William Small

Clinical practice guidelines in oncology

Ductal carcinoma in situ (DCIS) of the breast represents a heterogeneous group of neoplastic lesions in the breast ducts. The goal for management of DCIS is to prevent the development of invasive breast cancer. This manuscript focuses on the NCCN Guidelines Panel recommendations for the workup, primary treatment, risk reduction strategies, and surveillance specific to DCIS.

Long-term outcome in patients with a pathological complete response after chemoradiation for rectal cancer: a pooled analysis of individual patient data

BACKGROUND Locally advanced rectal cancer is usually treated with preoperative chemoradiation. After chemoradiation and surgery, 15-27% of the patients have no residual viable tumour at pathological examination, a pathological complete response (pCR). This study established whether patients with pCR have better long-term outcome than do those without pCR. METHODS In PubMed, Medline, and Embase we identified 27 articles, based on 17 different datasets, for long-term outcome of patients with and without pCR. 14 investigators agreed to provide individual patient data. All patients underwent chemoradiation and total mesorectal excision. Primary outcome was 5-year disease-free survival. Kaplan-Meier survival functions were computed and hazard ratios (HRs) calculated, with the Cox proportional hazards model. Subgroup analyses were done to test for effect modification by other predicting factors. Interstudy heterogeneity was assessed for disease-free survival and overall survival with forest plots and the Q test. FINDINGS 484 of 3105 included patients had a pCR. Median follow-up for all patients was 48 months (range 0-277). 5-year crude disease-free survival was 83.3% (95% CI 78.8-87.0) for patients with pCR (61/419 patients had disease recurrence) and 65.6% (63.6-68.0) for those without pCR (747/2263; HR 0.44, 95% CI 0.34-0.57; p<0.0001). The Q test and forest plots did not suggest significant interstudy variation. The adjusted HR for pCR for failure was 0.54 (95% CI 0.40-0.73), indicating that patients with pCR had a significantly increased probability of disease-free survival. The adjusted HR for disease-free survival for administration of adjuvant chemotherapy was 0.91 (95% CI 0.73-1.12). The effect of pCR on disease-free survival was not modified by other prognostic factors. INTERPRETATION Patients with pCR after chemoradiation have better long-term outcome than do those without pCR. pCR might be indicative of a prognostically favourable biological tumour profile with less propensity for local or distant recurrence and improved survival. FUNDING None.

Radiation-induced lung injury

Radiation therapy (RT) for thoracic-region tumors often causes lung injury. The incidence of lung toxicity depends on the method of assessment (eg, radiographs, patients symptoms, or functional endpoints such as pulmonary function tests). Three-dimensional (3D) treatment planning tools provide dosimetric predictors for the risk of symptomatic RT-induced lung injury and allow for beams to be selected to minimize these risks. A variety of cytokines have been implicated as indicators/mediators of lung injury. Recent work suggests that injury-associated tissue hypoxia perpetuates further injury. Sophisticated planning/delivery methods, such as intensity modulation, plus radioprotectors such as amifostine, hold promise to reduce the incidence of RT-induced lung injury.

A multi-institutional phase II trial of preoperative full-dose gemcitabine and concurrent radiation for patients with potentially resectable pancreatic carcinoma

BackgroundWe report the results of a multi-institutional phase II trial that used preoperative full-dose gemcitabine and radiotherapy for patients with potentially resectable pancreatic carcinoma.MethodsPatients were treated before surgery with three cycles of full-dose gemcitabine (1000 mg/m2 intravenously), with radiation during the second cycle (36 Gy in daily 2.4-Gy fractions). Patients underwent surgery 4 to 6 weeks after the last gemcitabine infusion.ResultsThere were 10 men and 10 women, with a median age of 58 years (range, 50–80 years). Nineteen patients (95%) completed therapy without interruption, and one experienced grade 3 gastrointestinal toxicity. The mean weight loss after therapy was 4.0%. Of 20 patients taken to surgery, 17 (85%) underwent resections (16 pancreaticoduodenectomies and 1 distal pancreatectomy). The complication rate was 24%, with an average length of stay of 13.5 days. There were no operative deaths. Pathologic analysis revealed clear margins in 16 (94%) of 17 and uninvolved lymph nodes in 11 (65%) of 17 specimens. One specimen contained no residual tumor, and three specimens revealed only microscopic foci of residual disease. With a median follow-up of 18 months, 7 (41%) of the 17 patients with resected disease are alive with no recurrence, 3 (18%) are alive with distant metastases, and 7 (41%) have died.ConclusionsPreoperative gemcitabine/radiotherapy is well tolerated and safe when delivered in a multi-institutional setting. This protocol had a high rate of subsequent resection, with acceptable morbidity. The high rate of negative margins and uninvolved nodes suggests a significant tumor response. Preliminary survival data are encouraging. This regimen should be considered in future neoadjuvant trials for pancreatic cancer.

