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L Coia

Publications and source records attributed to L Coia.

At least 19 recordsLinked to original sources
PubMed2000

Phase II, two-arm RTOG trial (94-11) of bischloroethyl-nitrosourea plus accelerated hyperfractionated radiotherapy (64.0 or 70.4 Gy) based on tumor volume (> 20 or < or = 20 cm(2), respectively) in the treatment of newly-diagnosed radiosurgery-ineligible glioblastoma multiforme patients.

PURPOSE: To compare survivorship, and acute and delayed toxicities following radiation therapy (RT) of radiosurgery-ineligible glioblastoma multiforme (GBM) patients treated with tumor volume-influenced, high-dose accelerated, hyperfractionated RT plus bischloroethyl-nitrosourea (BCNU), using prior RTOG malignant glioblastoma patients as historical controls. METHODS AND MATERIALS: One hundred four of 108 patients accrued from June 1994 through May 1995 from 26 institutions were analyzable. Patients were histologically confirmed with GBM, and previously untreated. Treatment assignment (52 patients/arm) was based on tumor mass (TM), defined as the product of the maximum diameter and greatest perpendicular dimension of the titanium-gadolinium-enhanced postoperative MRI: Arm A, 64 Gy, TM > 20 cm(2); or Arm B, 70.4 Gy, TM < or = 20 cm(2). Both Arms A and B received BCNU (80 mg/m(2), under hyperhydration) days 1-3, 56-58, then 4 cycles, each 8 weeks, for a total of 6 treatment series. RESULTS: During the 24 months immediately post-treatment, the overall median survival was 9.1 months in Arm A (64 Gy) and 11.0 months in Arm B (70.4 Gy). Median survival in recursive partitioning analysis (RPA) Class III/IV was 10.4 months in Arm A and 12.2 months in Arm B, while RPA Class V/VI was 7.6 months in Arm A and 6.1 months in Arm B. There were no grade 4 neurological toxicities in Arm A; 2 grade 4 neurological toxicities were observed in Arm B (1 motor deficit, 1 necrosis at 157 days post-treatment). CONCLUSION: This strategy of high-dose, accelerated hyperfractionated radiotherapy shortens overall RT treatment times while allowing dose escalation, and it provides the potential for combination with currently available, as well as newer, chemotherapy agents. Survival is comparable with previously published RTOG data, and toxicities are within acceptable limits.

Antineoplastic Agents, Alkylating↗
PubMed1998

Prognostic value of CA 19-9 levels in patients with carcinoma of the pancreas treated with radiotherapy.

PURPOSE: CA 19-9 has been identified as a tumor marker for pancreatic carcinoma and has been shown to have some utility in predicting outcome in surgically treated patients. The purpose of this study was to evaluate its usefulness as a prognostic indicator in patients treated with radiotherapy. MATERIALS AND METHODS: A retrospective review of all patients treated with radiotherapy of definitive intent (n = 104) for carcinoma of the pancreas at Fox Chase Cancer Center from 1980-1994 was undertaken. Patients were categorized into four groups: Planned preoperative radiation with resection (n = 25); planned preoperative radiation without successful resection (n = 35); postoperative radiation (n = 21); and radiation without planned resection (n = 23). For each group, except those treated without planned resection, median dose for external beam radiotherapy was 50.4 Gy (range = 21.6-63.0 Gy). Those in the remaining fourth group were treated with a median dose of 55.8 Gy (range = 36.0-60.4 Gy). 97% of patients in the first three groups were also treated with 5-FU-based chemotherapy, as were 61% of those in the fourth group. Pretreatment and follow-up CA 19-9 levels were available for 69 patients. RESULTS: Median survival time for all groups was 10 months (range = 1-67 months). Univariate analysis showed significant differences in survival among the groups: Preop with resection 22 months; preop without resection 10 months, postop 17 months; and without planned resection 12 months (p = 0.0005). Overall, patients who underwent resection had a median survival time of 19 months, compared to 11 months in those who did not (p = 0.0006). CA 19-9 level at diagnosis was found to be a significant prognostic indicator on univariate analysis, with a median survival time of 8 months in those having a level greater than the median of 680 U/ml, compared to 20 months in those who did not (p = 0.0003). Similarly, the posttreatment nadir was significant, with a median survival time of 11 months in those with levels above the median of 162.5 U/ml, vs. 26 months in those with levels below 162.5 U/ml (p = 0.001). The median survival time for patients whose CA 19-9 levels decreased in response to treatment by more than 75% was 23 months (range = 6-34 months) vs. 8 months (range = 3-21) in those with 75% or less response (p = 0.003). On stepwise multivariate analysis, pretreatment CA 19-9 level was found to be a significant predictor of survival (p = 0.005). Other potential indicators of outcome, including age, gender, KPS, prediagnosis weight loss, location of tumor, clinical TNM staging, size of lesion, vascular involvement on angiography, and sequence of radiation with respect to resection, were evaluated and were not found to be significant. CONCLUSION: CA 19-9 was demonstrated to be a useful prognostic indicator in patients treated with radiotherapy; other, more traditional, indicators of outcome were of less utility.

