Concurrent platinum-based chemotherapy with intensity modulated radiation therapy (IMRT) for locally advanced squamous cell carcinoma of the head and neck (SCCHN): A retrospective single institution analysis

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Background: Randomized clinical and meta-analysis data support the use of concurrent chemoradiation for treatment of locally advanced (SCCHN). IMRT is increasingly being used in treating SCCHN. We present outcome data from Emory University Winship Cancer Institute (WCI) with concurrent platinum based chemotherapy and IMRT, and analyze results according to primary site and nodal status. Methods: Between February 2003, and November 2005, 87 patients with locally advanced SCCHN underwent concurrent IMRT and platinum based chemotherapy. A total of 62 patients were treated with Cisplatin 100 mg/m2 d1,21,43, while 19 were treated with paclitaxel and carboplatin weekly for 7 weeks. Five patients were treated with other platinum based regimens. Follow up was documented in all cases with a median of 520 days (range 107 - 1269 days). Results: Patients were distributed among primary sites as follows: Hypopharynx (HP) 7 (8.0%), Larynx (L) 11(12.4%), Nasopharynx (NP) 13 (14.6%), and Oropharynx (OP) 56 (63.0%). T stage distribution was: T1: 16 patients (18.0%); lesions more advanced than T1 (>T1): 68 (76.4%). N stage distribution was, N0 :16 patients (18.0%), N1: 8 (9.0 %),nodal stage N2a or higher: 61 (68.5%). Median age was 57 years (range 32–75), and 63 patients (71.0%) were male. The median overall survival (OS) and disease-free survival (DFS) post-therapy was not reached. The 3 year OS rate for the entire cohort was 86% (L 82%, NP 89 %, OP 86 % HP 80%). The 3 year DFS rate for the entire cohort was 74%, (L 85%, NP 60%, and OP 75%, HP 76%). There was no correlation between OS and T or N stage (p=0.143 and 0.44 respectively), or between DFS and T-stage (p=0.4). A significant correlation was found between DFS and N stage (p=0.008). Conclusion: With moderate follow up, this retrospective analysis reveals an excellent outcome for patients with locally advanced SCCHN treated with chemotherapy and IMRT concurrently, supporting concurrent therapy as the current standard of care. The significant correlation of DFS and nodal status suggests a possible greater impact future approaches such as induction therapy may have on patients with advanced nodal disease.

No significant financial relationships to disclose.

Chronic exposure to typical or atypical antipsychotics in rodents: temporal effects on central alpha7 nicotinic acetylcholine receptors

A decrease in alpha7 nicotinic acetylcholine receptors in the hippocampus has been hypothesized to contribute to alterations in auditory gating and other behavioral impairments in schizophrenia. However, while both typical and atypical neuroleptics are routinely used in the therapeutics of schizophrenia, little is known about their effects on auditory gating or alpha7 nicotinic acetylcholine receptor expression particularly when they are administered for extended periods of time (which is common in the clinical setting). In the present study in normal rats, the residual effects of prior chronic treatment (90 or 180 days) with representative typical and atypical neuroleptics (oral haloperidol, 2.0 mg/kg/day; chlorpromazine, 10.0 mg/kg/day, risperidone, 2.5 mg/kg/day; or olanzapine, 10.0 mg/kg/day) on prepulse inhibition of the auditory gating response were investigated. The densities of alpha7 nicotinic acetylcholine receptors were subsequently measured using [125I]-alpha-bungarotoxin autoradiography. The results indicated that none of the compounds significantly altered the startle amplitude or prepulse inhibition response either during drug treatment (day 60) or after 90 or 180 days of treatment (i.e. during a drug free washout). However, prior exposure to chlorpromazine, risperidone and olanzapine for 90 days resulted in modest but significant (P<0.01) decreases in [125I]-alpha-bungarotoxin binding sites in some brain regions (e.g. posterior cortical amygdala). After 180 days of treatment, decreases in [(125I]-alpha-bungarotoxin binding ranging from approximately 12% (lateral dentate gyrus) up to 24% (e.g. CA1 hippocampal region) were evident in the risperidone group in 13 of the 36 regions analyzed while decreases associated with the other neuroleptics agents were still present, but not statistically significant. These data indicate that the commonly used atypical neuroleptic, risperidone is associated with time dependent and persistent negative effects on an important biological substrate of memory (i.e. the alpha7 nicotinic receptor), but that the magnitude of the deficits was not sufficient to impair auditory gating.

Comparison of Galantamine and Donepezil for Effects on Nerve Growth Factor, Cholinergic Markers, and Memory Performance in Aged Rats

This study was designed to determine 1) whether repeated exposures to the acetylcholinesterase inhibitors (AChEIs) galantamine (GAL) or donepezil (DON) resulted in positive effects on nerve growth factor (NGF) and its receptors, cholinergic proteins, and cognitive function in the aged rat, and 2) whether GAL had any advantages over DON given its allosteric potentiating ligand (APL) activity at nicotinic acetylcholine receptors. Behavioral tests (i.e., water maze and light/dark box) were conducted in aged Fisher 344 rats during 15 days of repeated (subcutaneous) exposure to either GAL (3.0 or 6.0 mg/kg/day) or DON (0.375 or 0.75 mg/kg/day). Forty-eight hours after the last drug injection, cholinergic receptors were measured by [(125)I]-(+/-)-exo-2-(2-iodo-5-pyridyl)-7-azabicyclo[2.2.1]heptane ([(125)I]IPH; epibatidine analog), (125)I-alpha-bungarotoxin ((125)I-BTX), [(3)H]pirenzepine ([(3)H]PRZ), and [(3)H]-5,11-dihydro-11-[((2-(2-((dipropylamino)methyl)-1-piperidinyl)ethyl)amino)carbonyl]-6H-pyrido(2,3-b)(1,4)-benzodiazepin-6-one methanesulfonate ([(3)H]AFDX-384, or [(3)H]AFX) autoradiography. Immunochemical methods were used to measure NGF, high (TrkA and phospho-TrkA)- and low (p75 neurotrophin receptor)-affinity NGF receptors, choline acetyltransferase (ChAT), and the vesicular acetylcholine transporter (VAChT) in memory-related brain regions. Depending on dose, both GAL and DON enhanced spatial learning (without affecting anxiety levels) and increased [(125)I]IPH, [(3)H]PRZ, and [(3)H]AFX (but decreased (125)I-BTX) binding in some cortical and hippocampal brain regions. Neither AChEI was associated with marked changes in NGF, NGF receptors, or VAChT, although DON did moderately increase ChAT in the basal forebrain and hippocampus. The results suggest that repeated exposures to either GAL or DON results in positive (and sustained) behavioral and cholinergic effects in the aged mammalian brain but that the APL activity of GAL may not afford any advantage over acetylcholinesterase inhibition alone.

Dose verification for patients undergoing IMRT

At Emory Clinic intensity-modulated radiation therapy (IMRT) was started by using dynamic multileaf collimators (dMLC) as electronic tissue compensators in August 1998. Our IMRT program evolved with the inclusion of a commercially available inverse treatment planning system in September 1999. While the introduction of electronic tissue compensators into clinical use did not affect the customary radiation oncology practice, inverse treatment planning does alter our basic routines. Basic concepts of radiation therapy port designs for inverse treatment planning are different from conventional or 3D conformal treatments. With inverse treatment planning, clinicians are required to outline a gross tumor volume (GTV), a clinical target volume (CTV), critical normal structures, and to design a planning target volume (PTV). Clinicians do not designate the volume to be shielded. Because each IMRT radiation portal is composed of many beamlets with varying intensities, methods and practice used to verify delivered dose from IMRT portals are also different from conventional treatment portals. Often, the validity of measured data is in doubt. Therefore, checking treatment planning computer output with measurements are confusing and fruitless, at times. Commissioning an IMRT program and routine patient dose verification of IMRT require films and ionization chamber measurements in phantom. Additional specialized physics instrumentation is not required other than those available in a typical radiation oncology facility. At this time, we consider that routine quality assurance prior to patient treatments is necessary.