Consensus Guidelines for Delineation of Clinical Target Volume for Intensity-Modulated Pelvic Radiotherapy for the Definitive Treatment of Cervix Cancer

PURPOSE Accurate target definition is vitally important for definitive treatment of cervix cancer with intensity-modulated radiotherapy (IMRT), yet a definition of clinical target volume (CTV) remains variable within the literature. The aim of this study was to develop a consensus CTV definition in preparation for a Phase 2 clinical trial being planned by the Radiation Therapy Oncology Group. METHODS AND MATERIALS A guidelines consensus working group meeting was convened in June 2008 for the purposes of developing target definition guidelines for IMRT for the intact cervix. A draft document of recommendations for CTV definition was created and used to aid in contouring a clinical case. The clinical case was then analyzed for consistency and clarity of target delineation using an expectation maximization algorithm for simultaneous truth and performance level estimation (STAPLE), with kappa statistics as a measure of agreement between participants. RESULTS Nineteen experts in gynecological radiation oncology generated contours on axial magnetic resonance images of the pelvis. Substantial STAPLE agreement sensitivity and specificity values were seen for gross tumor volume (GTV) delineation (0.84 and 0.96, respectively) with a kappa statistic of 0.68 (p < 0.0001). Agreement for delineation of cervix, uterus, vagina, and parametria was moderate. CONCLUSIONS This report provides guidelines for CTV definition in the definitive cervix cancer setting for the purposes of IMRT, building on previously published guidelines for IMRT in the postoperative setting.

Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

PURPOSE To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. METHODS AND MATERIALS One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The following were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. RESULTS The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, Adnexa_R, Adnexa_L, Prostate, SeminalVesc, PenileBulb, Femur_R, and Femur_L. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. CONCLUSIONS Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research.

Adverse reactions to intravenous iodinated contrast media: a primer for radiologists

Adverse reactions to intravenous iodinated contrast media may be classified as general and organ-specific, such as contrast-induced nephrotoxicity. General adverse reactions may be subclassified into acute and delayed types. Acute general adverse reactions can range from transient minor reactions to life-threatening severe reactions. Non-ionic contrast media have lower risk of mild and moderate adverse reactions. However, the risk of fatal reactions is similar for ionic and non-ionic contrast media. Adequate preprocedure evaluation should be performed to identify predisposing risk factors. Prompt recognition and treatment of acute adverse reactions is crucial. Risk of contrast induced nephrotoxicity can be reduced by use of non-ionic contrast media, less volume of contrast, and adequate hydration. The radiologist can play a pivotal role by being aware of predisposing factors, clinical presentation, and management of adverse reactions to contrast media.

RTOG 9804: A Prospective Randomized Trial for Good-Risk Ductal Carcinoma In Situ Comparing Radiotherapy With Observation

PURPOSE The Radiation Therapy Oncology Group 9804 study identified good-risk patients with ductal carcinoma in situ (DCIS), a breast cancer diagnosis found frequently in mammographically detected cancers, to test the benefit of radiotherapy (RT) after breast-conserving surgery compared with observation. PATIENTS AND METHODS This prospective randomized trial (1998 to 2006) in women with mammographically detected low- or intermediate-grade DCIS, measuring less than 2.5 cm with margins ≥ 3 mm, compared RT with observation after surgery. The study was designed for 1,790 patients but was closed early because of lower than projected accrual. Six hundred thirty-six patients from the United States and Canada were entered; tamoxifen use (62%) was optional. Ipsilateral local failure (LF) was the primary end point; LF and contralateral failure were estimated using cumulative incidence, and overall and disease-free survival were estimated using the Kaplan-Meier method. RESULTS Median follow-up time was 7.17 years (range, 0.01 to 11.33 years). Two LFs occurred in the RT arm, and 19 occurred in the observation arm. At 7 years, the LF rate was 0.9% (95% CI, 0.0% to 2.2%) in the RT arm versus 6.7% (95% CI, 3.2% to 9.6%) in the observation arm (hazard ratio, 0.11; 95% CI, 0.03 to 0.47; P < .001). Grade 1 to 2 acute toxicities occurred in 30% and 76% of patients in the observation and RT arms, respectively; grade 3 or 4 toxicities occurred in 4.0% and 4.2% of patients, respectively. Late RT toxicity was grade 1 in 30%, grade 2 in 4.6%, and grade 3 in 0.7% of patients. CONCLUSION In this good-risk subset of patients with DCIS, with a median follow-up of 7 years, the LF rate was low with observation but was decreased significantly with the addition of RT. Longer follow-up is planned because the timeline for LF in this setting seems protracted.

