receiving CNS-active targeted systemic therapy and SRS/SRT.

MATERIALS/METHODS

We retrospectively identified patients with intact brain metastases at two institutions from 2009-2022 who were treated with SRS/SRT and CNS-active targeted systemic therapy in any sequence. Patients were followed for a minimum of 3 months after SRS/SRT with brain MRI. Patients typically stopped the targeted agent 2-4 days prior to radiation and resumed 2-4 days after. Targeted therapies included inhibitors of ALK/ROS1 (Alectinib, Ceritinib, Crizotinib, Lorlatinib), EGFR (Afatinib, Erlotinib, Gefitinib, Osimertinib), BRAF (Dabrafenib, Encorafenib, Vemurafenib), MEK (Binimetinib, Trametinib), CDK 4/6 (Abemaciclib, Palbociclib, Ribociclib), HER2 (Afatinib, Lapatinib, Neratinib, Pertuzumab, Trastuzumab, T-DM1, T-DXd, Tucatinib), KRAS (Adagrasib and Sotorasib), PARP (Niraparib, Olaparib), VEGF(R) (Axitinib, Bevacizumab, Ramucirumab), and less-selective tyrosine (receptor) kinase inhibitors (Bosutinib, Brigatinib, Entrectinib, Lenvatinib, Pazopanib, Sorafenib, Sunitinib). Local failure (LF) and radiation necrosis were determined radiographically with clinical impression (grade 2 (symptomatic) or higher (G2+)) and compared between different systemic agents.

RESULTS

The study included 95 patients with 310 metastases (SRS 246, SRT 64 metastases). Most common primary histologies were non-small cell lung cancer (36% 34/95), breast cancer (28% 27/95), and melanoma (16% 15/95). Overall survival at 1 and 2 years was 80% (76/95) and 55% (52/95), respectively. Median follow-up was 16.6 (range 3-91) months. Median tumor size was 7mm (range 1-75mm). Median number of brain metastases per patient was 2.5 (range 1-12). The G2+ radiation necrosis rate was 5.8% (18/310) while the LF rate was 9.7% (30/310) per metastasis. There was no significant difference in G2+ radiation necrosis by class of targeted therapy. Sixty-two percent (59/95) of patients experienced distant intracranial failure. Median intracranial progression free survival (PFS) was 8.0 (range 0.4-61.4) months.

CONCLUSION

Although heterogeneous, patients treated with SRS/SRT and ongoing CNS-active targeted systemic therapies have on average >6 month intracranial PFS and little evidence of significant toxicity. We observed <6% G2+ radiation necrosis for this cohort, and no particular class of agent was associated with a significantly higher rate of G2+ radiation necrosis.

Neurologic Events and Outcomes in Patients Receiving Proton and Photon Reirradiation for High Grade Non-Codeleted Gliomas

PURPOSE/OBJECTIVE(S)

Patients undergoing reirradiation (ReRT) for high grade glioma are at risk for tumor progression, pseudoprogression, and radiation necrosis. We investigated factors associated with neurologic events and disease control after re-irradiation with protons and photons at a single academic center.

MATERIALS/METHODS

We reviewed records and MRIs of patients receiving scanning beam proton (since center opening in 2016) and photon (since 2015) reirradiation in ≥10 fractions for grade 3 anaplastic astrocytoma (AA) and grade 4 glioblastoma (GBM), excluding 1p19q co-deleted oligodendrogliomas and extensive multifocal/leptomeningeal disease. The primary endpoint was time from ReRT to ≥ grade 2 pseudoprogression or radiation necrosis (PsP/RN, grade 2: moderate symptoms requiring outpatient steroids/bevacizumab, grade 3: severe symptoms leading to admission or surgical intervention). Dose was converted to EQD2 using a/b = 3. Cox proportional hazards model was used to calculate survival and time to PsP/RN.

RESULTS

A total of 53 patients were included (26 protons, 27 photons, median KPS 80). Patients receiving protons had more favorable features. Compared to the photons, the proton group was younger (48 vs. 58) and more likely to have AA (46% vs. 22%) and resection within 3 months (42% vs 26%). The proton group also had a longer interval from prior RT (57 vs. 39 months) and were less likely to receive bevacizumab at reRT (15% vs. 59%). CTV was 130 cc for protons vs 99 cc for photons, and most had active disease at time of ReRT identified on planning MRI (76% protons, 85% photons). Median OS was 10.5 months (14.1 months protons, 8.1 months photons), with time from initial RT the only significant factor on multivariate analysis. Median PFS was 9.4 months (9.8 months protons, 6.2 months photons). 9 patients (18%) had ≥ grade 3 PsP/RN (8 proton, 1 photon) and 21 patients (41%) had ≥ grade 2 PsP/RN (16 proton, 5 photon). Grade 3 events included 1 seizure (photon group), 1 hemorrhage, 1 thalamic stroke, 1 shunt placement, 1 re-resection, and PSP4 4 PsP/RN requiring admission. Protons were associated shorter time to ≥ grade 2 PsP/RN (4 months vs. not reached, p = 0.027). When accounting for bevacizumab use at time of reRT, the association between protons and PsP/RN lost significance but there remained a trend (grade 2, p = 0.095, HR 2.4; grade 3, p = 0.105, HR 5.8). CTV, MGMT status, EQD2, and interval from prior RT were not associated with PsP/RN.

CONCLUSION

High grade neurologic events were common in patients with predominantly active, unresected high grade gliomas receiving ReRT. Though ascertainment and survival bias are significant limitations, pseudoprogression and necrosis appeared to be more prominent in patients receiving protons. These results contribute to ongoing efforts to both optimize ReRT for high grade glioma and investigate biologic effects of proton therapy.

Practice patterns of pediatric total body irradiation techniques: A Children's Oncology Group survey

PURPOSE

The aim of this study was to examine current practice patterns in pediatric total body irradiation (TBI) techniques among xxx member institutions.

METHODS AND MATERIALS

Between Nov 2019 and Feb 2020 a questionnaire, containing 52 questions related to the technical aspects of TBI was sent to medical physicists at 152 xxx institutions. The questions were designed to obtain technical information on commonly used TBI treatment techniques. Another set of 9 questions related to the clinical management of patients undergoing TBI was sent to 152 xxx member radiation oncologists at the same institutions.