Benign parotid hypertrophy on +HIV patients: limited late failures after external radiation

PURPOSE

Although 8-10 Gy of external radiation therapy for +HIV associated parotid hypertrophy has achieved high response rates, the responses were transient with only 1/12 of patients retaining cosmetic control at median follow-up procedures of 9.5 months. Retreatment for failures after 8-10 Gy has also been unsatisfactory. Having shown that 24 Gy of external radiation therapy for benign parotid hypertrophy produced more durable cosmetic control than 8-10 Gy, we now report on longer follow-up periods on a group of patients receiving 24 Gy.

MATERIALS AND METHODS

Twenty +HIV patients with clinical and radiographic evidence of lymphoepithelial lesions of the parotid were treated with 24 Gy of external radiation therapy using daily 1.5 Gy fractions; parallel opposed technique and 6 MV photons were used in 19 patients, and unilateral electron treatment was performed for one patient.

RESULTS

With a mean follow-up period of 24 months, the cosmetic control appears durable. We have had no late failures past 24 months. Two patients have complained of modest xerostomia. There was no correlation with size of the cyst and eventual cosmetic result.

CONCLUSIONS

Twenty-four Gy produces durable parotid control for HIV associated lymphoepithelial lesions of the parotid glands in +HIV patients. Failures after 2 years are uncommon and the side effects have been tolerable.

'Loop' domain deletional mutant of Bcl-xL is as effective as p29Bcl-xL in inhibiting radiation-induced cytosolic accumulation of cytochrome c (cyt c), caspase-3 activity, and apoptosis

PURPOSE/OBJECTIVE

To investigate the effect of the enforced expression of p29Bcl-xL or its loop deletional mutant, p18Bcl-xLdelta, on irradiation-induced apoptosis and cell-cycle distribution of HL-60 cells.

MATERIALS & METHODS

We compared the irradiation-induced molecular cascade of apoptosis in control human AML HL-60/neo versus Bcl-xL overexpressing (approximately 8-fold) (HL-60/Bcl-xL) and HL-60/Bcl-XLdelta cells that express the loop domain deletional mutant construct (delta26-83 AA) of Bcl-xL. The three cell lines were irradiated with 6MV photons to varying doses up to 20 Gy. Following this, cytosolic cyt c levels, caspase-3 activity, and the Bcl-2 family of proteins were evaluated utilizing Western blot analysis (whole cell lysate or cytosolic S-100 fraction). Apoptosis was assessed by internucleosomal DNA fragmentation, Annexin-V staining and FACS analysis, as well as by morphologic criteria. The cell-cycle effects of radiation were analyzed by flow cytometry.

RESULTS

Eight hours following irradiation (12 Gy) of HL-60/neo cells, a marked increase (approximately 8-fold) in the cytosolic accumulation of cyt c in the S-100 fraction was observed. This was associated with the cleavage of caspase-3, as well as the generation of its poly (ADP-ribose) polymerase (PARP) and DFF (DNA fragmentation factor)-45 cleavage activity. Twenty-four to forty-eight hours after irradiation, internucleosomal DNA fragmentation and positive Annexin-V staining (32.3+/-3.3%) was detected in HL-60/neo cells. In contrast, in both HL-60/Bcl-xL and HL-60/Bcl-xLdelta cells, a significantly lower percentage of apoptotic cells (p<0.05) were detected and internucleosomal DNA fragmentation was not induced. Following irradiation, Western analysis neither demonstrated any significant alteration in Bcl-2, p29Bcl-xL, p18Bcl-xLdelta, or Bax; nor induced CD95 (Fas receptor) or Fas ligand expression in any cell type. However, in all cell types, irradiation produced approximately a 2-fold increase in the percentage of cells in the G2/M phase of the cell cycle.

CONCLUSION

These results demonstrate that an intact loop domain is not necessary for the full antiapoptotic function of Bcl-xL against irradiation-induced cytosolic accumulation of cyt c, caspase activation, and apoptosis of HL-60 cells. Additionally, the cell-cycle effects of ionizing radiation in HL-60 cells are not affected by enforced expression of Bcl-xL or Bcl-xLdelta.

Anatomic variation of extrahepatic biliary tree structures: importance in treatment planning for radiation therapy

PURPOSE

To demonstrate the variable location of biliary tree components and to assess two treatment planning rules of thumb used for locating porta hepatic nodes for radiation therapy.

MATERIALS AND METHODS

The distance of the common hepatic duct bifurcation and duodenal papilla from adjacent vertebral bodies was measured on 34 cholangiograms, and their relationships to particular vertebral body levels were recorded. Adequacy of treatment volume to encompass porta hepatic lymph nodes was evaluated in 30 of these cholangiograms by constructing radiation portals according to the two rules of thumb.

RESULTS

Location of the common hepatic duct bifurcation and duodenal papilla varied widely. The treatment portal encompassed 13% (four of 30) of cases when the first rule of thumb was used and 80% (24 of 30) of cases when the second rule of thumb was used.

CONCLUSION

The wide variability of location of extrahepatic biliary tree structures suggests the need for individualized treatment planning so that sensitive and dose-limiting healthy tissues can be optimally excluded from radiation treatment portals. Computed tomography and other imaging modalities enable precise location of biliary tree components for radiation treatment planning.

A totally integrated simulation technique for three-field breast treatment using a CT simulator

A method was devised to simulate patients with breast cancer in the actual treatment position utilizing a diagnostic CT spiral scanner, 3-D Image Workstation for virtual simulation, and a laser coordinate system to transfer planning parameters to the patient's skin. It was desired to produce non-divergent tangential beams through the lung as well as a matched line for tangential and supraclavicular fields. The patients were immobilized in an Alpha CradleTM cast. Radio-opaque markers were placed on the superior, inferior, medial, and lateral margins of the field so as to afford appropriate initial field set-up approximations. The patient was scanned. The data set was then transferred to the workstation where an isocenter was chosen. The patient was marked. Virtual simulation was then performed. This method employed a half beam technique for the posterior edge of the tangential fields. Table rotation and blocking of the superior margin of the tangential fields were used to produce a vertical edge to match a supraclavicular field. Using a beam's eye view the lateral tangent was matched to the medial exit. A digitally reconstructed radiograph was created to define the tangent fields and place the supraclavicular block. Our initial experience with 50 patients verifies that this is a reproducible and accurate technique. Time required for immobilization and tangential field simulation is approximately 30 minutes. Data is available for 3-D treatment planning or 2-D treatment planning on a reconstructed transverse slice angled to match the collimator angle through the patient. Using a CT simulator for simulation of breast cancer affords accuracy of at least equal magnitude to conventional simulators as determined by beam films and ease of set-up. This technique also affords greater ease in changing treatment parameters without having to resimulate the patient.

Conservative treatment of early-stage breast cancer in a medically indigent population

The compliance with a program of breast-conservation treatment for early-stage breast cancer and the results of that treatment among women treated between January 1983 and January 1992 was investigated in a large inner-city public hospital serving a primarily black population. Medical records and charts were reviewed for 25 consecutive patients with stage I and II breast cancer seen in consultation in the radiation oncology department. Of those 25 patients, 20 underwent lumpectomy and radiation therapy. Survival, disease-free survival, and local recurrence-free survival were computed using the Kaplan-Meier method. Compliance was evaluated based on time to complete the prescribed course of radiotherapy after a lumpectomy. Five-year local recurrence-free survival for stage I and II patients was 95% (confidence interval [CI]: 71% to 99%). Five-year overall survival for stage II patients was 71% (CI: 31% to 92%), and disease-free survival was 74% (CI: 36% to 91%). This study demonstrates that a program of breast-conservation treatment for early-stage breast cancer can be implemented with good results, excellent treatment compliance, and 100% follow-up in a population of medically indigent women.