Automatic Patient Centering for MDCT: Effect on Radiation Dose

OBJECTIVE The purpose of this study was to determine with phantom and patient imaging the effect of an automatic patient-centering technique on the radiation dose associated with MDCT. SUBJECTS AND METHODS A 32-cm CT dose index (CTDI) phantom was scanned with 64-MDCT in three positions: gantry isocenter and 30 and 60 mm below the isocenter of the scanner gantry. In each position, surface, peripheral, and volume CTDIs were estimated with a standard 10-cm pencil ionization chamber. The institutional review board approved the study with 63 patients (36 men, 27 women; mean age, 51 years; age range, 22-83 years) undergoing chest (n = 18) or abdominal (n = 45) CT using the z-axis automatic exposure control technique. Each patient was positioned according to the region being scanned and then was centered in the gantry. Before scanning of a patient, automatic centering software was used to estimate patient off-centering and percentage of dose reduction with optimum recentering. Data were analyzed with linear correlation and the Students t test. RESULTS Peripheral and surface CTDIs increased approximately 12-18% with 30-mm off-center distance and 41-49% with 60-mm off-center distance. Approximately 95% (60/63) of patients were not positioned accurately in the gantry isocenter. The mean radiation dose saving with automatic centering of all patients was 13.0% +/- 0.9% (range, 2.6-29.9%). There was strong correlation between off-center distance and percentage of surface CTDI reduction with recentering of patients in the gantry isocenter (r2 = 0.85, p < 0.0001). CONCLUSION Surfaces doses can be reduced if radiologic technologists can better center patients within the CT gantry. Automatic centering technique can help in optimum patient centering and result in as much as 30% reduction in surface dose.

Full-Dose Gemcitabine With Concurrent Radiation Therapy in Patients With Nonmetastatic Pancreatic Cancer: A Multicenter Phase II Trial

PURPOSE Gemcitabine is effective in the treatment of pancreatic cancer and is a potent radiosensitizer. This study assessed safety and efficacy of full-dose gemcitabine administered before and during concurrent three-dimensional conformal radiation (3D-CRT) in patients with nonmetastatic pancreatic cancer. PATIENTS AND METHODS During cycles 1 and 3, patients received gemcitabine at 1,000 mg/m(2) on days 1 and 8 of each 21-day cycle. Cycle 2 included the same dose of gemcitabine on days 1, 8, and 15 of a 28-day cycle with concurrent 3D-CRT at 36 Gy, administered in 15 fractions of 2.4 Gy, over 3 weeks. Resectable patients underwent surgery 4 to 6 weeks after treatment. The primary objective was evaluation of toxicity. Tumor response, CA 19-9, and 1-year survival were also assessed. RESULTS Forty-one patients enrolled at six institutions between April 2002 and October 2003. Among the 39 treated patients, the most common toxicities were grade 3 neutropenia (12.8%), grade 3 nausea (10.3%), and grade 3 vomiting (10.3%). The response rate was 5.1% and disease control rate was 84.6%. Mean post-treatment CA 19-9 levels (228 +/- 347 U/mL) were significantly (P = .006) reduced compared with pretreatment levels (1,241 +/- 2,124 U/mL). Thirteen (81%) of 16 patients initially judged resectable, three (33%) of nine borderline-resectable patients, and one (7%) of 14 unresectable patients underwent resection after therapy. One-year survival rates were 73% for all patients, 94% for resectable patients, 76% for borderline-resectable patients, and 47% for unresectable patients. CONCLUSION Full-dose gemcitabine with concurrent radiotherapy was well tolerated and active. Evaluation of this regimen in a larger, randomized trial for patients with resectable or borderline-resectable disease may be warranted.