Aged↗
PubMed1998

Treatment systems guidelines for primary rectal cancer from the 1996 Patterns of Care Study.

PURPOSE: The Patterns of Care Rectal Cancer Committee was formed to develop consensus recommendations for patients with adenocarcinoma of the rectum limited to the pelvis. METHODS AND MATERIALS: The Committee was composed of a multidisciplinary group of oncologists, and clinical scenarios were chosen to address most of the major treatment controversies in the combined modality treatment of rectal cancer. A literature search was then conducted and the major articles were identified. A modified Delphi technique was used to arrive at consensus. Serial surveys were conducted by distributing questionnaires to the Committee members to consolidate expert opinion. Voting was conducted using a scoring system and opinions were unified to the highest degree possible. RESULTS: Consensus voting was performed for 4 clinical scenarios. Acceptability ratings for treatment were grouped into 3 broad categories: not acceptable, acceptable, and most acceptable. Based on the treatment options, a decision tree was developed that reflects the consensus of the committee. CONCLUSION: These options may help guide treatment decisions in rectal cancer.

Adenocarcinoma↗
PubMed1998

Radiation therapy for rectosigmoid and rectal cancer: results of the 1992-1994 Patterns of Care process survey.

PURPOSE: To determine the US national practice standards for patients with adenocarcinoma of the rectum treated in radiation oncology facilities. MATERIALS AND METHODS: A national survey of 57 institutions identified 507 eligible patients who received radiation therapy as a component of their treatment for rectal cancer. A stratified two-stage cluster sampling with simple random sampling at each stage for each stratum was used and on-site surveys were performed. RESULTS: Of the 507 patients, 378 (75%) received postoperative therapy, 110 (22%) received preoperative therapy, 17 (2%) received both preoperative and postoperative therapy, and less than 0.5% received intraoperative radiation alone. To more accurately assess the utilization of modern radiation techniques as well as recommendations of the National Cancer Institute (NCI)-sponsored, randomized, postoperative, adjuvant combined modality therapy rectal cancer trials into current practice, the analysis was limited to the 243 (48%) patients with tumor, node, and metastasis staging system classification T3 and/or N1-2M0 disease who underwent conventional surgery with negative margins. Although only 7% were treated on a clinical trial, 90% received chemotherapy for a median of 21 weeks. Most were treated with modern radiation treatment techniques. In contrast, techniques to identify and help exclude the small bowel from the radiation field were not routinely used. CONCLUSION: Despite the fact that only 7% of patients with T3 and/or N1-2M0 disease were treated on a clinical trial, such trials appear to have resulted in a positive influence on the standard of practice within the oncology community. Although there are still some deficiencies, the majority of these patients received combined modality therapy and were treated with modern radiation therapy techniques.

Adenocarcinoma↗
PubMed1996

Role of mitomycin in combination with fluorouracil and radiotherapy, and of salvage chemoradiation in the definitive nonsurgical treatment of epidermoid carcinoma of the anal canal: results of a phase III randomized intergroup study.

