A biomechanical study on the effect of lengthening magnitude on spine off-loading in magnetically controlled growing rod surgery: Implications on lengthening frequency.

Purpose: To assess whether the magnitude of lengthening in magnetically controlled growing rod (MCGR) surgeries has an immediate or delayed effect on spinal off-loading. Methods: 9 whole porcine spines were instrumented using two standard MCGRs from T9 to L5. Static compression testing using a mechanical testing system (MTS) was performed at three MCGR lengthening stages (0 mm, 2 mm, and 6 mm) in each spine. At each stage, five cycles of compression at 175N with 25 min of relaxation was carried out. Off-loading was derived by comparing the load sustained by the spine with force applied by the MTS to the spine. Micro-CT imaging was subsequently performed. Results: The mean load sustained by the vertebral body before lengthening was 39.69N, and immediately after lengthening was 25.12N and 19.91N at 2 mm and 6 mm lengthening, respectively; decreasing to 10.07N, 8.31N, and 8.17N after 25 minutes of relaxation, at 0 mm, 2 mm, and 6 mm lengthening stages, respectively. There was no significant difference in off-loading between 2 mm and 6 mm lengthening stages, either instantaneously (p = 0.395) or after viscoelastic relaxation (p = 0.958). CT images showed fractures/separations at the level of pedicle screws in six spines and in the vertebral body's growth zone in five spines after 6 mm MCGR lengthening. Conclusion: This study demonstrated MCGRs cause significant off-loading of the spine leading to stress shielding. 6 mm of lengthening caused tissue damage and microfractures in some spines. There was no significant difference in spine off-loading between 2 mm and 6 mm MCGR lengthening, either immediately after lengthening or after viscoelastic relaxation.

Not All Gymnastic Exercises Are Suitable for Everyone: An Uncommon Cause of Thoracic Outlet Syndrome: A Case Report.

CASE: A 34-year-old man spontaneously presented with bilateral thoracic outlet syndrome over 1 year. He was a gymnast active in rowing and weightlifting, with "slanted" shoulders, narrowed costoclavicular spaces, and well-developed scalene muscles. Imaging revealed fractures of multiple bilateral upper ribs in various degrees of nonunion. The patient's symptoms improved after activity modification and physiotherapy. CONCLUSIONS: Atraumatic spontaneous rib fracture-nonunions are an uncommon cause of thoracic outlet syndrome; this diagnosis should be considered in physically active patients presenting with typical symptoms with atypical anatomy.

Maintaining qualification for 340B.

After initial acceptance in the 340B Drug Pricing Program, hospitals and health systems should monitor and take steps to maintain their disproportionate share hospital status to continue to qualify for participation. Proactively managing the Supplemental Security Income (SSI) Ratio will ensure the organization avoids an unexpected decline in the Medicare portion of its 340B patient base. Even with the surge resulting from Medicaid expansion, tracking patient eligibility for Medicare/ SSI to ensure all patients who qualify are appropriately enrolled in the program is an important step in maintaining 340B program eligibility.

Fast track to 340B.

Hospitals that are newly qualified for the 340B Drug Pricing Program may have an opportunity for fast-track approval to participate in the program. Three steps are required to seize this opportunity: Use data analytics to assess current and future percentages of Medicaid utilization and eligibility for federal SSI cash benefits. Determine the feasibility of early cost report filing. Prepare appropriate documentation and undertake the initial enrollment process.

PET-based compartmental modeling of (124)I-A33 antibody: quantitative characterization of patient-specific tumor targeting in colorectal cancer.