Definitive radiation therapy for extrahepatic bile duct carcinoma

PURPOSE

To evaluate retrospectively the role of radiation therapy for extrahepatic bile duct (EHBD) carcinoma.

MATERIALS AND METHODS

Twenty-seven patients with local-regional EHBD carcinomas were treated with definitive radiation therapy. Radiation therapy was delivered by means of external beam radiation therapy (EBRT) alone or combined with transcatheter iridium-192 brachytherapy. The median total dose was 54 Gy (range, 30-144 Gy). Survival rates were calculated and compared by using the log-rank test. Possible prognostic factors affecting survival were evaluated by means of univariate analysis.

RESULTS

The median survival of all patients was 13 months, with 1- and 2-year actuarial survival rates of 52% and 10%, respectively. Univariate analysis revealed that men, patients with tumors limited to the bile duct, and patients receiving EBRT doses of at least 45 Gy had significantly better outcomes. Local-regional recurrence was the main cause of treatment failure (82%). Two patients developed gastric outlet obstruction.

CONCLUSION

Patients with locally advanced EHBD carcinomas have a low survival rate. Certain factors, however, appear to have prognostic significance.

Fast-neutron therapy in advanced head and neck cancer: a collaborative international randomized trial

PURPOSE

To compare the efficacy of fast-neutron radiotherapy with that of conventionally fractionated photon therapy in the management of patients with locally advanced squamous cell carcinoma of the head and neck.

METHODS AND MATERIALS

Patients with Stage III or IV disease were randomized to receive either 20.4 Gy/12 fractions/4 weeks of neutrons or 70 Gy/35 fractions/7 weeks of photons (control). Between April 1986 and March 1991, 178 patients were entered, 169 of whom were eligible for analysis. The treatment arms were balanced for age, stage, and performance status, but not for primary site of origin.

RESULTS

Complete response occurred in 70 and 52% with neutrons and photons, respectively (p = 0.006). Local regional failure at 3 years for all patients was 63% for neutrons and 68% for photons. Actuarial overall survival curves were virtually identical in both study arms, falling to 27% at 3 years. Acute toxicity was similar in the two arms, but late grade 3-5 toxicity was 40% with neutrons compared to 18% with photons (p = 0.008).

CONCLUSION

Although the initial response rate was higher with neutrons, permanent local control and survival were not improved, and the incidence of late normal tissue toxicity was increased. As a result, fast-neutron therapy for advanced squamous cell carcinoma of the head and neck can only be recommended for patients in whom the logistic benefit of treatment in 12 sessions over 4 weeks outweighs the increased risk of late toxicity.

Low-dose radiotherapy for multicystic benign lymphoepithelial lesions of the parotid gland in HIV-positive patients: long-term results

BACKGROUND

Multicystic benign lymphoepithelial lesions of the parotid gland (BLL) seen in patients with human immunodeficiency virus (HIV) can produce considerable cosmetic deformity as well as physical discomfort. We previously reported our preliminary results with low-dose radiotherapy in this disease, and all 8 patients were satisfied with the initial improvement in their appearance. We now report the long-term follow-up of those patients and additional patients.

METHODS

Twelve HIV-positive patients with BLL were treated with 8-10 Gy of external radiation using 2-Gy daily fractions. Objective responses and subjective duration of patient-defined cosmetic control were recorded.

RESULTS

All 12 patients (100%) had at least a 50% decrease in the size of their parotid masses. Five of 12 (42%) had a complete response and 7 (58%) had a partial response. Persisting complete response was achieved in only 1 patient, however, with relapse in the other 11 patients. Cosmetic palliation, as judged by the patients, was achieved for a median of 9.5 months. Eight patients were subsequently retreated with doses of 6-16 Gy (median and mode: 10 Gy). None (0%) of the 8 patients retreated achieved local control.

CONCLUSIONS

Very low-dose radiation (8-10 Gy) provides reliable but temporary cosmetic palliation for BLL. Retreatment was unsatisfactory, and we are now investigating higher initial doses of radiation to prolong palliation and eliminate recurrences.

Photon versus fast neutron external beam radiotherapy in the treatment of locally advanced prostate cancer: results of a randomized prospective trial

PURPOSE

To evaluate the effectiveness of fast neutron radiation therapy in treatment of locally advanced carcinomas of the prostate.

METHODS AND MATERIALS

From April 1986 to October 1990, 178 patients were entered on a prospective, multi-institutional randomized study of the NCI-sponsored Neutron Therapy Collaborative Working Group. This trial compared external beam photon irradiation (7000-7020 cGy) with external beam neutron irradiation (2040 ncGy) for patients with high-grade T2 or T3-4, N0-1, M0 adenocarcinomas of the prostate. Eighty-nine patients were randomized to each treatment. Six patients were subsequently judged to be ineligible, leaving 85 photon and 87 neutron randomized patients eligible for analysis.

RESULTS

With a follow-up time ranging from 40 to 86 months (68 months median follow-up) the 5-year actuarial clinical local-regional failure rate for patients treated with neutrons was 11%, vs. 32% for photons (p < 0.01). Incorporating the results of routine posttreatment prostate biopsies, the resulting "histological" local-regional tumor failure rates were 13% for neutrons vs. 32% for photons (p = 0.01). To date, actuarial survival and cause-specific survival rates are statistically indistinguishable for the two patient cohorts, with 32% of the neutron-treated patient deaths and 41% of the photon-treated patient deaths caused by prostate cancer (p = n.s.). Prostate specific antigen (PSA) values were elevated in 17% of neutron-treated patients and 45% of photon-treated patients at 5 years (p < 0.001). Severe late complications of treatment were higher for the neutron-treated patients (11% vs. 3%), and were inversely correlated with the degree of neutron beam shaping available at the participating institutions. Neutron treatment delivery utilizing a fully rotational gantry and multileaf collimator did not result in an increase in severe late effects when compared to photon treatment.

CONCLUSION

High energy fast neutron radiotherapy is safe and effective when adequate beam delivery systems and collimation are available, and it is significantly superior to external beam photon radiotherapy in the local-regional treatment of large prostate tumors.

Neutron vs. photon radiation therapy for inoperable regional non-small cell lung cancer: results of a multicenter randomized trial

PURPOSE

To determine, with a prospective, multicenter randomized study, whether fast neutron radiation therapy improves the outcome for patients with non-small cell lung cancer, as compared to conventional photon radiotherapy.

METHODS AND MATERIALS

From September 1986 to March 1991, a total of 200 patients with inoperable regional non-small cell lung cancer were randomized to 20.4 Gy in 12 fractions with neutrons versus 66 Gy in 33 fractions with photons. Inoperable patients with Radiation Therapy Oncology Group Stages I, II, III, or IV(M0) disease, Karnofsky Performance Score > or = 70, and who had received no previous therapy for their non-small cell lung cancer were eligible for the study. Of the 200 patients randomized, a total of 193 patients, 99 on the neutron arm and 94 on the photon arm, were eligible for analysis. The two treatment groups were balanced with regards to prognostic factors. At the time of this analysis, the median at-risk follow-up was 33 months, with a minimum follow-up of 16 months.