PURPOSE: Definitive chemoradiation (CR) has replaced radical surgery as the preferred treatment of epidermoid carcinoma of the anal canal. To determine the importance of mitomycin (MMC) in the standard CR regimen and to assess the role of salvage CR in patients who have residual tumor following CR, a phase III randomized trial was undertaken by the Radiation Therapy Oncology Group (RTOG)/Eastern Cooperative Oncology Group (ECOG). PATIENTS AND METHODS: Between August 1988 and December 1991, 310 patients were randomized to receive either radiotherapy (RT) and fluorouracil (5-FU) or radiotherapy, 5-FU, and MMC. Of 291 assessable patients, 145 received 45 to 50.4 Gy of pelvic RT plus 5-FU at 1,000 mg/m2/d for 4 days, and 146 received RT, 5-FU, and MMC (10 mg/m2 per dose for two doses). Patients with residual tumor on posttreatment biopsy were treated with a salvage regimen that consisted of additional pelvic RT (9 Gy), 5-FU, and cisplatin (100 mg/m2). RESULTS: Posttreatment biopsies were positive in 15% of patients in the 5-FU arm versus 7.7% in the MMC arm (P = .135). At 4 years, colostomy rates were lower (9% v 22%; P = .002), colostomy-free survival higher (71% v 59%; P = .014), and disease-free survival higher (73% v 51%; P = .0003) in the MMC arm. A significant difference in overall survival has not been observed at 4 years. Toxicity was greater in the MMC arm (23% v 7% grade 4 and 5 toxicity; P < or = .001). Of 24 assessable patients who underwent salvage CR, 12 (50%) were rendered disease-free. CONCLUSION: Despite greater toxicity, the use of MMC in a definitive CR regimen for anal cancer is justified, particularly in patients with large primary tumors. Salvage CR should be attempted in patients with residual disease following definitive CR before resorting to radical surgery.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Preoperative chemoradiation for adenocarcinoma of the pancreas and duodenum.

PURPOSE: This study was designed to evaluate the effects of preoperative chemoradiation on resectability, response, local control, and survival in patients with local or local-regional involvement from carcinoma of the pancreas or cancer of the duodenum and to assess the associated toxicity of such treatment. METHODS AND MATERIALS: This prospective pilot study of preoperative chemoradiation was initiated in 1986 for patients with clinical evidence of adenocarcinoma of the pancreas or duodenum without evidence of distant metastases. Radiation was given at 1.8 Gy per day to a total dose of 50.4 Gy. Two cycles of chemotherapy were given concurrent with radiation. On days 2-5 and 29-32, 5-fluorouracil (1 gm/m2/24 h x 4 days) was given, while mitomycin-C (10 mg/m2) was given on day 2 only. Surgical resection was 4-6 weeks following completion of chemoradiation. Thirty-one patients (17 male and 14 female) were entered on the protocol with a median potential follow-up of 4.5 years (range 6 months to 7.5 years). The median age was 64 years (range 32-73 years). Twenty-seven patients had pancreatic cancer (25 head, two body), while four patients had carcinoma arising from the duodenum. Twenty-one patients were initially judged to be unresectable and ten potentially resectable prior to chemoradiation. RESULTS: Twenty-nine of 31 patients completed the entire course of radiation and both cycles of chemotherapy. Acute toxicity from chemoradiation consisted of nausea, vomiting, diarrhea, stomatitis, or hematologic suppression which was moderate to severe (Grade 3 or 4) in seven patients (23%). One patient died of sepsis following the first week of therapy. Seventeen patients (55%) underwent curative resection with subtotal or total pancreatectomy or Whipple resection (four duodenum, 13 pancreas) and two (2/17) had pathologic nodal involvement, while (0/17) none had involved margins. A complete pathologic response was seen in all four (4/4) patients with duodenal cancer and in none (0/13) with pancreatic cancer who underwent resection. The median postoperative hospitalization stay was 22 days (range 4-144 days). Of 17 patients who underwent curative resection, there were two postoperative mortalities (12%). Late complications have included abscess, one; and nonmalignant ascites, five. Ten of the 31 patients are alive. For patients with pancreatic cancer the median survival is 9 months, while survival at 1 year and 3 years are 36% and 19% overall and 60% and 43% at 1 and 3 years for those undergoing resection. Six of the 27 patients (22%) with pancreatic cancer are alive without recurrence. All four patients with duodenal cancer are alive without recurrence (12 months, 23 months, 35 months, 90 months). CONCLUSION: Preoperative chemoradiation for cancer of the pancreas and duodenal region was relatively well-tolerated and enhanced resectability and downstaging of nodal metastases were suggested. The 3-year survival, particularly in patients who underwent resection, was high. For these reasons the applicability of this treatment regimen for pancreatic cancer is presently being studied in a group-wide multi-institutional Phase II trial. Chemoradiation for duodenal cancer has produced a complete pathologic response in all patients and survival has been excellent, suggesting efficacy of this regimen for duodenal cancer.