PURPOSE: The molecular specificity of monoclonal antibodies (mAbs) directed against tumor antigens has proven effective for targeted therapy of human cancers, as shown by a growing list of successful antibody-based drug products. We describe a novel, nonlinear compartmental model using PET-derived data to determine the "best-fit" parameters and model-derived quantities for optimizing biodistribution of intravenously injected (124)I-labeled antitumor antibodies. METHODS: As an example of this paradigm, quantitative image and kinetic analyses of anti-A33 humanized mAb (also known as "A33") were performed in 11 colorectal cancer patients. Serial whole-body PET scans of (124)I-labeled A33 and blood samples were acquired and the resulting tissue time-activity data for each patient were fit to a nonlinear compartmental model using the SAAM II computer code. RESULTS: Excellent agreement was observed between fitted and measured parameters of tumor uptake, "off-target" uptake in bowel mucosa, blood clearance, tumor antigen levels, and percent antigen occupancy. CONCLUSION: This approach should be generally applicable to antibody-antigen systems in human tumors for which the masses of antigen-expressing tumor and of normal tissues can be estimated and for which antibody kinetics can be measured with PET. Ultimately, based on each patient's resulting "best-fit" nonlinear model, a patient-specific optimum mAb dose (in micromoles, for example) may be derived.

Mechanical temporal fluctuation induced distance and force systematic errors in Casimir force experiments.

The basic theory of temporal mechanical fluctuation induced systematic errors in Casimir force experiments is developed and applications of this theory to several experiments is reviewed. This class of systematic error enters in a manner similar to the usual surface roughness correction, but unlike the treatment of surface roughness for which an exact result requires an electromagnetic mode analysis, time dependent fluctuations can be treated exactly, assuming the fluctuation times are much longer than the zero point and thermal fluctuation correlation times of the electromagnetic field between the plates. An experimental method for measuring absolute distance with high bandwidth is also described and measurement data presented.

Simultaneous resection for rectal cancer with synchronous liver metastasis is a safe procedure.

BACKGROUND: One quarter of colorectal cancer patients will present with liver metastasis at the time of diagnosis. Recent studies have shown that simultaneous resections are safe and feasible for stage IV colon cancer. Limited data are available for simultaneous surgery in stage IV rectal cancer patients. METHODS: One hundred ninety-eight patients underwent surgical treatment for stage IV rectal cancer. In 145 (73%) patients, a simultaneous procedure was performed. Fifty-three (27%) patients underwent staged liver resection. A subpopulation of 69 (35%) patients underwent major liver resection (3 segments or more) and 30 (44%) patients with simultaneous surgery. RESULTS: The demographics of the 2 groups were similar. Complication rates were comparable for simultaneous or staged resections, even in the group subjected to major liver resection. Total hospital stay was significantly shorter for the simultaneously resected patients (P < .01). CONCLUSIONS: Simultaneous resection of rectal primaries and liver metastases is a safe procedure in carefully selected patients at high-volume institutions, even if major liver resections are required.

Synergistic enhancement in the co-gelation of salt-soluble pea proteins and whey proteins.

This paper investigated the enhancement of thermal gelation properties when salt-soluble pea proteins were co-gelated with whey proteins in NaCl solutions, using different blend ratios, total protein concentrations, pH, and salt concentrations. Results showed that the thermal co-gelation of pea/whey proteins blended in ratio of 2:8 in NaCl solutions showed synergistic enhancement in storage modulus, gel hardness, paste viscosity and minimum gelation concentrations. The highest synergistic enhancement was observed at pH 6.0 as compared with pH 4.0 and 8.0, and at the lower total protein concentration of 10% as compared with 16% and 22% (w/v), as well as in lower NaCl concentrations of 0.5% and 1.0% as compared with 1.5%, 2.0%, 2.5%, and 3.0% (w/v). The least gelation concentrations were also lower in the different pea/whey protein blend ratios than in pure pea or whey proteins, when dissolved in 1.0% or 2.5% (w/v) NaCl aqueous solutions.

Hypofractionated stereotactic body radiotherapy in low-risk prostate adenocarcinoma: preliminary results of a multi-institutional phase 1 feasibility trial.