RESULTS

Twelve institutions were excluded because TBI was not performed in their institutions. A total of 88 physicists from 88 institutions (63% response rate) and 96 radiation oncologists from 96 institutions responded (69% response rate). The AP/PA technique was the most common (49 institutions - 56%); 44 institutions (50%) used the lateral technique and 14 institutions (16%) used volumetric modulated arc therapy (VMAT)/Tomotherapy. Mid-plane dose rates of 6-15 cGy/min were most commonly used. The most common specification for lung dose was the mid lung dose for both AP/PA (71%) and lateral (63%) techniques. All physician responders agreed with the need to refine current TBI techniques and 79% supported the investigation of new TBI techniques to further lower the lung dose.

CONCLUSION

There is no consistency in the practice patterns, methods for dose measurement and reporting of TBI doses among xxx institutions. The lack of a standardization precludes meaningful correlation between TBI doses and clinical outcomes including disease control and normal tissue toxicity. The xxx radiation oncology discipline is currently undertaking several steps to standardize the practice and dose reporting of pediatric TBI using detailed questionnaires and phantom-based credentialing for all xxx centers.

Results from the IRS-IV randomized trial of hyperfractionated radiotherapy in children with rhabdomyosarcoma--a report from the IRSG

PURPOSE

To evaluate the outcome and toxicity of hyperfractionated radiotherapy (HFRT) vs. conventionally fractionated radiotherapy (CFRT) in children with Group III rhabdomyosarcoma (RMS).

METHODS AND MATERIALS

Five hundred fifty-nine children were enrolled into the Intergroup Rhabdomyosarcoma Study IV with Group III RMS. Sixty-nine were ineligible for the analysis because of incorrect group or pathologic findings. Of the 490 remaining, 239 were randomized to HFRT (59.4 Gy in 54 1.1-Gy twice daily fractions) and 251 to CFRT (50.4 Gy in 28 1.8-Gy daily fractions). The age range was <1-21 years. All patients received chemotherapy. RT began at Week 9 after induction chemotherapy for all but those with high-risk parameningeal tumors who received RT during induction chemotherapy. The patient groups were equally balanced. The median follow-up was 3.9 years.

RESULTS

Analysis by randomized treatment assignment (intent to treat) revealed an estimated 5-year failure-free survival (FFS) rate of 70% and overall survival (OS) of 75%. In the univariate analysis, the factors associated with the best outcome were age 1-9 years at diagnosis; noninvasive tumors; tumor size <5 cm; uninvolved lymph nodes; Stage 1 or 2 disease; primary site in the orbit or head and neck; and embryonal histologic features (p = 0.001 for all factors). No differences in the FFS or OS between the two RT treatment methods and no differences in the FFS or OS between HFRT and CFRT were found when analyzed by age, gender, tumor size, tumor invasiveness, nodal status, histologic features, stage, or primary site. Treatment compliance differed by age. Of the children <5 years, 57% assigned to HFRT received HFRT and 77% assigned to CFRT received CFRT. Of the children >or=5 years, 88% assigned to both HFRT and CFRT received their assigned treatment. The reasons for not receiving the appropriate randomized treatment were progressive disease, early death, parent or physician refusal, young age, or surgery. The toxicity assessment revealed more mucositis with HFRT (66%) than with CFRT (46%) (p = 0.03) for the parameningeal patients, and more skin reactions (16%) and nausea/vomiting (13%) with HFRT than with CFRT (7% and 5%, respectively) for patients with nonparameningeal primary tumors (p = 0.03 and p = 0.02, respectively). The analysis by treatment actually received revealed a 5-year FFS rate of 73% and OS rate of 77%, with no difference between CFRT and HFRT. As well, there was no difference in FFS or OS between CFRT and HFRT when analyzed by age, gender, tumor size, tumor invasiveness, modal status, histology, stage or site of primary. The 5-year estimated cumulative incidence of failure for the irradiated patients was local, 13%; regional, 3%; and distant, 13%; with no differences between HFRT and CFRT. The 5-year local failure rate by site was orbit, 5%; head and neck, 12%; parameningeal, 16%; bladder/prostate, 19%; extremity, 7%; and all others, 14%. The 5-year regional failure rate was parameningeal,1%; extremity, 20%; and all others, 5%. The 5-year distant failure rate was orbit, 2%; head and neck, 6%; parameningeal, 11%; bladder/prostate, 15%; extremity, 28%; and all others, 17%.

CONCLUSIONS

HFRT, as given in this study, did not improve local/regional control, FFS, or OS compared with CFRT. The risk of local/regional failure was comparable to that of distant failure in children with Group III RMS. The standard of care for Group III RMS continues to be CFRT with chemotherapy.

Which patients with microscopic disease and rhabdomyosarcoma experience relapse after therapy? A report from the soft tissue sarcoma committee of the children's oncology group

PURPOSE

To identify which patients with rhabdomyosarcoma and microscopic residual disease (group II) are likely to not respond to therapy.

PATIENTS AND METHODS

Six hundred ninety-five patients with group II tumors received chemotherapy and 90% received radiation therapy on Intergroup Rhabdomyosarcoma Study (IRS)-I to IRS-IV (1972 to 1997). Tumors were subgrouped depending on the presence of microscopic residual disease only (subgroup IIa), resected positive regional lymph nodes, (subgroup IIb), or microscopic residual disease and resected positive regional lymph nodes (subgroup IIc).

RESULTS

Overall, the 5-year failure-free survival rate (FFSR) was 73%, and patients with embryonal rhabdomyosarcoma treated on IRS-IV fared especially well (5-year FFSR, 93%; n = 90). Five-year FFSRs differed significantly by subgroup (IIa, 75% and n = 506; IIb, 74% and n = 101; IIc, 58% and n = 88; P = .0037) and treatment (IRS-I, 68%; IRS-II, 67%; IRS-III, 75%; IRS-IV, 87%; P < .001). Multivariate analysis revealed positive associations between primary site (favorable), histology (embryonal), subgroup IIa or IIb, treatment (IRS-III/IV), and better FFSRs. Patterns of treatment failure revealed local failure to be 8%, regional failure, 4%, and distant failure, 14%. The relapse pattern noted over the course of IRS-I to IRS-IV shows a decrease in the systemic relapse rates, particularly for patients with embryonal histology, suggesting that improvement in FFSRs is primarily a result of improved chemotherapy.

CONCLUSION

Group II rhabdomyosarcoma has an excellent prognosis with contemporary therapy as used in IRS-III/IV, and those less likely to respond can be identified using prognostic factors: histology, subgroup, and primary site. Patients with embryonal rhabdomyosarcoma are generally cured, although patients with alveolar rhabdomyosarcoma or undifferentiated sarcoma, particularly subgroup IIc at unfavorable sites, continue to need better therapy.

Radiosurgery for patients with brain metastases: a multi-institutional analysis, stratified by the RTOG recursive partitioning analysis method

PURPOSE

To estimate the potential improvement in survival for patients with brain metastases, stratified by the Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis (RPA) class and treated with radiosurgery (RS) plus whole brain radiotherapy (WBRT).