RESULTS

No difference in overall survival was observed; however, there was a statistically significant improvement in survival for patients with squamous cell histology (p = 0.02), and a trend toward improved survival for those with favorable prognostic factors (i.e., patients who were not T4, N3, and had no pleural effusion or weight loss > 5% from baseline) (p = 0.15), favoring the neutron-treated group. With the exception of skin and subcutaneous changes, acute and late toxicity was similar in both arms.

CONCLUSION

In selected patients with inoperable regional non-small cell lung cancer (e.g., squamous cell histology, favorable prognostic factors), fast neutron irradiation provides a therapeutic benefit over conventional photon radiotherapy.

Neutron versus photon irradiation for unresectable salivary gland tumors: final report of an RTOG-MRC randomized clinical trial. Radiation Therapy Oncology Group. Medical Research Council

PURPOSE

To compare the efficacy of fast neutron radiotherapy versus conventional photon and/or electron radiotherapy for unresectable, malignant salivary gland tumors a randomized clinical trial comparing was sponsored by the Radiation Therapy Oncology Group in the United States and the Medical Research Council in Great Britain.

METHODS AND MATERIALS

Eligibility criteria included either inoperable primary or recurrent major or minor salivary gland tumors. Patients were stratified by surgical status (primary vs. recurrent), tumor size (less than or greater than 5 cm), and histology (squamous or malignant mixed versus other). After a total of 32 patients were entered onto this study, it appeared that the group receiving fast neutron radiotherapy had a significantly improved local/regional control rate and also a borderline improvement in survival and the study was stopped earlier than planned for ethical reasons. Twenty-five patients were study-eligible and analyzable.

RESULTS

Ten-year follow-up data for this study is presented. On an actuarial basis, there continues to be a statistically-significant p = 0.009) but there is no improvement in overall survival (15% vs. 25%, p = n.s.). Patterns of failure are analyzed and it is shown that distant metastases account for the majority of failures on the neutron arm and local/regional failures account for the majority of failures on the photon arm. Long-term, treatment-related morbidity is analyzed and while the incidence of morbidity graded "severe" was greater on the neutron arm, there was no significant difference in "life-threatening" complications. This work is placed in the context of other series of malignant salivary gland tumors treated with definitive radiotherapy.

CONCLUSIONS

Fast neutron radiotherapy appears to be the treatment-of-choice for patients with inoperable primary of recurrent malignant salivary gland tumors.

Fast neutron radiotherapy for locally advanced prostate cancer. Final report of Radiation Therapy Oncology Group randomized clinical trial

Between June 1977 and April 1983 the Radiation Therapy Oncology Group (RTOG) sponsored a Phase III randomized trial investigating the use of fast neutron radiotherapy for patients with locally advanced (Stages C and D1) adenocarcinoma of the prostate gland. Patients were randomized to receive either conventional photon radiation or fast neutron radiation used in a mixed-beam (neutron/photon) treatment schedule. A total of 91 analyzable patients were entered into the study, and the two patient groups were balanced with respect to the major prognostic variables. Actuarial curves are presented for local/regional control and "overall" survival. Ten-year results for clinically assessed local control are 70% for the mixed-beam group versus 58% for the photon group (p = 0.03) and for survival are 46% for the mixed-beam group versus 29% for the photon group (p = 0.04). This study suggests that a regional method of treatment can influence both local tumor control and survival in patients with locally advanced adenocarcinoma of the prostate gland.

Improved survival duration in patients with unresected solitary brain metastasis using accelerated hyperfractionated radiation therapy at total doses of 54.4 gray and greater. Results of Radiation Therapy Oncology Group 85-28

BACKGROUND

Although there have been occasional reports of improved response with greater doses of irradiation for unresected brain metastases, dose escalation has not been systematically studied in a cohort of patients with solitary brain metastasis. The current study examines this group of patients to evaluate dose escalation using accelerated hyperfractionated radiation therapy (XRT) with regard to survival, patterns of failure, and toxicity.

METHOD

Radiation Therapy Oncology Group (RTOG) 85-28, a Phase I/II randomized trial of accelerated hyperfractionated XRT for patients with unresected supratentorial brain metastases, enrolled 153 patients with solitary brain metastasis. Whole brain dose was 32 Gray (Gy) administered in 1.6 Gy fractions twice a day with an interfraction interval of 4-8 hours. Boost dose was escalated to total doses of 48.0, 54.4, 64.0, and 70.4 Gy.

RESULTS

Acute and late toxicities were acceptable. The median survival time and 1-year survival rates were 4.9 months and 20% at 48 Gy; 5.4 months and 33% at 54.4 Gy; 7.2 months and 28% at 64 Gy; and 8.2 months and 37% at 70.4 Gy, respectively. Comparison of the upper three dose treatment arms to the 48 Gy treatment arm revealed a superior survival time with doses of 54.4 Gy and greater (P = 0.05). Improvement in neurologic function appeared to increase with dose escalation, with 25% of patients experiencing improvement at doses of 48 Gy, 38% at 54.4 Gy, 50% at 64 Gy, and 63% at 70.4 Gy (P = not significant).

CONCLUSION

A radiation dose response for survival time appears to exist with the use of accelerated hyperfractionated XRT for patients with unresected solitary brain metastasis.

Logistics in designing clinical trials for etanidazole (SR 2508): an RTOG experience

In a Phase II study of etanidazole (SR 2508), the dose of 17 x 2 g/m2 (total drug dose: 34 g/m2) was tested in 33 patients and the toxicity was deemed acceptable. A Phase III trial is now in progress comparing conventional radiotherapy with conventional radiotherapy plus etandizole (2 g/m2 i.v. 30 to 60 min before radiotherapy each Monday, Wednesday, and Friday to 34 g/m2 in 17 doses) in patients with unresectable head and neck carcinomas. A recent analysis showed only 14.7% grade 1 and 3.9% Grade 2 peripheral neuropathy. In the initial study design, 133 evaluable patients per treatment arm could achieve an 80% level of power of detecting a 15% difference in local-regional control rates between the radiotherapy arm (25% local-regional control at 2 years) and the radiotherapy plus etanidazole arm (assuming a 40% rate). Allowing for 20 ineligible cases in each arm, a total number of 306 was required. An interim analysis showed that 27% of the patients assigned to radiotherapy plus etanidazole are receiving less than 14 doses of the drug. It is assumed that less than 14 drug doses will not produce any therapeutic gain, therefore, a true 40% local-regional control rate in the radiotherapy plus etanidazole arm will be observed as a 36% rate when analyzed by assigned treatment. Using this information, the study was modified to have an 80% level of power in detecting a difference between a 25% local-regional control rate in the radiotherapy group and a 36% rate in the radiotherapy plus etanidazole group. Allowing for a 10% patient ineligibility rate, 518 patients are required. With 12 patients entered per month, it is estimated that patient accrual to this study will continue through October 1991.

The effect of local-regional control on distant metastatic dissemination in carcinoma of the head and neck: results of an analysis from the RTOG head and neck database

A retrospective analysis of the effect of local control on the development of distant metastases was performed in 2648 patients with carcinoma of the head and neck selected from the RTOG database. The 5-year time-adjusted incidence of distant metastases was 21% for patients who were in local-regional control at 6 months after the start of treatment, compared to 38% for local-regional failure patients (p less than 0.001). The incidence of distant metastases detected between the interval of 6 months to 2.5 years after treatment was significantly increased in patients with tumors of the oral cavity, oropharynx, supraglottic larynx, and glottis who developed local-regional failure within this time period, compared to those who remained locally controlled (19% distant metastases for local-regional failure vs 7% for local-regional control (p less than 0.001)). In contrast, there as no difference in the incidence of distant metastases in patients with carcinoma of the nasopharynx or hypopharynx regardless of the local-regional disease status. A Cox proportional hazards regression analysis demonstrated that local-regional control was the most significant variable affecting the development of distant metastases, followed by tumor site, N-stage, and T-stage. For all tumor sites, except for the hypopharynx and nasopharynx, improvements in local-regional control are likely to improve survival. Tumors of the hypopharynx and nasopharynx have a higher probability of micro-metastatic dissemination at the time of initial diagnosis, and until effective methods to treat disseminated disease are developed, the effect of local control on survival will not be readily discerned.