BACKGROUND: Recent reports using extreme hypofractionated regimens in the treatment of low-risk prostate adenocarcinoma have been encouraging. Here, the authors report on their own multi-institutional experience with extreme hypofractionated stereotactic radiotherapy for early stage disease. METHODS: In total, at 4 centers, 45 patients with National Comprehensive Cancer Network-defined, low-risk prostate adenocarcinoma were enrolled in a phase 1, multi-institutional trial of hypofractionated radiosurgery with a proprietary radiosurgical device (CyberKnife). Thirty-four patients received 7.5 grays (Gy) delivered in 5 fractions, 9 patients received 7.25 Gy delivered in 5 fractions, and 2 patients received other regimens. The variables evaluated were biochemical progression-free survival (bPFS), prostate-specific antigen (PSA) bounce, and toxicities. Health-related quality of life was evaluated using the Sexual Health Inventory for Men (SHIM), American Urological Association (AUA), and Expanded Prostate Cancer Index Composite (EPIC) questionnaires. RESULTS: The median follow-up for surviving patients was 44.5 months (range, 0-62 months). The bPFS rate at 3 years was 97.7%. The median PSA declined from 4.9 ng/mL at diagnosis to 0.2 ng/mL at last follow-up, and the median percentage PSA decline at 12 months was 80%. Nine patients experienced at least 1 PSA bounce ≥0.4 ng/mL, and 4 patients experienced 2 PSA bounces. The median time to first PSA bounce was 11.6 months (range, 7.2-18.2 months), and the mean percentage PSA bounce was 1.07 ng/mL. There was 1 episode of late grade 3 urinary obstruction, and there were 2 episodes of late grade 3 proctitis. There was a significant late decline in SHIM and EPIC sexual scores and a small, late decline in the EPIC Bowel domain score. CONCLUSIONS: In a select population, extreme hypofractionation with stereotactic radiosurgery was safe and effective for the treatment of low-risk prostate adenocarcinoma.

(124)I-huA33 antibody PET of colorectal cancer.

UNLABELLED: Humanized A33 (huA33) is a promising monoclonal antibody that recognizes A33 antigen, which is present in more than 95% of colorectal cancers and in normal bowel. In this study, we took advantage of quantitative PET to evaluate (124)I huA33 targeting, biodistribution, and safety in patients with colorectal cancer. We also determined the biodistribution of (124)I-huA33 when a large dose of human intravenous IgG (IVIG) was administered to manipulate the Fc receptor or when (124)I-huA33 was given via hepatic arterial infusion (HAI). METHODS: We studied 25 patients with primary or metastatic colorectal cancer; 19 patients had surgical exploration or resection. Patients received a median of 343 MBq (44.4-396 MBq) and 10 mg of (124)I-huA33. Nineteen patients received the antibody intravenously and 6 patients via HAI, and 5 patients also received IVIG. RESULTS: Ten of 12 primary tumors were visualized in 11 patients. The median concentration in primary colon tumors was 0.016% injected dose per gram, compared with 0.004% in normal colon. The PET-based median ratio of hepatic tumor uptake to normal-liver uptake was 3.9 (range, 1.8-22.2). Quantitation using PET, compared with well counting of serum and tissue, showed little difference. Prominent uptake in bowel hindered tumor identification in some patients. Pharmacokinetics showed that patients receiving IVIG had a significantly shorter serum half-time (41.6 ± 14.0 h) than those without (65.2 ± 9.8 h). There were no differences in clearance rates among the intravenous group, IVIG group, and HAI group, nor was there any difference in serum area under the curve, maximum serum concentration, or volume of distribution. Weak titers of human-antihuman antibodies were observed in 6 of 25 patients. No acute side effects or significant toxicities were associated with huA33. CONCLUSION: Good localization of (124)I-huA33 in colorectal cancer with no significant toxicity has been observed. PET-derived (124)I concentrations agreed well with those obtained by well counting of surgically resected tissue and blood, confirming the quantitative accuracy of (124)I-huA33 PET. The HAI route had no advantage over the intravenous route. No clinically significant changes in blood clearance were induced by IVIG.