METHODS AND MATERIALS

An analysis of the RS databases of 10 institutions identified patients with brain metastates treated with RS and WBRT. Patients were stratified into 1 of 3 RPA classes. Survival was evaluated using Kaplan-Meier estimates and proportional hazard regression analysis. A comparison of survival by class was carried out with the RTOG results in similar patients receiving WBRT alone.

RESULTS

Five hundred two patients were eligible (261 men and 241 women, median age 59 years, range 26-83). The overall median survival was 10.7 months. A higher Karnofsky performance status (p = 0.0001), a controlled primary (median survival = 11.6 vs. 8.8 months, p = 0.0023), absence of extracranial metastases (median survival 13.4 vs. 9.1 months, p = 0.0001), and lower RPA class (median survival 16.1 months for class I vs. 10.3 months for class II vs. 8.7 months for class III, p = 0.000007) predicted for improved survival. Gender, age, primary site, radiosurgery technique, and institution were not prognostic. The addition of RS boosted results in median survival (16.1, 10.3, and 8.7 months for classes I, II, and III, respectively) compared with the median survival (7.1, 4.2, and 2.3 months, p <0.05) observed in the RTOG RPA analysis for patients treated with WBRT alone.

CONCLUSION

In the absence of randomized data, these results suggest that RS may improve survival in patients with BM. The improvement in survival does not appear to be restricted by class for well-selected patients.

Routine brain imaging is unwarranted in asymptomatic patients with rhabdomyosarcoma arising outside of the head and neck region that is metastatic at diagnosis: a report from the Intergroup Rhabdomyosarcoma Study Group

BACKGROUND

To the authors' knowledge, the incidence of brain metastases at the time of diagnosis in children with metastatic rhabdomyosarcoma (RMS) arising outside the head and neck region is unknown, and routine imaging to identify metastatic brain involvement is costly.

METHODS

The authors retrospectively reviewed the results of computed tomography (CT) or magnetic resonance imaging (MRI) scans of the head, which was mandated by protocol, in patients with metastatic RMS arising outside the head and neck region who were enrolled on the fourth Intergroup Rhabdomyosarcoma Study (IRS-IV; 1991--1997).

RESULTS

Of 100 eligible patients with metastatic RMS arising outside the head and neck region, 56 (56%) underwent head CT (n = 51) and/or MRI (n = 11) scans. Seven of these 56 patients (12.5%) had abnormal scans. Three patients with physical findings suggesting head or neck pathology underwent imaging that confirmed the presence of metastases in bone (one patient), orbit (one patient), or lymph nodes (one patient). One patient who presented with seizures had imaging findings consistent with cerebral embolic infarctions. Of three asymptomatic patients, one had bone metastases that also were identified on skeletal survey and one had bone metastases in the base of the skull that were not identified on bone scan. The remaining asymptomatic patient had a retroperitoneal paraspinal tumor with spinal canal extension and subsequently developed leptomeningeal disease dissemination.

CONCLUSIONS

Brain metastases are uncommon at the time of initial diagnosis of metastatic RMS arising outside the head and neck region, and the majority of abnormalities detected on head CT or MRI scans are evident clinically or on other imaging studies. Patients with clinical findings suggesting intracranial pathology and those with paraspinal tumors may benefit from brain imaging, but cost savings may be realized by foregoing imaging in patients without these features.

Modification of a linear accelerator table top for non-coplanar conformal brain radiotherapy

The use of non-coplanar conformal therapy necessitates the use of unusual beam projections that may not be accomplished with a conventional linear accelerator table top. Modification of the table top can increase the available combinations of gantry and couch rotation. A standard Philips table top, supplied with an SL 75-5 linear accelerator, was modified to increase available combinations of gantry and couch rotation. This was accomplished by shortening the length and decreasing the width of the table top. The modified table top increases the combinations of gantry and couch angles significantly, simplifying the delivery of non-coplanar conformal therapy without significant compromise to routine treatment. The modification of a standard linear accelerator table top has increased the available combinations of gantry and couch rotation to accommodate non-coplanar conforrmal radiotherapy.

Clinical oncology clerkship for third-year medical students

BACKGROUND

A two-week elective clerkship in clinical oncology is offered to third-year medical students.

METHODS

Two students at a time participated in the rotation and spent time with attendings in a one-to-one setting in outpatient clinics in the cancer specialties. The students also attended multidisciplinary tumor boards. Grand rounds, peer review conferences, and problem-case conferences were attended by the students as well. The students met with an attending for one-hour, twice-per-week to discuss pertinent oncologic cases and problems. The exposure to clinical oncology for two weeks is intended to educate the students relative to the presentation, evaluation, treatment, prognosis, and follow-up for a variety of cancers.

RESULTS

The rotation has been highly successful as measured by its popularity and by consistently high course evaluations from the medical students.

CONCLUSION

The overall quality of the learning experience for the rotation has been rated by the students as the highest among all courses in their four-year curriculum.

Issues in the local control of rhabdomyosarcoma

BACKGROUND

Rhabdomyosarcoma (RMS) is a heterogeneous disease consisting of several different histologies arising from a variety of anatomic sites. Approximately half of the children who die of this tumor have failure at the primary site of involvement, making local control an important component of therapy.

PROCEDURE

Published literature and newly analyzed data from the Intergroup Rhabdomyosarcoma Study Group (IRSG) regarding local control of RMS were reviewed. Information regarding the role of various local control modalities for different primary disease sites is presented along with new directions for clinical research.

RESULTS

Local control rates for RMS average 80% for group III tumors, with large variations seen for different anatomic sites. Important gains in functional outcome for certain sites such as gynecologic system and bladder/prostate have been achieved by optimizing the use of the various treatment modalities. Local control at other sites such as the chest and extremities remains a problem.

CONCLUSIONS

Advances in surgical and radiotherapy techniques coupled with multiagent chemotherapy are providing improved local control with decreasing morbidity. Optimal outcome is dependent on close collaboration between surgical, radiotherapy, and pediatric oncology specialists.

Benefit of intensified therapy for patients with local or regional embryonal rhabdomyosarcoma: results from the Intergroup Rhabdomyosarcoma Study IV

PURPOSE

To compare failure-free survival (FFS) and survival for patients with local or regional embryonal rhabdomyosarcoma treated on the Intergroup Rhabdomyosarcoma Study (IRS)-IV with that of comparable patients treated on IRS-III.

