Sensory and motor dysfunction assessed by anorectal manometry in uterine cervical carcinoma patients with radiation-induced late rectal complication

Nipple-areolar complex sensory recovery based on incision placement after nipple-sparing mastectomy: a prospective nonrandomized controlled trial

INTRODUCTION

Nipple-sparing mastectomy (NSM) aims to improve patient satisfaction by preserving the nipple-areola complex (NAC) while ensuring oncologic safety. Different surgical incisions, such as inframammary fold (IMF) and periareolar/radial incisions, are used in NSM; however, their impact on NAC sensory loss remains unclear. In this study, the authors aimed to assess NAC sensation after NSM and compare the results of different incisional approaches, specifically IMF versus periareolar/radial.

METHODS

In this prospective, single-center, nonrandomized controlled trial, 105 post-NSM patients were recruited from October 2019 to November 2021 and followed up at 24-48 months postsurgery. Of these, 97 (IMF: 65; periareolar/radial: 32) were analyzed for sensory assessment. NAC sensation was measured using the pin-prick test, with scores ranging from 0 (no sensation) to 2 (sharp sensation) across five NAC areas. Sensory loss was defined as a total score below 3.

RESULTS

The median total score on the pin-prick test for NAC sensation was significantly higher in the IMF incision group than in the periareolar/radial incision group (3.77±3.11 vs. 2.47±2.51; P=0.043). The rate of NAC sensory loss was significantly lower in the IMF group than in the periareolar/radial group (36.9% vs. 62.5%; P=0.017). Multivariable analysis revealed that the incisional approach (95% CI: 0.14-0.97; P=0.044) and radiotherapy (95% CI: 0.05-0.36; P<0.01) were independent determinants of NAC sensory loss.

CONCLUSION

Our study emphasized the importance of incision placement during NSM in preserving NAC sensation and may provide a valuable perspective for clinicians and patients considering this surgical approach.

Can Anorectal Manometry Findings Predict Subsequent Late Gastrointestinal Radiation Toxicity in Prostate Cancer Patients?

PURPOSE

The purpose of this study is to investigate the influence of radiotherapy (RT) on anorectal function and radiation-induced toxicity in patients with prostate cancer.

MATERIALS AND METHODS

Fifty-four patients who were treated with RT for prostate cancer (T1c-4N0-1M0) were evaluated. To assess the changes in anorectal function, two consecutive anorectal manometry readings were performed in patients, before and after 4-6 months of RT. Late gastrointestinal (GI) toxicity was defined as symptoms occurring more than 6 months after RT. The median radiation dose was 70.0 Gy (range, 66.0 to 74.0 Gy). Whole pelvis field RT was performed in 16 patients (29.6%). Grade of late radiation toxicity was defined in accordance to the severity of symptoms (Gulliford's scoring system).

RESULTS

The median follow-up period was 60 months. Resting anal pressure (p=0.001), squeeze pressure (p < 0.001), and urge to defecate volume (p=0.025) were significantly reduced after RT. Fourteen patients (25.9%) experienced late GI toxicities. Among them, nine (16.7%) showed severe (grade ≥ 2) late toxicities. Elevated resting and squeeze external anal sphincter pressure prior to RT and large urge to defecate volumes after RT were associated with the occurrence of late GI toxicities.

CONCLUSION

RT caused symptomatic anorectal dysfunction and resulted in a weakened anal sphincter. Increased urge to defecate volumes after RT were related to late GI toxicities. Elevated resting and squeeze anal sphincter pressure prior to RT rodcan be used to identify patients with an increased risk of late GI toxicities.

Systematic review: anal and rectal changes after radiotherapy for prostate cancer

PURPOSE

Pelvic radiotherapy may lead to changes of anorectal function resulting in incontinence-related complaints. The aim of this study was to systematically review objective findings of late anorectal physiology and mucosal appearance after irradiation for prostate cancer.

METHODS

MEDLINE, EMBASE, and the Cochrane library were searched. Original articles in which anal function, rectal function, or rectal mucosa were examined ≥3 months after EBRT for prostate cancer were included.

RESULTS

Twenty-one studies were included with low to moderate quality. Anal resting pressures significantly decreased in 6 of the 9 studies including 277 patients. Changes of squeeze pressure and rectoanal inhibitory reflex were less uniform. Rectal distensibility was significantly impaired after EBRT in 7 of 9 studies (277 patients). In 4 of 9 studies on anal and in 5 of 9 on rectal function, disturbances were associated with urgency, frequent bowel movements or fecal incontinence. Mucosal changes as assessed by the Vienna Rectoscopy Score revealed telangiectasias in 73 %, congestion in 33 %, and ulceration in 4 % of patients in 8 studies including 346 patients, but no strictures or necrosis. Three studies reported mucosal improvement during follow-up. Telangiectasias, particularly multiple, were associated with rectal bleeding. Not all bowel complaints (30 %) were related to radiotherapy.