Adenocarcinoma↗
PubMed1994

Evaluation and treatment of patients receiving radiation for cancer of the rectum or sigmoid colon in the United States: results of the 1988-1989 Patterns of Care Study process survey.

PURPOSE: For the first time, a Patterns of Care Study (PCS) was conducted in 1989 to determine the national practice standards of radiation oncologists in evaluating and treating adenocarcinoma of the rectum and sigmoid colon. MATERIALS AND METHODS: A national survey of 73 institutions using two-stage cluster sampling was conducted, and specific information on 408 patients from 69 facilities with adenocarcinoma of the rectum and sigmoid colon who received radiation as part of definitive or adjuvant management was collected. RESULTS: Using the modified Astler-Coller (MAC) pathologic staging system, the stage distribution was as follows: A, 0.5%; B1, 4.4%; B2, 23.5%; B3, 5.1%; C1, 8.9%; C2, 30.2%; and C3, 6.6%. Preoperative radiation was used in 29% of patients, but the total dose was greater than 40 Gy in only 20%. Seventy-three percent of patients received postoperative radiation, with approximately 4% receiving combined preoperative and postoperative radiation. Chemotherapy was administered to 44% of patients overall, representing 55% of patients with disease through the bowel wall and/or involving lymph nodes. Only 37% of all patients received chemotherapy concurrent with radiation. An abdominoperineal resection was used in 43%; a low anterior resection was used in 43% as well, while 5% underwent other types of bowel resection. Approximately 8% of patients were treated with a local curative procedure less than bowel resection (eg, local excision, endoscopic resection, fulguration, or contact radiation). At least one third of patients had interruption in their pelvic irradiation of greater than 3 days. There was no statistically significant difference in the frequency of treatment interruptions by dose per fraction or whether chemotherapy was given concurrent with radiation. There was no significant difference in total dose delivered to patients staged B2 and higher treated without chemotherapy compared with concurrent chemotherapy and radiation. Also, there was no significant difference in total dose delivered to patients with B1 and B2, or C1 and C2 versus B3 or C3 cancer. CONCLUSION: This study was conducted on patients treated just before the 1990 National Institutes of Health consensus guidelines issued on the management of colon and rectal cancer. This study indicates that the minority of patients treated with radiation in 1988 and 1989 received concurrent chemoradiation, as currently recommended. Additionally, insofar as present studies are investigating important issues such as the use of sphincter-sparing procedures, preoperative radiation and chemotherapy, and the importance of radiation dose and scheduling with chemotherapy, the information provided by this study will serve as a useful baseline to track future changes in rectal cancer evaluation and management.

Adenocarcinoma↗
PubMed1993

Anatomy of the celiac axis and superior mesenteric artery and its significance in radiation therapy.

PURPOSE: In the radiation therapy of upper gastrointestinal malignancies, treatment of lymph nodes in the region of the celiac axis and superior mesenteric axis is often mandated. This study was undertaken to determine the relationship of the celiac axis and superior mesenteric arteries to the vertebral bodies--the radiographically visualized reference structures during simulation. METHODS AND MATERIALS: Twenty-three celiac angiograms and 24 superior mesenteric angiograms performed preoperatively in 24 patients treated at the University of Pennsylvania from 1984 to 1989 for pancreatic carcinoma were examined. The location of the origin of the celiac and superior mesenteric arteries was determined in each case. RESULTS: In 48% of the celiac angiograms, the celiac axis arose from the aorta high at the pedicle of the T-12 vertebral body, contrary to the common belief that the celiac axis arises near the T12-L1 interspace. The superior mesenteric artery arose at the level of L-1 in 83% of the 24 angiograms and below the pedicle of L-1 in 5 (21%). However, none arose below the L1-2 interspace. CONCLUSION: The variability demonstrated in the levels from which these vessels arise strongly suggests individualized treatment planning, including angiographic, CT or MRI data should be performed if tight margins are used. These studies would additionally optimize treatment of the tumor bed. Consideration for dose at field edges (i.e., "buildup") and day to day variation in set-up is required in determining the field borders. Treatment volumes tightly encompassing T12 and L1 could risk undertreating regional lymph nodes associated with these vessels.

Angiography↗
PubMed1992

Interruptions adversely affect local control and survival with hyperfractionated radiation therapy of carcinomas of the upper respiratory and digestive tracts. New evidence for accelerated proliferation from Radiation Therapy Oncology Group Protocol 8313.