PATIENTS AND METHODS

Patients were retrospectively classified as low- or intermediate-risk. Low-risk patients were defined as those with primary tumors at favorable sites, completely resected or microscopic residual, or orbit/eyelid primaries with gross residual disease and tumors less than 5 cm at unfavorable sites but completely resected. Intermediate-risk patients were all other patients with local or regional tumors.

RESULTS

Three-year FFS improved from 72% on IRS-III to 78% on IRS-IV for patients with intermediate-risk embryonal rhabdomyosarcoma (P =.02). Subset analysis revealed two groups that benefited most from IRS-IV therapy. FFS at 3 years for patients with resectable node-positive or unresectable (group III) embryonal rhabdomyosarcoma arising at certain favorable sites (head and neck [not orbit/eyelid or parameningeal] and genitourinary [not bladder or prostate]) improved from 72% on IRS-III to 92% on IRS-IV (P =.01). Similarly, 3-year FFS for patients with completely resected tumor or with only microscopic disease remaining (group I or II) at unfavorable sites improved from 71% on IRS-III to 86% on IRS-IV (P =.04). Only patients with unresectable embryonal rhabdomyosarcoma (group III) at unfavorable sites had no improvement in outcome on IRS-IV (3-year FFS for IRS-III and IRS-IV, 72% and 75%, respectively; P =.31).

CONCLUSION

IRS-IV therapy benefited certain subgroups of patients with intermediate-risk embryonal rhabdomyosarcoma. A doubling of the intensity of cyclophosphamide (or ifosfamide equivalent) dosing per cycle between IRS-III and IRS-IV is thought to be a key contributing factor for this improvement.

Permanent iodine-125 interstitial implants for the treatment of recurrent glioblastoma multiforme

OBJECTIVE

Brachytherapy with temporary implants may prolong survival in patients with recurrent glioblastoma multiforme (GBM), but it is associated with relatively high costs and morbidity. This study reports the time to progression and survival after permanent implantation of iodine-125 seeds for recurrent GBM and examines factors predictive of outcome.

METHODS

Forty patients with recurrent GBM were treated with maximal resection plus permanent placement of iodine-125 seeds into the tumor bed. A total dose of 120 to 160 Gy was administered, and patients were followed up with magnetic resonance imaging scans every 2 to 3 months.

RESULTS

Actuarial survival from the time of implantation was 47 weeks, with 7 of 40 patients still alive at a median of 59 weeks after implantation. Survival was significantly better for patients younger than 60 years, and a trend for longer survival was demonstrated with gross total resection and tumors with a low MIB-1 (a nuclear antigen present in all cell cycles of proliferating cells) staining index. Median time to progression was 25 weeks and, on multivariate analysis, was favorably influenced by gross total resection and patient age younger than 60 years. After implantation, 27 of 30 patients with failure had a local component to the failure. No patient developed symptoms attributable to radiation necrosis or injury.

CONCLUSION

Permanent iodine-125 implants for recurrent GBM result in survival comparable with that described in previous reports on temporary implants, but with less morbidity. Results are most favorable for patients who are younger than 60 years, and who undergo gross total resection. Despite this aggressive treatment, most patients die as a consequence of locally recurrent disease.

Indications for radiotherapy and chemotherapy after complete resection in rhabdomyosarcoma: A report from the Intergroup Rhabdomyosarcoma Studies I to III

PURPOSE

To evaluate the outcome of patients with rhabdomyosarcoma (RMS) treated with complete surgical resection and multiagent chemotherapy, with or without local radiotherapy (RT).

PATIENTS AND METHODS

Four hundred thirty-nine patients with completely resected (ie, group I) RMS were further treated with chemotherapy (vincristine and actinomycin D +/- cyclophosphamide, doxorubicin, and cisplatin) on Intergroup Rhabdomyosarcoma Studies (IRS) I to III between 1972 and 1991. Eighty-three patients (19%) also received local RT as a component of initial treatment.

RESULTS

Eighty-six patients relapsed (10-year failure-free survival [FFS] 79%, overall survival 89%). Six percent of failure sites were local, 6% were regional, and 7% were distant. Poor prognostic factors were tumor size greater than 5 cm, alveolar or undifferentiated histology, primary tumor sites other than genitourinary, and treatment on IRS-I or II. For patients with embryonal RMS who were treated with RT, there was a trend for improved FFS but no difference in overall survival. On IRS-I and II, patients with alveolar or undifferentiated sarcoma who received RT compared with those who did not receive RT had greater 10-year FFS rates (73% v 44%, respectively; P =.03) and overall survival rates (82% v 52%, respectively; (P =.02). Such patients who received RT on IRS III also benefited more than those who did not receive RT (10-year FFS, 95% v 69%; P =.01; overall survival, 95% v 86%; P =.23).

CONCLUSION

Patients with group I embryonal RMS have an excellent prognosis when treated with adjuvant multiagent chemotherapy without RT. Patients with alveolar RMS or undifferentiated sarcoma fare worse; however, FFS and overall survival are substantially improved when RT is added to multiagent chemotherapy (IRS-I and II). The best outcome occurred in IRS-III, when RT was used in conjunction with intensified chemotherapy.

What comprises appropriate therapy for children/adolescents with rhabdomyosarcoma arising in the abdominal wall? A report from the Intergroup Rhabdomyosarcoma Study Group

PURPOSE

The aim of this study was to define clinical features and determine the best therapy for patients with rhabdomyosarcoma (RMS) of the abdominal wall.

METHODS

We examined the demographic, clinical features, therapy (especially surgical), and outcome of 34 patients. Patients received combination chemotherapy after complete surgical resection (group I, n = 14; 41%); resection with microscopic residual followed by local irradiation (RT; group II, n = 8; 24%); partial resection or biopsy only plus RT with gross locoregional residual tumor (group III, n = 4; 12%); or biopsy only plus RT with metastatic disease (group IV, n = 8; 24%). Patients with group I or group II tumors had undergone partial abdominal wall resection (ie, involved muscle only with preservation of peritoneum, n = 11) or complete abdominal wall resection (n = 7). Four additional patients had groin lesions.

RESULTS

Thirty-four children or adolescents with abdominal wall RMS (about 1% of all patients) were treated on Intergroup Rhabdomyosarcoma Study I (IRS-I) through IRS-IV. Overall, adolescents comprised 14 of 34 eligible patients (41%), and 10 of 14 (71%) adolescents had alveolar or undifferentiated tumors versus 8 of 20 (40%) younger children (P= .07). Failure-free survival (FFS) rate and survival rate at 5 years was 65%. Treatment outcome was poorer for patients with group III-IV tumors (P = .01), adolescents (P = .09) and patients with alveolar or undifferentiated sarcomas (P = .12).