Endoscopic management of complete colonic obstruction.

A patient with metastatic rectal cancer underwent a diverting transverse loop colostomy due to rectal obstruction. 16 months later, he underwent a low anterior resection to resect his rectal cancer along with reversal of his transverse colostomy, and creation of a temporary loop ileostomy. Six months later, he was brought to the operating room for closure of his ileostomy. Post-operatively, the patient developed nausea, vomiting, and abdominal distention and imaging revealed a large bowel obstruction, confirmed by colonoscopy. The patient refused surgical diversion and a cecostomy tube was placed for decompression. After maturation of the cecostomy fistula, a rendezvous colonoscopy was performed, retrograde through the rectum and antegrade through the cecostomy fistula. The obstructing mucosa was traversed and the site of obstruction was balloon dilated, relieving the obstruction endoscopically.

Noninvasive stereotactic radiosurgery (CyberHeart) for creation of ablation lesions in the atrium.

BACKGROUND: A variety of catheter-based energy modalities are used for cardiac ablation to treat arrhythmias. Robotic radiosurgery is increasingly being utilized to successfully accomplish precise tissue ablation in anatomically remote areas. OBJECTIVE: The purpose of this study was to examine the experimental feasibility of a noninvasive method using stereotactic robotic radiosurgery (SRS) to create cardiac lesions. METHODS: Sixteen (16) Hanford-Sinclair mini swine (weight 40-70 kg) under general anesthesia were studied. Baseline computed tomographic scans were performed, followed by electroanatomic mapping using the CARTO system. Stereotactic robotic radiosurgery was performed using the CyberHeart system, with predetermined targets at the cavotricuspid isthmus, AV node, pulmonary vein-left atrial junction, or left atrial appendage. From 25 to 196 days after treatment, the animals were investigated with repeat electroanatomic voltage mapping and transesophageal echocardiography, when possible. The animals then were sacrificed and pathology specimens taken. RESULTS: Dose ranging suggested that 25 Gy was needed to produce an electrophysiologic effect. The time course showed an electrophysiologic effect consistently by 90 days. The method was feasible for producing bidirectional cavotricuspid isthmus block and AV nodal conduction block. The pulmonary vein-left atrial junction and left atrial appendage showed marked voltage reduction to less than 0.05 mV. No spontaneous arrhythmias were observed. Pathology specimens showed no evidence of radiation damage outside the target. Histology samples from target sites showed effects consistent with X-beam radiation. CONCLUSION: Stereotactic robotic radiosurgery can produce cavotricuspid isthmus block, AV nodal block, and significant decreased voltage at the pulmonary vein-left atrial junction. No other organ damage was seen. The study findings demonstrate the feasibility of this noninvasive treatment method for creating cardiac lesions. This approach merits further investigation in the treatment of arrhythmias.

Ureteroileocecal appendicostomy based urinary reservoir in irradiated and nonirradiated patients.

PURPOSE: The ureteroileocecal appendicostomy reservoir is designed to potentially decrease the morbidity of continent diversion, particularly in previously irradiated patients. We report our experience with this reservoir to compare complications in irradiated and nonirradiated patients. MATERIALS AND METHODS: The records of 52 consecutive patients who underwent ureteroileocecal appendicostomy diversion between March 2001 and January 2008 were evaluated. Outcomes were analyzed according to whether patients received radiation therapy to the pelvis. Complications were reported as early (within 90 days of surgery) or late. RESULTS: Overall 29 patients received radiation therapy. The incidence of early complications requiring operative intervention was 14%, including 2 patients (9%) with and 5 (17%) without radiation (p = 0.68). All except 1 reoperation was done to revise the stoma. Early urinary tract infections developed in 17% of nonirradiated and 28% of irradiated patients (p = 0.51). The most common late complication was stomal stenosis requiring dilation on an outpatient basis, which occurred in 21% of patients, including 4 with (17%) and 7 without (24%) radiation (p = 0.74). Late ureteral complications requiring intervention were reported in 15% of renal units, including 2 of 44 without (5%) and 6 of 56 with (11%) radiation (p = 0.21). CONCLUSIONS: Ureteroileocecal appendicostomy is a safe, effective technique for continent cutaneous urinary diversion in heavily irradiated patients. Complication rates did not significantly differ between irradiated and nonirradiated patients, and appear improved compared to those in previous reports.