Randomized study of preoperative versus postoperative radiation therapy in advanced head and neck carcinoma: long-term follow-up of RTOG study 73-03

This is a report of a 10-year median follow-up of a randomized, prospective study investigating the optimal sequencing of radiation therapy (RT) in relation to surgery for operable advanced head and neck cancer. In May 1973, the Radiation Therapy Oncology Group (RTOG) began a Phase III study of preoperative radiation therapy (50.0 Gy) versus postoperative radiation therapy (60.0 Gy) for supraglottic larynx and hypopharynx primaries. Of 277 evaluable patients, duration of follow-up is 9-15 years, with 7.6% patients lost to follow-up before 7 years. Loco-regional control was significantly better for 141 postoperative radiation therapy patients than for 136 preoperative radiation therapy patients (p = 0.04), but absolute survival was not affected (p = 0.15). When the analysis was restricted to supraglottic larynx primaries (60 postoperative radiation therapy patients versus 58 preoperative radiation therapy patients), the difference for loco-regional control was highly significant (p = .007), but not for survival (p = 0.18). In considering only supraglottic larynx, 78% of loco-regional failures occurred in the first 2 years. Thirty-one percent (18/58) of preoperative patients failed locally within 2 years versus 18% (11/60) of postoperative patients. After 2 years, distant metastases and second primaries became the predominant failure pattern, especially in postoperative radiation therapy patients. This shift in the late failure pattern along with the increased number of unrelated deaths negated any advantage in absolute survival for postoperative radiation therapy patients. The rates of severe surgical and radiation therapy complications were similar between the two arms. Because of an increased incidence of late distant metastases and secondary primaries, additional therapeutic intervention is required beyond surgery and postoperative irradiation to impact significantly upon survival.

Elapsed treatment days--a critical item for radiotherapy quality control review in head and neck trials: RTOG report

For all randomized trials since 1978, the Radiation Therapy Oncology Group has required the study chairman for radiation therapy to review the treatment given to each patient. The chairman scores the compliance of the treatment borders, total dose, fraction, and total elapsed time relative to the protocol prescription at the primary site, regional nodes, and any critical structure. The individual parameters are then considered together to derive an "overall" treatment score. For two RTOG head and neck studies in patients with moderately and very advanced carcinomas, the "overall" treatment was classified as unacceptable if the treatment at primary was scored unacceptable with respect to dose, fractionation, and field borders. However, prolonged elapsed treatment was not included. Analysis of these studies with 426 evaluable patients was performed to assess the relationship of unacceptable "overall" treatment compliance with outcome. Patients with prolonged treatment elapsed days (14 days beyond the protocol prescription) exhibited significantly poorer loco-regional control (13% vs. 27% at 3 years with p = .007) and absolute survival (13% vs. 26% at 3 years with p = .01). As a result, the criteria for unacceptable "overall" treatment were revised to include prolonged elapsed treatment days. Further multivariate analyses showed the revised criteria identified patients with significantly poorer loco-regional control and absolute survival even after adjusting for other prognostic factors.

High energy (42-66 MeV reactions) fast neutron dose optimization studies in the head and neck, thorax, upper abdomen, pelvis and extremities

Five hundred and fifty patients were entered into a set of dose-searching studies designed to determine normal tissue tolerance to high energy (42-66 MeV reactions) fast neutrons delivered in 12 equal fractions over 4 weeks. Participating institutions included: The Fermilab (66 MeV p+----Be), The University of Washington (50 MeVp+----Be), U.C.L.A. (45 MeVH-----Be), M.D. Anderson Hospital (42 MeVH-----Be), and The Cleveland Clinic (42 MeVp+----Be). Patients were stratified by treatment facility and then randomized to receive 16, 18 or 20 Gy for tumors located in the upper abdomen or pelvis, and 18, 20 or 22 Gy for tumors located in the head and neck, thorax or extremities. Following completion of the randomized protocols, additional patients were studied at the 20.4 Gy level in the head and neck, thorax and pelvis. Normal tissue effect scoring was accomplished using the RTOG-EORTC acute and late normal tissue effect scales. Acute Grade 3 + toxicity rates in the head and neck were 19% for 20/20.4 Gy and 20% for 22 Gy. Time adjusted late toxicity rates in the head and neck at 12 months were 15% for 20/20.4 Gy and 0% for 22 Gy. The 18 Gy treatment arm of the head and neck protocol was dropped early in the study after only two patients were accrued. For cases treated in the thorax, acute Grade 3 + toxicity rates were 6% for 18 Gy, 15% for 20/20.4 Gy and 7% for 22 Gy. Late toxicity rates at 12 months were 0% for 18 Gy, 11% for 20/20.4 Gy and 18% for 22 Gy. Acute Grade 3+ toxicity rates in the upper abdomen were 0% for 16 Gy, 8% for 18 Gy and 12% for 20 Gy. There were no Grade 3 + late toxicities in the upper abdomen. In the pelvis, acute Grade 3 + toxicity rates were 0% for 16 Gy, 3% for 18 Gy and 3% for 20/20.4 Gy. Late Grade 3 + toxicities at 24 months were 20% for 16 Gy, 5% for 18 Gy and 24% for 20/20.4 Gy. In extremities, acute Grade 3 + toxicity rates were 7% for 20 Gy and 21% for 22 Gy while at 12 months, late Grade 3 + toxicity rates were 14 and 35%, respectively. The 18 Gy treatment arm of the extremities protocol was dropped early in the study after only two patients were accrued. Factors associated with normal tissue effects in addition to treatment dose are discussed.

Transient and chronic neurological complications of fast neutron radiation for adenocarcinoma of the prostate

The records of 132 patients participating in clinical trials using fast neutron (n = 94), mixed neutron and photon (n = 16), or conventional photon (n = 22) irradiation for primary management of prostatic cancer were retrospectively reviewed to assess treatment-related neurological complications. With a median follow-up of 14 months (range 1 to 101 months), 31/132 patients (26 neutron, 3 mixed beam, 2 photon) have experienced either sciatica beginning during or shortly after treatment, or diminished bladder or bowel continence that developed at a median time of 6.5 months following treatment. Sciatica responded to oral steroids and was usually self-limited, whereas sphincter dysfunction appears to be permanent. Pre-treatment risk factors for complications included a history of hypertension, diabetes, cigarette smoking or peripheral vascular disease, with 81% of affected patients having one or more risk factors compared with 55% of unaffected patients (p = 0.01). Seven patients have moderate (5) or severe (2) residual problems, all in the cohorts receiving neutrons (6/7) or mixed beam therapy (1/7).