CONCLUSION

Patients with localized tumors appear to fare better if they undergo complete abdominal wall resection (long-term survival rate, 100%) versus partial resection (long-term survival rate, 62% [P = .12]).

Treatment of patients with acute lymphoblastic leukemia with bulky extramedullary disease and T-cell phenotype or other poor prognostic features: randomized controlled trial from the Children's Cancer Group

BACKGROUND

Children with acute lymphoblastic leukemia with multiple poor prognostic factors and who have a lymphomatous mass at diagnosis, whether of T- or non-T-immunophenotype, are at increased risk of short term remission and extramedullary recurrence, and are in need of better therapies.

METHODS

Six hundred and ninety-four eligible patients ranging in age from 1-20 years were entered on the study. Sixty-five percent of the patients had T-cell immunophenotype. Of these, 678 were randomized to one of four regimens: Regimen A: Berlin-Frankfurt-Munster (BFM) 76/79; Regimen B: LSA2-L2 with cranial irradiation; Regimen C: LSA2-L2 without cranial irradiation; and Regimen D: the New York (NY) regimen.

RESULTS

Complete remission was induced in 97% of patients. The overall event free survival (EFS) +/- the standard deviation was 60 +/- 4% 6 years after diagnosis, in contrast to 36 +/- 6% in a comparable historic group. The EFS of the 371 T-cell patients was 62 +/- 7%. EFS was best on the NY (67 +/- 7%) and the BFM (67 +/- 6%) arms. These were significantly better than the EFS on the 2 LSA-L2 regimens, with an EFS of 53 +/- 8% (Regimen B) and 42 +/- 11% (Regimen C) (P = 0.03 and 0.0003 for NY vs. Regimen B and NY vs. Regimen C; P = 0.01 and 0.0001 for BFM vs. Regimen B and BFM vs. Regimen C). Regimen C had a 3-fold greater central nervous system (CNS) recurrence rate than the identical chemotherapy Regimen B (16 +/- 5% vs. 6 +/- 4%; P = 0.02), although the difference in overall EFS did not reach the required level for significance. Testicular recurrence varied from 2-8% in comparison with 20% in the historic group. EFS was not influenced by age, gender, CNS disease at diagnosis, morphology, or immunophenotype. In addition to treatment regimen and early response rate, initial leukocyte count, hemoglobin level, liver, spleen, and lymph node enlargement, and the presence of a mediastinal mass had univariate prognostic influence on EFS. In multivariate analysis, only the kinetics of response, leukocyte count (unfavorably, P < 0.0001), and mediastinal mass status (favorably, P = 0.01) were prognostic.

CONCLUSIONS

The adverse prognostic implications of lymphomatous ALL can be minimized by the NY and BFM regimens. Cranial irradiation resulted in better CNS disease control when added to the LSA2-L2 regimen, but did not improve the overall disease free survival. With improved systemic chemotherapy, there was no excess of lymph node, testicular, or other local recurrence without prophylactic irradiation to sites of initial bulk disease or to the testes.

Stereotactic radiosurgery for the treatment of brain metastases. Results of a single institution series

BACKGROUND

Stereotactic radiosurgery is being used with increasing frequency for the treatment of brain metastases. Optimal patient selection and treatment factors continue to be defined. This study provides outcome data from a single institutional experience with radiosurgery and identifies parameters that may be useful for the proper selection and treatment of patients.

METHODS

Eighty-four patients underwent stereotactic radiosurgery for brain metastases between September 1989 and November 1995. Seventy-nine patients (93%) were treated at recurrence after previous whole brain radiotherapy. Patients had between 1 and 6 lesions treated with a median minimum tumor dose of 1600 centigrays (cGy). Thirty-eight patients (45%) had active extracranial disease at the time of radiosurgery.

RESULTS

Median survival for the entire group was 43 weeks from the date of radiosurgery and 71 weeks from the original diagnosis of brain metastases. Patients with 1 or 2 metastases had significantly improved survival compared with patients with > or = 3 metastases (P = 0.02), and patients without active extracranial tumor survived longer than those with extracranial disease (P = 0.03). Median time to failure for 145 evaluable lesions was 35 weeks. Local control was significantly improved for radiosurgery doses of > 1800 cGy, and for melanoma histology.

CONCLUSIONS

These results are comparable to reports of patients treated with resection and significantly superior to results observed after whole brain radiotherapy. The authors conclude that stereotactic radiosurgery is an effective, low risk treatment for extending the survival of patients with recurrent brain metastasis. Although survival is best for patients with < or = two lesions and no active extracranial disease, selected patients with > two lesions or active extracranial tumor may benefit as well.

Ewing's sarcoma of soft tissues in childhood: a report from the Intergroup Rhabdomyosarcoma Study, 1972 to 1991

PURPOSE

One hundred thirty of 2,792 patients (5%) registered on three Intergroup Rhabdomyosarcoma Study clinical trials (IRS-I, -II, and -III) from 1972 to 1991 had an extraosseous Ewing's sarcoma (EOE). We report here the results of multimodality therapy for this tumor.

PATIENTS AND METHODS

The 130 patients were less than 21 years of age; 70 (54%) were males. Primary tumor sites were on the trunk in 41 patients, an extremity in 34, the head/neck in 23, the retroperitoneum/pelvis in 21, and other sites in 11. One hundred fourteen patients had no metastases at diagnosis. In 21 patients, the tumor was completely resected; in 30, the localized or regional tumor was grossly resected, and in 63 patients, grossly visible sarcoma was left behind. Sixteen patients (12%) had distant metastases at diagnosis. All patients were given multiagent chemotherapy and most received irradiation (XRT); none were treated with bone marrow transplantation.

RESULTS

One hundred seven patients (82%) achieved a complete response. At 10 years, 62%, 61%, and 77% of the patients were alive after treatment on IRS-I, IRS-II, or IRS-III therapeutic protocols, respectively, similar to figures obtained in all IRS patients. At last follow-up evaluation, 42 patients had died of progressive tumor and one of infection. Survival at 10 years was most likely for patients with tumor that arose in the head and neck, extremities, and trunk, and for those who underwent grossly complete tumor removal before initiation of chemotherapy. For patients with localized, gross residual tumor, adding doxorubicin (DOX) to the combination of vincristine, dactinomycin, cyclophosphamide (VAC), and XRT did not significantly improve survival in 39 patients (62% alive at 10 years) compared with that of 24 patients treated with VAC and XRT without DOX (65% alive at 10 years, P = .93).

CONCLUSION

This series indicated that EOE in children is similar to rhabdomyosarcoma (RMS) in its response to multimodal treatment. No benefit was apparent from the addition of DOX to VAC chemotherapy in patients with gross residual EOE.