Hyperfractionated radiation therapy (HFX) attempts to overcome tumor proliferation during treatment by permitting higher total doses in the same overall time as standard fractionation. Whereas interruptions, including splits, reduce local control with standard fractionation in carcinoma of the upper respiratory and digestive tracts, HFX might compensate for interruptions. Patients were randomized to receive total doses of 6720, 7200, 7680, and 8160 cGy, using 120 cGy twice daily, 5 days per week. Those analyzed received +/- 4% of assigned total dose and lived 90 days or more. Treatment was completed within 5 days of the time specified for each treatment arm in 233 patients; 48, 80, and 131 patients had delays 14, 10, and 5 days or more, respectively. Locoregional control and survival were significantly (P less than or equal to 0.03) reduced with delays of 5 days or more when corrected for prognostic factors. Late effects of radiation therapy were not affected by interruptions. These data support the hypothesis that proliferation (possibly accelerated) of tumor clonogens during treatment influences the outcome.

Aged↗
PubMed1992

A phase I study of WR-2721 in combination with total body irradiation (TBI) in patients with refractory lymphoid malignancies.

This Phase I study was designed to establish the maximum tolerated dose (MTD) of WR-2721 when given twice weekly with total body irradiation (TBI) in the treatment of patients with advanced refractory lymphoid malignancies and to define the toxicities of this combination and schedule. Patients eligible for this study had advanced recurrent indolent non-Hodgkin's lymphoma (NHL) or chronic lymphocytic leukemia (CLL). Patients had symptomatic or progressive disease, a performance status of 0, 1, or 2, and adequate bone marrow, hepatic, and renal function. Only patients failing one or two regimens of prior chemotherapy were eligible. Patients who had received prior extended field irradiation were ineligible. Patients received TBI twice weekly (Tuesday and Friday) to a total of 10 doses at 15 cGy/fx. WR-2721 was given intravenously over 15 min beginning 30 min before irradiation. The escalation of WR-2721 was Level 1: 740 mg/m2 and Level 2: 910 mg/m2. The MTD of WR-2721 was that dose which produced predictable and reversible toxicity and would not interfere with patient well-being. Seven patients were entered onto the study, three at 740 mg/m2 and four at 910 mg/m2. Five patients had CLL and two patients small lymphocytic NHL. No patient had hypotension or nausea requiring reduction in dose level or even interruption of infusion of WR-2721. At 740 mg/m2 no grade 3 or 4 toxicities related to WR-2721 were observed, but two patients could not complete treatment because of TBI-induced prolonged thrombocytopenia following treatments 5 and 8. One patient completed all 10 treatments. At 910 mg/m2 of WR-2721, two patients requested removal from study because of malaise, one after 5 cycles and one after 7 cycles. One patient completed all 10 treatments. One patient was treated with a modified schedule of 7 treatments of 20 cGy/fx and tolerated and completed all treatments but developed significant thrombocytopenia following completion of treatment. No patients had disease progression during treatment. The median survival was 11 months. This study indicates that WR-2721 given at 910 mg/m2 twice weekly with TBI is well tolerated for at least 5 treatments and that 910 mg/m2 of WR-2721 is the MTD with this regimen. In view of the importance of total radiation dose in achieving a response with TBI, a dose escalation study of TBI with 910 mg/m2 of WR-2721 should be performed in patients with indolent non-Hodgkin's lymphoma.

Amifostine↗
PubMed1992

Treatment strategies in advanced and metastatic cancer: differences in attitude between the USA, Canada and Europe.

Six-hundred and forty four radiation therapists from 21 European countries, Canada, and the USA responded to a questionnaire regarding the management of three cases of advanced cancer. The cases were a 64-year-old man with brain metastases from small cell carcinoma of the lung; a 64-year-old woman with bone metastases from carcinoma of the breast and a 59-year-old man with squamous cell carcinoma of the bronchus and mediastinal nodes. There was variation as to the perceived prognosis and appropriate aims of therapy, particularly for the case of squamous cell carcinoma of the bronchus. The total dose and number of fractions could be related to the perceived aims and expectations of treatment, for example, those aiming to extend life gave higher doses of radiotherapy and those aiming only to relieve symptoms gave lower. Similarly, those describing treatment as radical and estimating longer survival gave higher doses and more fractions than those treating palliatively. Variations in the role of the radiation oncologist in the management of advanced and metastatic cancer in the USA, Canada and Europe are discussed.