Prospective, randomized, multicenter Food and Drug Administration investigational device exemption study of lumbar total disc replacement with the CHARITE artificial disc versus lumbar fusion: five-year follow-up.

BACKGROUND CONTEXT: The CHARITE artificial disc, a lumbar spinal arthroplasty device, was approved by the United States Food and Drug Administration in 2004 based on two-year safety and effectiveness data from a multicenter, prospective, randomized investigational device exemption (IDE) study. No long-term, randomized, prospective study on the CHARITE disc or any other artificial disc has been published to date. PURPOSE: The purpose of this study was to compare the safety and effectiveness at the five-year follow-up time point of lumbar total disc replacement using the CHARITE artificial disc (DePuy Spine, Raynham, MA) with that of anterior lumbar interbody fusion (ALIF) with BAK cages and iliac crest autograft, for the treatment of single-level degenerative disc disease from L4 to S1, unresponsive to nonoperative treatment. STUDY DESIGN/SETTING: Randomized controlled trial-five-year follow-up. PATIENT SAMPLE: Ninety CHARITE patients and 43 BAK patients. OUTCOME MEASURES: Self-reported measures: visual analog scale (VAS); validated Oswestry disability index (ODI version 1.0); Short-Form 36 Questionnaire, and patient satisfaction. Physiologic measures: radiographic range of motion, disc height, and segmental translation. Functional measures: work status. METHODS: Of the 375 subjects enrolled in the CHARITE IDE trial, 277 were eligible for the five-year study and 160 patients thereof completed the five-year follow-up. The completers included 133 randomized patients. Overall success was defined as improvement> or =15 pts in ODI vs. baseline, no device failure, absence of major complications, and maintenance or improvement of neurological status. Additional clinical outcomes included an ODI questionnaire as well as VAS, SF-36, and patient satisfaction surveys. Work status was tracked for all patients. Safety assessments included occurrence and severity of adverse events and device failures. Radiographic analyses such as index- and adjacent-level range of motion, segmental translation, disc height, and longitudinal ossification were also carried out. RESULTS: Overall success was 57.8% in the CHARITE group vs. 51.2% in the BAK group (Blackwelder's test: p=0.0359, Delta=0.10). In addition, mean changes from baseline for ODI (CHARITE: -24.0 pts vs. BAK: -27.5 pts), VAS pain scores (CHARITE: -38.7 vs. BAK: -40.0), and SF-36 questionnaires (SF-36 Physical Component Scores [PCS]: CHARITE: 12.6 pts vs. BAK: 12.3 pts) were similar across groups. In patient satisfaction surveys, 78% of CHARITE patients were satisfied vs. 72% of BAK patients. A total of 65.6% patients in the CHARITE group vs. 46.5% patients in the BAK group were employed full-time. This difference was statistically significant (p=0.0403). Long-term disability was recorded for 8.0% of CHARITE patients and 20.9% of BAK patients, a difference that was also statistically significant (p=0.0441). Additional index-level surgery was performed in 7.7% of CHARITE patients and 16.3% of BAK patients. Radiographic findings included operative and adjacent-level range of motion (ROM), intervertebral disc height and segmental translation. At the five-year follow-up, the mean ROM at the index level was 6.0 degrees for CHARITE patients and 1.0 degrees for BAK patients. Changes in disc height were also similar for both CHARITE and BAK patients (0.7 mm for both groups, p=0.9827). Segmental translation was 0.4 and 0.8mm in patients implanted with CHARITE at L4-L5 vs. L5-S1, respectively, and 0.1mm in BAK patients. CONCLUSIONS: The results of this five-year, prospective, randomized multicenter study are consistent with the two-year reports of noninferiority of CHARITE artificial disc vs. ALIF with BAK and iliac crest autograft. No statistical differences were found in clinical outcomes between groups. In addition, CHARITE patients reached a statistically greater rate of part- and full-time employment and a statistically lower rate of long-term disability, compared with BAK patients. Radiographically, the ROMs at index- and adjacent levels were not statistically different from those observed at two-years postsurgery.