The argument for conservative, delayed surgery in the management of prostatic rhabdomyosarcoma

Exenteration is no longer required for most patients who have rhabdomyosarcoma (RMS) of the prostate. This site comprised only about 5% of newly diagnosed cases in the IRS-III (1984-1991). The mean age at the time of diagnosis was 5.3 yrs (range, 0 to 19 years). Most tumors were relatively large, had embryonal histology, and were clinically localized but unresectable without major loss of organ function. The 44 patients with group III tumors (gross residual disease) were treated according to the IRS-III protocol. Forty-three of them underwent biopsy only, and one patient had subtotal resection as the initial procedure. The average number of surgical procedures per patient was two (range, one to five). Six of the 44 patients had no additional surgery. The second-look procedures performed in the other 38 patients included exenteration (14), prostatectomy (7), cystoscopic/perineal needle biopsy (8), laparotomy with biopsy (6), and subtotal excision with bladder salvage (3). Additional surgery was required for four patients, for evaluation of a residual mass, postoperative fistula, ureteral stricture, or small bowel obstruction. Six patients with relapse or residual disease underwent additional chemotherapy and late exenteration (3), prostatectomy (1), or biopsy (2). Four of the six have been cured, one is in treatment for a second malignancy, and the other has residual disease after exenteration. Thirty-six of the 44 patients with group III tumors have been cured (minimum follow-up period, 6 years; range, 6 to 11 years), compared with 23 of the 47 in IRS-II (1978-1984) (P = .001). Two of the six deaths in this group were caused by infection. The bladder salvage rate for those cured of their disease also was better (64% v 57% for IRS-II). The two patients with group IIA tumors were cured by gross primary excision, local radiotherapy, and vincristine and actinomycin therapy. By contrast, all patients with metastatic disease (group IV) died of the tumor. Conservative, delayed surgery, performed after intensive chemotherapy with or without radiotherapy, yields a better cure rate while maintaining a high rate of bladder salvage in children with group III prostatic RMS.

Cytoreduction and prognosis in acute lymphoblastic leukemia--the importance of early marrow response: report from the Childrens Cancer Group

PURPOSE

To quantify the residual marrow lymphoblast fraction that best defines patients at high risk for relapse, and the optimal time for assessment during remission induction.

PATIENTS AND METHODS

The residual lymphoblast percentage was evaluated on day 7 (n = 220) and day 14 (n = 205) during a four- or five-drug induction in patients with poor prognostic factors. The rate of cytoreduction was related to event-free survival (EFS) and other factors.

RESULTS

On the New York (NY) regimen, 68%, 14%, and 18%, and on the Berlin-Frankfurt-Munster (BFM) regimen, 56%, 15%, and 29% of patients had M1 (< 5% blasts), M2 (5-25%), or M3 (> 25%) responses on day 7 (P = .075). On day 14, the corresponding values were 87%, 6%, 7% on NY and 84%, 8%, 8% on BFM. For patients who achieved remission by day 28 and a day-7 marrow rating of M1, M2, or M3, the 6-year EFS rate was 78%, 61%, and 49% (P < .001). The day-14 ratings predicted for a 72%, 32%, or 40% EFS (P < .001). Patients with 5% to 10% blasts day 7 had three times as many events as those with less than 5% and had no better EFS than those with 11% to 25% blasts. Patients with a WBC count more than 200,000/microL at diagnosis and an M1 day 7 marrow had an EFS rate of 69%, while for those with M2 or M3, the EFS rate was 41%. Day-7 marrow had greater prognostic significance than the day-14 evaluation. For slow responders on day 7, the day-14 marrow provided additional information. EFS for patients who achieved M1 by day 14 was 65%. EFS decreased to 20% for those still M2 or M3 on day 14. Day-7 and -14 evaluations had significance for patients of all ages and WBC levels.

CONCLUSION

Marrow aspiration on day 7 of therapy provided more useful information than that on day 14. However, day-14 marrow provided additional information for patients with a poor day-7 response. The rate of cytoreduction is a powerful, independent prognostic factor that can identify patients with a slow early response who are at risk for a short remission duration.

A method to reduce systematic spatial shift associated with magnetic resonance imaging

To reduce the chemical shifts during magnetic resonance (MR) imaging, the authors replaced the petroleum gel in the Brown-Roberts-Well (BRW) MR localizer with chromium chloride. Computed tomography and MR scans were obtained of a phantom skull containing objects with known spatial coordinates. A 2-to 3-mm systematic spatial shift in the frequency-encoded direction was observed with petroleum gel, but not with CrCl3. Results were verified by reconstructing the three-dimensional spatial location of each object using X-Knife computer software. The authors conclude that spatial localization is more accurate with a CrCl3-filled than a petroleum-filled BRW-MR localizer.

Immunology of delayed food allergy

Studies here and abroad are stockpiling evidence that immunoglobulin E explains only a small part of food allergy. Involvement of the entire immune system is evident if the more prevalent delayed-type food allergy is to be explained. To adequately diagnose food hypersensitivity a testing technique must be used that identifies delayed food allergy, such as the patch test here described, along with a test that diagnoses immediate immunoglobulin E-mediated food allergy.

Adult choroidal vein of Galen malformation

We report staged embolization and stereotactic radiation in a true adult choroidal vein of Galen malformation. Management dilemmas and their resolutions are also discussed.

Ionizing radiation therapy in dermatology

The introduction of new surgical techniques and other therapeutic modalities has markedly influenced the use of ionizing radiation therapy in dermatology. X-rays and electron beams are now used only for a limited number of indications in carefully selected patients. Since surgical approaches have gained popularity in the treatment of skin tumors, not all dermatologists are familiar with the benefits of ionizing radiation for patients with cutaneous neoplasms and certain other skin disorders. This article reviews modern indications for radiation therapy in dermatology. Important physical and biologic factors, radiation side effects, radiation protection measures, and therapeutic results will also be discussed. Although the use of radiotherapy in dermatology has in large part been supplanted in recent years by other forms of treatment, ionizing radiation continues to be an essential therapeutic alternative for many cutaneous tumors and some skin diseases. It is important to be familiar with the principles of radiotherapy so that optimal therapy can be selected for individual patients.

The role of radiation therapy in the treatment of acute lymphoblastic leukemia with lymphomatous presentation: a report from the Childrens Cancer Group

PURPOSE

Childrens Cancer Group 123 was a trial of intensive multidrug chemotherapy as well as cranial irradiation and bulk disease irradiation in children with acute lymphoblastic leukemia with lymphomatous presentation (bulk disease and either T-cell phenotype, high white blood count, or absence of anemia), a poor prognostic group with an increased risk of central nervous system (CNS) and other extramedullary recurrence.