A technique for treating local breast cancer using a single set-up point and asymmetric collimation

Using both pairs of asymmetric jaws of a linear accelerator local-regional breast cancer may be treated from a single set-up point. This point is placed at the abutment of the supraclavicular fields with the medial and lateral tangential fields. Positioning the jaws to create a half-beam superiorly permits treatment of the supraclavicular field. Positioning both jaws asymmetrically at midline to define a single beam in the inferoanterior quadrant permits treatment of the breast from medial and lateral tangents. The highest possible matching accuracy between the supraclavicular and tangential fields is inherently provided by this technique. For treatment of all fields at 100 cm source to axis distance (SAD) the lateral placement and depth of the set-up point may be determined by simulation and simple trigonometry. We elaborate on the clinical procedure. For the technologists treatment of all fields from a single set-up point is simple and efficient. Since the tissue at the superior border of the tangential fields is generally firmer than in mid-breast, greater accuracy in day-to-day set-up is permitted. This technique eliminates the need for table angles even when tangential fields only are planned. Because of half-beam collimation the limit to the tangential field length is 20 cm. Means will be suggested to overcome this limitation in the few cases where it occurs. Another modification is suggested for linear accelerators with only one independent pair of jaws.

The role of hemoglobin concentration in the outcome of misonidazole-sensitized radiotherapy of head and neck cancers: based on RTOG trial #79-15

Recent data from the DAHANCA (Danish Head and Neck Cancer) 2 study implies a positive effect of high hemoglobin concentration in concert with misonidazole for the treatment of head and neck cancers by radiotherapy. We have therefore reviewed and updated our analysis of RTOG protocol 79-15, which included the effect of misonidazole plus radiotherapy in a presumably similar population. Despite additional follow-up and more sophisticated analysis, our analysis does not demonstrate an influence of hemoglobin concentration on any of the outcome measures we examined. Possible explanations for the difference in findings of RTOG 79-15 and DAHANCA 2 are discussed. Radiation therapy of head and neck squamous cancers, Hypoxia and hemoglobin conc. in head and neck cancers, Oral cavity cancer, Effect of radiation therapy, Oropharynx cancer, Hemoglobin and radiotherapy, Hemoglobin concentration, Effect upon radiotherapy, Irradiation of oropharynx cancer, Hgb effect.

Mixed neutron/photon irradiation of unresectable squamous cell carcinomas of the head and neck: the final report of a randomized cooperative trial

Three hundred and twenty-seven patients with inoperable squamous cell carcinomas of the head and neck were entered on a randomized study comparing a mixture of neutron and photon ("mixed beam") radiation therapy with photon/electron radiation therapy. Neutron treatment was delivered with fixed-beam, physics-laboratory-based equipment. Patients with histologically proven tumors of T-stage T2, T3, or T4 and any N-stage were eligible for randomization. Primary tumor sites were limited to cancers originating in the oral cavity, oropharynx, supraglottic larynx, or hypopharynx. Patients entered on this study now have a minimum at-risk follow-up period of 6 years. Study results reveal no significant differences in overall loco-regional tumor control rates or survival. Subgroup analysis reveals significant differences based on whether or not patients presented with positive lymph nodes. Loco-regional tumor control rates for patients presenting with positive lymph nodes were 30% for mixed-beam-treated patients versus 18% for photon-treated patients (p = 0.05). Loco-regional tumor control rates for patients presenting without positive lymph nodes were 64% for photon-treated patients and 33% for mixed-beam-treated patients (p = 0.004). Control of tumor located in the nodal sites favored mixed beam over photons by a margin of 45% (49/109) to 26% (23/87) with a significance of p = 0.004. Possible explanations for these contradictory findings are discussed.

Impact of initial quality control review on study outcome in lung and head/neck cancer studies--review of the Radiation Therapy Oncology Group experience

The Radiation Therapy Oncology Group (RTOG) initiated cooperative clinical trials in 1971. In 1978, RTOG developed a formalized program of Quality Control (QC) divided into initial and final phases. The initial review process consisted of two steps. The first phase of review is an evaluation performed by a radiation oncologist to verify treatment plan and field borders. The second portion of the initial review process originally consisted of dosimetry calculation verification based on machine data provided by the regional Radiological Physics Center and treatment planning data provided by the accessioning institution. Between 1978 and December 31, 1987, a total of 11,343 cases in 96 RTOG protocols, excluding particle studies, underwent initial review. Of this number, 2227 patients were entered in lung cancer studies and 1341 patients were entered in head/neck cancer studies. Initial review was carried out in 2089 (93.8%) of the lung cancer cases. Missing or delayed data accounted for 138 (6.2%) cases not reviewed initially. In head/neck cancer trials, 1251 (93.2%) received initial review and 90 (6.8%) did not. Our findings suggest that there are sharply defined but long lasting learning experiences involved in clinical trial participation. Consideration may be given to modifying the initial review process to use random sampling of cases accessioned by experienced investigators in ongoing clinical trials and to continuing the total case evaluation on all new studies and cases entered by inexperienced investigators or investigators/institutions with unsatisfactory performance. Recommendations regarding initial review of other sites will await evaluation of the impact of initial review on those sites.

Second malignancies in patients who have head and neck cancer: incidence, effect on survival and implications based on the RTOG experience

The development of second malignant tumors (SMTs), in patients who have had their first tumor treated successfully, represents a serious limitation of current therapeutic strategies for head and neck cancers. To improve our understanding of the current magnitude of the problem and the various factors that might influence its importance, we reviewed the Radiation Therapy Oncology Group's (RTOG) prospectively collected registry of all head and neck patients seen in participating member institutions between February 1977 and April 1980. A total of 928 patients were identified who had squamous cell carcinomas of the head and neck region, no prior or coincident history of another malignant tumor, and whose planned treatment consisted of radiation therapy only. A total of 110 second, independent, malignant tumors occurred in these patients. Overall, the estimated risk of developing a second tumor within 3 years of radiotherapy was 10%, within 5 years 15%, and within 8 years 23%. Minor differences in frequency were observed for different primary sites. These SMTs unquestionably influenced subsequent survival adversely. Analysis of the database also revealed that the extent of the primary tumor influenced the risk of a second; most occurred in patients who presented with the smallest primary tumors because of their better survival. Our data indicate that preventive medicine should have its greatest impact in those patients who are treated for an early stage primary tumor.

Fast neutron radiotherapy for the treatment of carcinoma of the urinary bladder. A review of clinical trials

The major clinical investigation employing fast neutrons in the treatment of invasive bladder cancer are reviewed. Although data suggest that preoperative radiation schedules employing neutrons may result in a greater degree of pathologic downstaging than conventional precystectomy photon regimens, this has not led to an improved survival rate for neutron-treated patients over photon-treated patients. Randomized clinical trials comparing primary neutron irradiation and primary photon irradiation do not disclose an advantage for neutrons over photons as measured by survival rate or freedom from local tumor recurrence. The late complications in normal pelvic tissues following neutron irradiation with low-energy beams exceed those experienced after photon irradiation and have led to an unexpectedly high rate of treatment-related morbidity and mortality. A partial explanation for the toxicity may be attributed to the use of neutron beams with poor depth dose characteristics for the treatment of what is a deep-seated malignancy. An additional explanation is the documented lack of a differential in radioresponsiveness to neutrons between the bladder primary tumor and adjacent normal pelvic tissues.

Fast neutron radiotherapy for sarcomas of soft tissue, bone, and cartilage

The basic radiobiological rationale for the use of fast neutron radiotherapy in the treatment of classically radioresistant tumors such as soft tissue sarcomas, osteogenic sarcomas, and chondrosarcomas is reviewed. There are no definitive randomized studies comparing high and low linear energy transfer radiotherapy for these tumor systems, but a review of published series is highly suggestive of a therapeutic advantage for fast neutrons. For soft tissue sarcomas, the local control rate is 53% (158 of 297) with fast neutrons, compared with 38% (49 of 128) with photons/electrons; for osteogenic sarcomas, the local control rate is 55% (40 of 73) with fast neutrons, compared with 21% (15 of 73) with photons/electrons; and for chondrosarcomas, the local control rate is 49% (25 of 51) with fast neutrons, compared with 33% (10 of 30) with photons/electrons. An ongoing clinical trial for these tumors is also described.