Use of an ureteroileocecal appendicostomy urinary reservoir in patients with recurrent pelvic malignancies treated with radiation.

OBJECTIVE: Evaluation of a modified right colon urinary reservoir in a heavily radiated patient population undergoing pelvic exenteration. METHODS: A retrospective chart review was performed on all patients with recurrent gynecologic, colorectal, and urological tumors who underwent total pelvic or anterior exenteration and urinary diversion from 3/01 to 7/03 using an ureteroileocecal appendicostomy urinary reservoir. RESULTS: Fourteen patients were identified over the study interval. The mean age of the patients was 53 years (range, 22-78 years). All patients received external beam, intracavitary, or a combination of both radiation treatment modalities to the pelvis preoperatively. Eight patients received intraoperative radiation therapy (IORT) at a mean dose of 16.25 Gy (range, 12.5-17.5 Gy). The primary sites of disease were as follows: cervix, five; prostate, three; uterus, two; colon/rectum two; and one each for vulva and bladder. Complete stomal continence was achieved in all patients after a median follow-up of 10 months (range, 2-31 months). Two patients experienced a traumatic disruption of the stomal-skin anastomosis in the early postoperative period (postoperative days 7 and 14). One late complication related to the ureterointestinal anastomosis was observed and consisted of an anastomotic stricture managed conservatively. One patient experienced an entero-pouch fistula following re-exploration for an acute postoperative hemorrhage. CONCLUSION: The early outcomes using the ureteroileocecal appendicostomy urinary reservoir in heavily radiated patients demonstrate the technical feasibility of this design as both minimal early stoma and ureterointestinal complications may occur. Longer postoperative follow-up will be required to address the late outcomes of this procedure and its ultimate use in this population.

Rate of pathologic complete response with increased interval between preoperative combined modality therapy and rectal cancer resection.

INTRODUCTION: Recent data suggest a favorable prognosis for rectal cancer patients with a pathologic complete response to preoperative combined modality therapy. Prolongation of the interval between preoperative combined modality therapy and surgery (RT-surgery interval) as a means of increasing pathologic complete response rate has not been fully examined. METHODS: One hundred and fifty-five rectal cancer patients undergoing preoperative pelvic external beam radiation therapy and 5-fluorouracil-based chemotherapy followed by rectal resection were identified. All patients had endorectal ultrasound prior to combined modality therapy. Final pathology reports were reviewed for ypT and ypN stage and margin status. Medical records were reviewed for sphincter preservation, operative time, estimated blood loss, hospital stay, and morbidity (overall, anastomotic, and perineal). RESULTS: A pathologic complete response (ypT0N0) occurred in 24 patients (15 percent). Median RT-surgery interval was 44 (range, 15-206) days. A pathologic complete response occurred in 19 percent of patients with an interval >44 days, vs. 12 percent in those with an interval < or =44 days ( P = 0.27). Downstaging by three stages occurred more frequently in the long-interval group (15 percent vs. 6 percent, P = 0.11). The rates of sphincter preservation, positive margins, estimated blood loss, and operative time were not significantly different. Overall morbidity was similar between groups. CONCLUSIONS: Our results demonstrate a trend toward increased pathologic complete response rate and downstaging with increased RT-surgery interval. However, sphincter preservation is not increased. Until prospective analyses are conducted assessing the impact of prolonged RT-surgery interval on long-term outcome, the benefit of a prolonged interval between the completion of preoperative combined modality therapy and surgery remains unclear.