Attitude of Health Personnel↗
PubMed1991

Free magnesium levels in normal human brain and brain tumors: 31P chemical-shift imaging measurements at 1.5 T.

We have studied a series of normal subjects and patients with brain tumors, by using 31P three-dimensional chemical shift imaging to obtain localized 31P spectra of the brain. A significant proportion of brain cytosolic ATP in normal brain is not complexed to Mg2+, as indicated by the chemical shift delta of the beta-P resonance of ATP. The ATP beta-P resonance position in brain thus is sensitive to changes in intracellular free Mg2+ concentration and in the proportion of ATP complexed with Mg because this shift lies on the rising portion of the delta vs. Mg2+ titration curve for ATP. We have measured the ATP beta-P shift and compared intracellular free Mg2+ concentration and fractions of free ATP for normal individuals (n = 6) and a limited series of patients with brain tumors (n = 5). In four of the five spectra obtained from brain tissue containing a substantial proportion of tumor, intracellular free Mg2+ was increased, and the fraction of free ATP was decreased, compared with normal brain.

Adenosine Triphosphate↗
PubMed1991

Tolerance of normal tissue to therapeutic irradiation.

The importance of knowledge on tolerance of normal tissue organs to irradiation by radiation oncologists cannot be overemphasized. Unfortunately, current knowledge is less than adequate. With the increasing use of 3-D treatment planning and dose delivery, this issue, particularly volumetric information, will become even more critical. As a part of the NCI contract N01 CM-47316, a task force, chaired by the primary author, was formed and an extensive literature search was carried out to address this issue. In this issue. In this manuscript we present the updated information on tolerance of normal tissues of concern in the protocols of this contract, based on available data, with a special emphasis on partial volume effects. Due to a lack of precise and comprehensive data base, opinions and experience of the clinicians from four universities involved in the contract have also been contributory. Obviously, this is not and cannot be a comprehensive work, which is beyond the scope of this contract.

Bone and Bones↗
PubMed1991

Three-dimensional photon treatment planning for carcinoma of the nasopharynx.

The role of 3-D treatment planning for carcinoma of the nasopharynx was assessed in a four institution study. Two patients were worked up and had an extensive number of CT scans on which target volumes and normal tissues were defined. Treatment planning was then performed using state of the art dose planning systems for these patients to assess the value of the new technology. In general, it was demonstrated that multi-field conformal plans could achieve good tumor dose coverage, while at the same time reducing normal tissue doses, compared to standard treatment planning techniques. The role of inhomogeneity corrections, beam energy, and the use of CT vs. simulation films for defining target volumes were also discussed. In addition, techniques to evaluate 3-D plans for the nasopharynx were considered, and some analysis of this problem is presented in this paper.

Adult↗
PubMed1991

Three-dimensional photon treatment planning in carcinoma of the larynx.

The role of three-dimensional (3-D) treatment planning in the definitive treatment of carcinoma of the larynx with radiation was evaluated at four institutions as part of an NCI contract. A total of 30 different treatment approaches were devised for two patients with larynx cancer. CT scans were obtained for both patients and various treatment planning tools were employed to optimize beam arrangements and to evaluate the resulting dose distribution. The effect on dose distribution of a number of factors was also examined: 1) the use of dose calculation algorithms which correct for tissue inhomogeneities, 2) the variation of the CT numbers used for inhomogeneity corrections to simulate inaccuracies in the knowledge of the CT numbers, and 3) the modification of beam energy. A multitude of data was used in plan evaluation and a numerical score was given to each plan to estimate the tumor control probability and the normal tissue complication probability. We found 3-D treatment planning to be of potential value in optimizing treatment plans in larynx cancer. Improved target coverage was achieved when complete information describing 3-D geometry of the anatomy was utilized. In some cases, the treatment planning tools employed, such as the beam's eye view, helped devise novel beam arrangements which were useful alternatives to standard techniques. We found little effect of change in CT number on dose distributions. A comparison between dose distributions calculated with tissue inhomogeneity corrections to those calculated without this correction showed little difference. We did find some improvement in the dose to the primary tumor volume at lower beam energies, but with an increased larynx volume potentially receiving doses above tolerance.

Adult↗