Fast neutron radiotherapy in the treatment of locally advanced adenocarcinoma of the prostate. Clinical experience and future directions

The major clinical experiences using fast neutrons for the treatment of locally advanced prostatic carcinomas are reviewed. In all trials to date, there is evidence that treatment regimens employing a component of fast neutrons achieve results that equal or surpass those obtainable with conventional megavoltage external beam irradiation for comparable groups of patients. Late complications of neutron treatment have not exceeded the complication rate expected by photon irradiation. The structure of the current Radiation Therapy Oncology Group phase III randomized trial comparing neutron and photon treatment of patients with stages B2, C, and D1 disease is discussed.

Neutron radiation therapy for unresectable non-small-cell carcinoma of the lung. A review

Over 200 patients have been entered in five studies investigating the use of fast neutron radiation therapy in the treatment of non-small-cell carcinomas of the lung since 1983. The results of these studies have been inconsistent. Most studies did not show survival rates or local control advantages over standard photon radiation therapy. Side effects from studies employing mixed photon-neutron treatment plans or clinically oriented, high-energy cyclotrons were seen to be comparable to those of standard courses of radiation therapy, representing a considerable improvement over those studies utilizing low-energy cyclotrons for a full course of radiation therapy, which resulted in unacceptably high complication rates. A new phase III study utilizing high-energy isocentric neutron beams has been designed and implemented, and over 100 patients have been entered to date. The current status of fast neutron radiation therapy in the treatment of non-small-cell lung cancer is reviewed.

Evaluation of neutron irradiation of pancreatic cancer. Results of a randomized Radiation Therapy Oncology Group clinical trial

Between 1980-84, the Radiation Therapy Oncology Group conducted a trial in patients with untreated, unresectable localized carcinomas of the pancreas. Patients were randomly chosen to receive either 6,400 cGy with photons, the equivalent dose with a combination of photons and neutrons (mixed-beam irradiation), or neutrons alone. A total of 49 cases were evaluable, of which 23 were treated with photons, 11 with mixed-beam therapy, and 15 with neutrons alone. The median survival time was 5.6 months with neutrons, 7.8 months with mixed-beam radiation, and 8.3 months with photons. The median local control time was 6.7 months with neutrons, 6.5 months with mixed-beam radiation, and 2.6 months with photons. These differences are not statistically significant. Evidence of moderate-to-life-threatening gastrointestinal or hepatic injury was present in three patients treated with neutrons and one patient treated with photons. The causes of this apparent difference are discussed. This study demonstrates there is no evidence to suggest that neutron irradiation, either alone or in combination with photon irradiation, produces better local control or survival rates than photon irradiation.

Neutron radiotherapy for malignant gliomas

Neutron radiotherapy has been used for patients with malignant gliomas for over a decade; a substantial number of patients have been treated to date. Pathologic analysis of surgical specimens posttreatment and autopsy specimens have documented an increased antitumor effect of neutrons against malignant gliomas, compared with photon irradiation. However, results of neutron trials to date have not shown a survival advantage over conventional radiotherapy for these patients. This article reviews current surgical, radiotherapeutic, and chemotherapeutic approaches to these tumors, the rationale for neutron treatment, and the results of trials of neutron radiotherapy conducted to date for patients with malignant gliomas.

Malignant glioma--a nemesis which requires clinical and basic investigation in radiation oncology

Malignant gliomas account for 40% of all central nervous system malignancies. These are essentially localized neoplastic tumors that have defied most treatment. In spite of improved techniques, surgery is unlikely to increase survival further since true cancer operations cannot be performed. Radiation therapy has made a significant difference in outcome. Investigation in radiation oncology is essential for further improvement in the treatment of these tumors. The pattern of failure is local tumor recurrence, but the method to overcome this resistance to treatment is not clear. Radiation therapy techniques and inherent radio-resistance have been considered as possible reasons for failure. With newer imaging procedures, the extent of tumor can be more accurately defined allowing improved treatment planning. Identifying an effective treatment program is more difficult. Studies have documented the beneficial effect of radiation therapy, but the optimal dose or fractionation schedule has not been determined. Whereas some studies have reported improved survival using higher radiation doses, others have reported no benefit. More recently, studies of multiple daily fractionation schedules have been conducted using two or three daily fractions. Equally confusing results have been reported. Histologically, these tumors have necrotic areas and may be radioresistant due to hypoxic cells. Treatment methods designed to overcome the radioprotective effect of hypoxia have yielded disappointing results. The addition of hypoxic cell sensitizers has not produced the expected improvement in outcome. Studies using neutron radiation therapy report tumor control but not improved survival. Radiobiologic information is now available which may contribute to our understanding of the response of these tumors to radiation. Further laboratory and clinical investigation is required. Carefully designed clinical trials are needed to test new treatment concepts, and all radiation oncologists should be prepared to participate in such clinical studies.

Chemotherapy following surgery for head and neck cancer. A Radiation Therapy Oncology Group Study

The feasibility of chemotherapy of three courses of cis-platin and 120-h 5-fluorouracil (5-FU) infusion after definitive surgery, followed by standard radiotherapy, in patients with resectable locally advanced head and neck cancer was carried out in Radiation Therapy Oncology Group (RTOG). Seventy-nine percent of the patients had stage IV cancer, 65% of the tumors were moderately differentiated, and primary sites were 38% oropharynx and 28% larynx. Toxicity to chemotherapy was acceptable, with no life-threatening side effects. Nausea and vomiting were the most common side effects (78%) and were severe in 26%; 30% of patients experienced had leukopenia, 22% had anemia, 13% had thrombocytopenia, and 9% had renal impairment--all of which were mild and reversible. In six patients, chemotherapy was not given for medical conditions or because of patient refusal. Of 23 patients started on cis-platin and 5-FU postsurgery, 18 (78%) completed all three courses. Ninety-six percent of the patients finished adequate radiotherapy according to the protocol. With minimum follow-up of 24 months, 62% of the patients were alive. Of the expired patients, 5 died from other causes, without evidence of recurrence at the time of their death. It is our conclusion that chemotherapy with cis-platin and 5-FU infusion following definitive surgery is feasible on the group level, and a Phase III trial comparing this combined modality therapy to standard treatment of surgery and post-operative radiotherapy is underway by the Head and Neck Cancer Intergroup.

Radiation Therapy Oncology Group (RTOG) studies in head and neck cancer

Since its foundation in 1971, the RTOG has conducted a successful clinical research program in head and neck mucosal squamous cell carcinoma with 22 treatment protocols and one registry study which combined have accumulated data on over 5,500 patients. The RTOG was the first multicenter group to evaluate neoadjuvant chemotherapy before definitive radiation with its methotrexate study. Although the study was negative, RTOG has since conducted five pilot or phase II studies of neoinduction or concurrent chemotherapy with radiation therapy in patients with inoperable tumors. The last study showed that radiation concurrent with cisplatinum was tolerable with a suggestion of increased antitumor effect. In patients with potentially resectable tumors, RTOG has completed a pilot study of combination chemotherapy administered either before or after the surgery with radiotherapy. Based upon its findings, the treatment sequence, surgery-chemotherapy-radiotherapy, was chosen as the experimental arm for a new phase III study. This study was subsequently adopted by the head and neck intergroup mechanism as its study (INT 0034/RTOG 8503). RTOG has investigated the optimal timing of radiotherapy with surgery. The 7303 study established that postoperative radiotherapy achieved significantly better locoregional control but not improved absolute survival. Approximately 30% of the patients on each arm failed to complete both modalities. Even when comparison is restricted to patients who completed both modalities, postoperative radiotherapy still produced the better locoregional control. Efforts to overcome the limitations imposed by tumor hypoxia through use of carbogen (95% O2 and 5% CO2) breathing or the radiosensitizer misonidazole during radiotherapy have been unsuccessful. In a phase I study, RTOG showed that 15 to 18 sessions of sensitized radiation can be safely delivered with the new radiosensitizer SR 2508 in contrast to only six such sessions with misonidazole. This promising radiosensitizer is now being tested in a phase III trial. RTOG has also investigated variations in fraction size, fraction number, and total radiation dose. In the 7102 study, split-course irradiation achieved equivalent antitumor results as compared to continuous daily irradiation but with less social alteration and cost to the patient. In the hyperfraction pilot study 7703, twice a day irradiation with 120 cGys up to 6,000 cGys proved to be tolerable.(ABSTRACT TRUNCATED AT 400 WORDS)