Postcolumn HPLC detection of mono- and oligosaccharides with a chemosensor.

Novel chromophoric compound 1 promotes the HPLC postcolumn detection of mono- and oligosaccharides. The detection of chromatographic peaks in the visible region for glucose, fructose, maltodextrins, sialic acid, and a ganglioside can be accomplished with a standard UV-vis detector. The use of selective, reversible binding agents in automated HPLC assays should allow for improved monitoring of specific analytes as well as material recovery. [structure: see text]

Primary adenocarcinoma of the anus treated with combined modality therapy.

PURPOSE: The purpose of this study was to determine the local control and survival of patients with adenocarcinoma of the anus who received combined modality therapy as a component of their treatment. METHODS: Thirteen patients with primary anal adenocarcinoma (T1: 1, T2: 4, T3: 3, T4: 5; and N0: 9, N1: 2, N2: 2) were treated between 1989 and 2001 in the Department of Radiation Oncology at Memorial Sloan Kettering Cancer Center. Three general treatment approaches were used that were based on physician and patient preference as well as tumor stage. These included preoperative combined modality therapy followed by abdominoperineal resection (n = 5), with four of the five receiving postoperative chemotherapy; local excision followed by postoperative radiation alone or combined modality therapy (n = 5); and abdominoperineal resection followed by postoperative combined modality therapy (n = 3). Two patients received brachytherapy. RESULTS: With a median follow-up of 19 months, the median survival was 26 months, the local failure rate was 37 percent, and the two-year actuarial survival was 62 percent. In the subset of eight patients treated with abdominoperineal resection and preoperative or postoperative radiation or combined modality therapy, local control was 63 percent, and three of eight are without evidence of disease. Of the five patients who underwent a local excision followed by postoperative radiation or combined modality therapy, the local control rate was 60 percent, with one of the local failures salvaged by abdominoperineal resection and one of five patients without evidence of disease. CONCLUSION: Although the experience is limited, our data suggest that the combination of abdominoperineal resection and combined modality therapy is a reasonable approach for this rare tumor.

Evaluation of preoperative and postoperative radiotherapy on long-term functional results of straight coloanal anastomosis.

PURPOSE: Preoperative radiotherapy for rectal cancer avoids radiation to the reconstructed rectum and may circumvent the detrimental effects on bowel function associated with postoperative radiotherapy. We compared the long-term functional results of patients who received preoperative radiotherapy, postoperative radiotherapy, or no radiotherapy in conjunction with low anterior resection and coloanal anastomosis to assess the impact of pelvic radiation on anorectal function. METHODS: One hundred nine patients treated by low anterior resection and straight coloanal anastomosis for rectal cancer between 1986 and 1997 were assessed with a standardized questionnaire at two to eight years after resection. All radiotherapy was given to a total dose of 4,500 to 5,400 cGy with conventional doses and techniques. Most patients received concurrent 5-fluorouracil-based chemotherapy. RESULTS: There were 39 patients in the preoperative radiotherapy group, 11 patients in the postoperative radiotherapy group, and 59 patients in the no radiotherapy group. The postoperative radiotherapy group reported a significantly greater number of bowel movements per 24-hour period (P < 0.01) and significantly more episodes of clustered bowel movements (P < 0.02) than either the preoperative radiotherapy group or the no radiotherapy group. No significant difference in anal continence or satisfaction with bowel function was found among the three groups. CONCLUSION: In this study of straight (nonreservoir) coloanal anastomoses, postoperative pelvic radiotherapy had significant adverse effects on anorectal function, with higher rates of clustering and frequency of defecation than with preoperative radiotherapy. No differences in continence rates were demonstrated, perhaps because of the sample size of the compared groups. We attribute the adverse effects of postoperative radiotherapy to irradiation of the neorectum, which is spared when treatment is given preoperatively. The deleterious effects of adjuvant radiation on long-term anorectal function can be reduced by preoperative treatment.