METHODS AND MATERIALS

Three hundred eight patients without CNS disease were randomized among three regimens: A--BFM chemotherapy (designed for high risk ALL patients) with 1800 cGy cranial irradiation; B--LSA2L2 chemotherapy (designed for non-Hodgkins lymphoma patients) with 1800 cGy cranial irradiation and 1500 cGy to nonabdominal bulk disease; C--Reg B without cranial irradiation. All patients received intrathecal methotrexate throughout therapy. Radiation treatment records were reviewed.

RESULTS

With a minimum 52-month follow-up, Regimen B and C patients had 5-year actuarial CNS relapses of 7% and 17% (p = 0.01) and event-free survivals of 53% and 39% (p = 0.04). Patients with white blood count < 50,000/mm3 did not benefit from cranial irradiation. Regimen A patients had the same CNS relapse rate as Regimen B patients but an improved event-free survival. Regimen B and C patients with large mediastinal masses who received their assigned chest radiation had a lower event rate than those who did not (p = 0.06). Patients whose cranial fields did or did not encompass the entire meningeal surface had equivalent CNS relapse rates.

CONCLUSION

Patients treated with LSA2L2 chemotherapy, a less than optimal regimen, benefited from cranial and mediastinal irradiation. Compliance with radiation volume guidelines was not essential for patients to receive the benefit of cranial irradiation.

Design of a cap for radioshielding during treatment with interstitial 125I brain implants

A practical radiation shielding cap has been constructed for use during 125I brain implants. The cap is comfortable enough to be worn continuously during a 6-day implant and provides complete shielding from the implanted radioactive sources.

Phase II study of pentostatin and intermittent high-dose recombinant interferon alfa-2a in advanced mycosis fungoides/Sézary syndrome

PURPOSE

This phase II study was undertaken to assess the efficacy and toxicity of alternating administration of pentostatin (deoxycoformycin [DCF]) and interferon alfa-2a (IFN) in patients with advanced or refractory mycosis fungoides (MF) or the Sézary syndrome (SS).

PATIENTS AND METHODS

Forty-one patients underwent therapy with alternating cycles of DCF 4 mg/m2 intravenously (IV) days 1 through 3 and IFN 10 million U/m2 intramuscularly (IM) day 22, and 50 million U/m2 intramuscularly (IM) days 23 through 26. Twenty-nine patients had not responded to prior chemotherapy or total-skin electron-beam irradiation (TSEB), six had not responded to topical therapies, and six had no previous treatment.

RESULTS

Two patients achieved a complete response (CR) and 15 achieved a partial response (PR), for an overall response rate of 41% (95% confidence interval, 26% to 58%). No responses were observed in the seven patients with visceral involvement. The median progression-free survival of patients who responded was 13.1 months. IFN-related constitutional symptoms were reported in 39% of patients; severe toxicities included cardiomyopathy in one patient, acute and chronic pulmonary dysfunction in four, and reversible mental status changes in two. Seven patients developed herpes zoster during therapy and six had staphylococcal bacteremia.

CONCLUSION

These results suggest that the combination of DCF and IFN is an active regimen in MF patients without visceral involvement.

Topical mechlorethamine in the treatment of mycosis fungoides. Uniformity of application and potential for environmental contamination

Topical mechlorethamine hydrochloride is commonly used in the treatment of mycosis fungoides and has been formulated in both aqueous and ointment vehicles. Two concerns regarding the topical application of mechlorethamine hydrochloride relate to the adequacy of skin coverage that can be attained by the patient and the extent to which others in the patient's household might be exposed to the drug. In this study six patients applied either aqueous or ointment vehicles containing a fluorescent dye. Subsequent examination of the skin under a Wood's lamp revealed a significant percentage of body surface area to be missed during application; several areas were noted to be missed most commonly. These observations have led to specific alterations in instructions given to patients regarding drug application. Examination of the surrounding environment showed minimal evidence of contamination.

Concurrent radiotherapy and chemotherapy for locally advanced non-small-cell cancer of the lung. Report of a clinical trial and review of the literature

A prospective nonrandomized phase II study was begun in 1985 using concurrent split-course radiation and chemotherapy in the treatment of locally advanced non-small-cell cancer of the lung. Patients were treated with 3,000 cGy of radiation in 15 fractions to the chest, together with 100 mg/m2 cisplatin on day 1 and 1,000 mg/m2/day 5-fluorouracil infusion on days 1-4. The radiation and chemotherapy were then repeated after a 1-week break. Twenty-one patients were treated, with five patients having a complete response and nine patients having a partial response for an overall response rate of 67%. With a minimum of 24 months follow-up, five patients remain alive. Median survival for the entire group is 11.6 months. The toxicity of the treatment regimen was acceptable. These results do not differ significantly from survivals of similar patients treated with radiation alone, including a series from our own institution. The literature on concurrent chemotherapy and radiation is reviewed and possible future approaches to this tumor are discussed.

A technique for delivery of total body irradiation for bone marrow transplantation in adults and adolescents

With the increasing use of bone marrow transplantation for cancer, total body irradiation is becoming a more commonplace procedure in many of the larger centers across the country. The technical difficulties in delivering homogenous doses of radiation to the whole body are significant and involve many factors such as creation of a homogeneous, "flat" beam of radiation, and dealing with variations in patient thickness and tissue homogeneity, particularly in the lung. In addition, techniques must be used to safely and efficiently deal with patients who are usually very ill and require long treatment times. Although there is often an advantage in terms of dosimetry to using an AP/PA treatment technique, many institutions use parallel opposed lateral beams because of equipment and facility limitations. A technique has been devised that enables total body irradation to be given by an AP/PA technique using equipment available in many radiotherapy departments. Patients are supported in an upright position during treatment by means of a modified harness attached to the ceiling of the treatment room. Lung compensators are fixed to individually fitted "vests," allowing the patient moderate amounts of movement during treatment while maintaining the position of the compensator relative to the lungs. Thermoluminiscent dosimeter (TLD) dose measurements in a phantom indicate that this system can deliver accurate and homogeneous doses to lung tissue, while allowing a good degree of patient comfort and safety during the long treatment times that are required.