Combined radiation therapy and surgery in the management of advanced head and neck cancer: final report of study 73-03 of the Radiation Therapy Oncology Group

Between March 1973 and June 1979, patients with advanced operable squamous cell carcinoma of the supraglottic larynx or hypopharynx were randomly allocated to receive either preoperative radiation therapy (5,000 rad) or postoperative radiation therapy (6,000 rad). Patients with oral cavity or oropharynx lesions were randomly assigned either preoperative radiation, postoperative radiation, or definitive radiation therapy (6,500-7,000 rad), with surgery reserved for salvage if residual disease was present 6 weeks after completion of irradiation. Three hundred twenty patients were evaluable with a median follow-up of 60 months. Based on results in 277 patients across all four regions combined, locoregional control was significantly better for patients assigned to receive postoperative radiation therapy (65%) compared with those assigned to receive preoperative radiation therapy (48%, P = 0.04). This was due to a higher rate of both persistent and recurrent local and regional disease in the preoperative group. Survival also showed a trend to be better in the postoperative group (38%) compared with the preoperative group (33%, P = 0.10). Rates of severe surgical and radiation therapy complications were similar overall. Forty-three patients were evaluable for each of the three treatment regimens assigned to patients with oral cavity or oropharynx lesions. Due to the small number of patients available for this portion of the trial, the observed differences for overall survival (4-year percentage 33% overall; 30% preoperative, 36% postoperative, 33% definitive radiation therapy) and for locoregional control (45% overall; 43% preoperative, 52% postoperative, 38% definitive radiation therapy) were not statistically significant. The use of definitive radiation therapy with surgical rescue as an ethically justified alternative treatment for these tumors remains a question for further research.

An outcome study of the RTOG Cancer Control program

The Cancer Control program, funded by the National Cancer Institute, was initiated with the goal of involving community hospitals in multi-institutional clinical trials. The Radiation Therapy Oncology Group (RTOG) began participating in this program in 1976. This investigation compares the survival of patients treated by protocol in RTOG Full Member versus Cancer Control institutions between 1976 and 1985. The RTOG has 28 Full Members which are major treatment centers and enter at least 50 patients on RTOG protocols each year. The 11 Cancer Control members, which are mostly community hospitals, must enter at least 12 patients on RTOG protocols each year. A comparison of survival between Full Members and Cancer Control members was made for five RTOG studies. No difference in data quality or protocol compliance was observed for these studies between Cancer Control and Full Member institutions. Overall survival comparisons, as well as comparisons adjusted for prognostic factors, were made for each of the five studies. No differences in survival between Cancer Control and Full Members were observed in either analysis.

The manpower crisis facing radiation oncology

Data from several sources document that the number of radiation oncologists being trained is substantially above the number projected as recently as 1983. This paper addresses the manpower crisis facing radiation oncology and includes information on the supply of and need for specialists, as well as possible courses of action given current circumstances.

Fast neutron and mixed beam radiotherapy for inoperable non-small cell carcinoma of the lung. Results of an RTOG randomized study

From July 1979 through March 1984 the Radiation Therapy Oncology Group conducted a randomized study comparing fast neutron radiotherapy versus mixed beam (neutron/photon) radiotherapy versus conventional radiotherapy for patients with non-small cell carcinoma of the lung. Patients were either medically or technically inoperable. One hundred two evaluable patients were placed on the study. The radiation doses were approximately 60 Gy-equivalent on each arm. Patients were stratified according to size of primary, histology, Karnofsky performance status, and age distribution. Overall local response rates as measured by serial radiographs were the same on the three arms, and an actuarial analysis showed no significant differences in either median or long-term survival. However, for the subgroup of patients exhibiting a complete or partial tumor response at 6 months there was a suggestion of improved 3-year survival on the two experimental arms (mixed beam, 37%; neutrons, 25%; photons, 12%). The p value for the difference between the mixed beam and photon curves is 0.14 (two-sided test). The incidence of major complications was higher on the neutron and mixed beam arms. These complications included four cases of myelitis which are analyzed in detail. The results are placed in the context of other published work on the use of neutrons in the treatment of lung cancer.

Prognostic factors for loco/regional control and metastasis and the impact on survival

For the identification of predictive factors for local (head and neck) control and metastases and impact on survival in squamous cell cancer of the head and neck, we have used data from over 2000 patients from the Patterns of Care Study (PCS) and the Radiation Therapy Oncology Group (RTOG) studies. Complete local response (C.R.) is significantly related to T stage, N stage, general performance status (Karnofsky), and site of primary tumor. There is a strong association between T and N stage. T1N0 tumors showed a C.R. of 99%, whereas, T1N3 had a C.R. of 57%. T4N0 showed a C.R. of 75%, but this went down to 31% in the T4N3 lesions. Glottic tumors showed a C.R. of 96% versus the other sites, which ranged from 81% for the nasopharynx to 59% for the hypopharynx. Patients with a performance status (KPS) of less than 90% showed a C.R. of 60% versus 88% for AKPS 90% or higher. Absence of local recurrence after C.R. is significantly related to T stage, N stage, and the site of primary tumor (glottis versus the rest). The appearance of distant metastases is significantly related only to N stage and primary site. This relationship persists in control of loco/regional tumors. In Stages III & IV in non-glottic head and neck cancer, metastases as the cause of death play an increasingly important role. This can be as high as 30%. The appearance of new malignant tumors and death unrelated to cancer, that is, death related to lifestyle, assumes an important role in patients with advanced head and neck cancer. The number of advanced glottic larynx was too small to examine this question. The use of a surgical procedure in carcinomas of the anterior tongue and floor of the mouth was associated with a smaller percentage of infield recurrences at 2 years, than when radiation therapy alone was used (27% versus 88% p less than .01). The same observation was noted at 3 years in the glottic and supraglottic Stage III & IV tumors (p less than .01).

Evaluation of a neutron boost in head and neck cancer. Results of the randomized RTOG trial 78-08

Patients with untreated squamous cell cancer of the head and neck region were randomized to receive either a boost of 25-30 Gy using photon-beam irradiation (photons) or an equivalent boost using neutron-beam irradiation (neutrons). All patients received an initial 45-50 Gy of wide-field photon irradiation. A total of 57 patients was evaluable on the neutron arm and 58 were evaluable on the photon arm. The proportion of patients with complete responses was 60 and 64% on the neutron and photon arms, respectively. The locally disease-free proportion at 2 years was estimated to be 20 and 31%, and the 2-year survival was estimated to be 32 and 41%, respectively. These differences are not statistically significant. There was a higher rate of severe complications on the neutron arm, 16 versus 7%. Thus, there was no evidence that a neutron boost produces better initial tumor clearance, local tumor control, or survival than a photon boost, and it may produce more complications.