Management of radiation-induced moist skin desquamation using hydrocolloid dressing

Moist skin desquamation has been of concern to radiation oncologists, nurses and patients since the inception of this mode of therapy. As radiation treatment machines became more sophisticated, severe reactions became less of a problem. However, with the increasing use of chemotherapy and radiation as combined modalities, moist skin reaction is occurring with greater frequency. A noncomparative study of 20 patients using a hydrocolloid occlusive dressing (Duoderm) was initiated. The purpose of the study was to determine whether moist occlusive healing would be beneficial. The dressing was evaluated on the basis of healing time, safety, wound temperature, bacterial growth, and comfort. Data were collected using photographs, bacterial cultures, temperature probes, and patient evaluations. Eighteen patients completed the study. All patients' skin reactions healed. There were no wound infections evident. Mean healing time was 12 days, with mean wound temperature relative to body core -0.8 degree C on day 1 and -1.2 degrees C on the healed site. Patient results on comfort were: 8 of 18 excellent, 7 of 18 good, 3 of 18 fair, and 0 of 18 poor. The results of this study indicate that a hydrocolloid occlusive dressing can be effective in the healing process of moist skin reaction that is due to radiation therapy.

Patch tests demonstrating immune (antibody and cell-mediated) reactions to foods

For decades food allergists have sought a simple, inexpensive test for food allergy. Intradermal tests of aqueous material have not proved reliable. When positive, they are probably only 10% accurate. The newer laboratory tests for food allergy are expensive and highly sophisticated. They are impractical for use in the laboratories of practicing allergists with whom individuals with a potential food allergy are most liable to consult. The RAST is capable of identifying only Type I of the Gell-Coombs' reaction classification. Since 1980, a patch test of individual foods suspended in dimethylsulfoxide has been used as a screen for sensitivity to foods. Controlled clinical studies suggest this might prove to be a valuable test for food allergy. Immune studies appear to confirm the accuracy and reliability of this inexpensive test. No systemic reactions have been observed in the 400 patients tested indicating it to be a safe procedure.

Incorporation of patient immobilization, tissue compensation and matchline junction technique for three-field breast treatment

A protocol for the treatment of the intact breast was developed to maximize dose homogeneity and reproducibility. This protocol uses patient and breast immobilization, three-dimensional tissue compensators, and a technique for geometric matching of fields when the supraclavicular area is treated. A series of phantom measurements and analysis of patient port films was performed to evaluate dose homogeneity and reproducibility using this technique, and the potential adverse effect of loss of skin sparing from the immobilization device was investigated. Dose homogeneity throughout the phantom breast was within +/- 6% of the prescribed central axis dose, and homogeneity at the supraclavicular match line was +/- 10%. This represented a significant improvement over techniques not using tissue compensation or geometrically matched fields. Reproducibility of patient treatments was not significantly improved from previous non-immobilized treatment techniques, but there was no loss of skin sparing from the device, and other advantages of immobilization were observed. Details of the protocol are discussed together with changes that are currently being made to improve the results obtained thus far.

Prevention of stomal recurrence in patients requiring emergency tracheostomy for advanced laryngeal and pharyngeal tumors

Since 1976, patients requiring emergency tracheostomy for advanced laryngeal and hypopharyngeal cancer at the University of Cincinnati have been treated with a short course of prelaryngectomy radiation in an attempt to decrease the incidence of stomal recurrence. Twenty-one patients were treated after emergency tracheostomy with a course of radiation that usually consisted of 20 Gy in five fractions followed by laryngectomy 1 or 2 days later. Most patients also received postoperative radiotherapy of some type. The follow-up of 18 evaluable patients revealed only two (11%) stomal recurrences--a quite acceptable rate for this high-risk population. Overall, however, local recurrences were seen in ten patients (56%), which is higher than reported in most series of similar tumors. The most likely explanation for this seems to be that the short course preoperative radiation prevented the administration of adequate postoperative radiation for residual disease, which was usually present. An alternative treatment policy would be a planned course of moderate- to high-dose postoperative radiation, which could sterilize tumor in the entire locoregional area including the stoma.

The distribution of power and heat produced by interstitial microwave antenna arrays: II. The role of antenna spacing and insertion depth

The distribution of power and temperature generated by 915 MHz interstitial microwave antenna arrays was studied in static muscle-equivalent phantoms and both perfused and non-perfused canine thigh muscle. These arrays, which would form the geometric basis of larger volume implants, consisted of four parallel antennas oriented such that transverse to their long axes they formed the corners of a square. Arrays with 2 and 3 cm sides were compared at various depths of insertion where the nodes for all four antennas were coincident at the same depth. The position relative to the antenna nodes of the maximum power and highest temperature within the array volume varied with the depth of insertion of the antennas. Though power dropped rapidly distal to the nodes at all depths, a shift in the location of the maximum power proximal to the nodes resulted in an increase in the effective heating volume at certain insertion depths. For 2 cm array spacing the highest power and temperature were measured along the central axis of the array at all insertion depths. However, arrays using 3 cm spacing generated their maximum power adjacent to the antennas with only 50% of this level occurring along the central axis. When the temperature produced by 3 cm arrays was measured in phantoms midway through simulated 30-minute hyperthermia treatments, the effect of thermal conduction on the temperature distribution was evident. Though power was only 50% centrally, the highest temperatures occurred there. This same pattern of central heating occurred in perfused canine muscle demonstrating the importance of conductive and convective heat redistribution in reducing thermal gradients within the array volume.

The distribution of power and heat produced by interstitial microwave antenna arrays: I. Comparative phantom and canine studies

To adequately plan and administer localized hyperthermia with interstitial microwave antennas, the thermal distribution patterns generated by such antennas must be characterized. This study evaluated the performance of single node 915 MHz antennas operating either alone or as a 2 cm square array of four parallel antennas using both muscle-equivalent phantoms and canine thigh muscle. Two types of measurements were compared. Specific absorption rate (SAR), where temperature increases resulting from short duration microwave pulses were used to define power distribution, and temperature gradients during simulated hyperthermia treatments. SAR measurements in phantoms were comparable to those obtained in non-perfused canine muscle demonstrating the usefulness of the phantom for these measurements. For a single antenna there was a rapid decrease in power radially which resulted in a steep thermal gradient at distances within 0.5 cm. However, the power generated by a four-antenna array was highest along its central axis and declined to approximately 50% near the antennas at the array periphery. Along the central axis of the array power decreased most rapidly distal to the antenna nodes. The distribution of temperature measured during simulated hyperthermia treatments in phantoms paralleled the SAR distribution and was comparable to the temperature gradient observed in perfused canine muscle, suggesting that phantoms could be used to predict temperature distributions in resting muscle tissue.

The facial reflex of allergy

The facial reflex, originally described by Franz Chvostek, is shown to be of value in allergy by assessing the relative irritability of muscle tissue (cardic, smooth, skeletal) and the effect of certain drugs frequently used by allergists upon them.