CONCLUSIONS

Low to moderate quality evidence indicates that EBRT reduces anal resting pressure, decreases rectal distensibility, and frequently induces telangiectasias of rectal mucosa. Objective changes may be associated with fecal incontinence, urgency, frequent bowel movements, and rectal bleeding, but these symptoms are not always related to radiation damage.

Faecal incontinence in male patients

OBJECTIVE

Data concerning faecal incontinence (FI) in men are lacking. The aim of this study was to evaluate the historical aetiology and contrast aetiologies in younger and older men suffering from FI.

METHOD

After institutional review board approval, a retrospective chart review was undertaken of all patients with FI seen between 1999 and 2005. The data of male patients was further analysed to assess the impact of age and historical aetiology on FI.

RESULTS

A total of 404 males were included, 203 patients were <70 years of age (group A) and 201 patients were >or=70 years of age (group B). The most common prior diagnosis in group A was perianal sepsis in 23 (11.3%) patients and symptomatic haemorrhoids in 20 (9.9%) patients; in group B it was prostate cancer in 57 (28.4%) patients, symptomatic haemorrhoids in 31 (15.4%) patients and neurological diseases in 18 (9%) patients. The most common prior procedure in group A was restorative proctectomy/proctocolectomy in 32 (15.8%) patients, fistulotomy or haemorrhoidectomy in 21 (10.3%) and 19 (9.4%) patients respectively. In group B, radiation therapy for prostate cancer was utilized in 48 (23.9%) patients and haemorrhoidectomy in 29 (14.4%) patients. Comparing group A and group B relative to diagnosis - perianal sepsis, perineal trauma, congenital disorders, HIV infection and anal cancer were more common in group A, whereas prostate cancer, neurological diseases and colon cancer were significantly more common in group B.

CONCLUSION

Prostate cancer, symptomatic haemorrhoids, perianal sepsis, rectal cancer and a history of restorative rectal resection were common associations with FI in men. The aetiologies for FI in men vary with age.

Preoperative chemoradiation for rectal cancer causes prolonged pudendal nerve terminal motor latency

PURPOSE

A worsened anorectal function after chemoradiation for high-risk rectal cancer is often attributed to radiation damage of the anorectum and pelvic floor. Its impact on pudendal nerve function is unclear. This prospective study evaluated the short-term effect of preoperative combined chemoradiation on anorectal physiologic and pudendal nerve function.

METHODS

Sixty-six patients (39 men, 27 women) with localized resectable (T3, T4, or N1) rectal cancer were included in the study. All patients received 45 Gy (1.8 Gy/day in 25 fractions) over five weeks, plus 5-fluorouracil (350 mg/m2/day) and leucovorin (20 mg/m2/day) concurrently on days 1 to 5 and 29 to 33. Patients who had rectal cancer with a distal margin within 6 cm of the anal verge had the anus included in the field of radiotherapy (Group A, n = 26). Patients who had rectal cancer with a distal margin 6 to 12 cm from the anal verge had shielding of the anus during radiotherapy (Group B, n = 40). The Wexner continence score, anorectal manometry and pudendal nerve terminal motor latency were assessed at baseline and four weeks after completion of chemoradiation.

RESULTS

The median Wexner score deteriorated significantly (P < 0.0001) from 0 to 2.5 for both Groups A (range, 0-8) and B (range, 0-14). The maximum resting anal pressures were unchanged after chemoradiation. The maximum squeeze anal pressures were reduced (mean = 166.5-157.5 mmHg) after chemoradiation. This change was similar in both Groups A and B. Eighteen patients (Group A = 7, Group B = 11) developed prolonged pudendal nerve terminal motor latency after chemoradiation. These 18 patients similarly had a worsened median Wexner continence score (range, 0-3) and maximum squeeze anal pressures (mean = 165.5-144 mmHg). The results obtained were independent of tumor response to chemoradiation.

CONCLUSIONS

Preoperative chemoradiation for rectal cancer carries a significant risk of pudendal neuropathy, which might contribute to the incidence of fecal incontinence after restorative proctectomy for rectal cancer.

Faecal incontinence: A late side-effect of pelvic radiotherapy

AIMS

Despite advances in pelvic radiotherapy, damage to normal tissue can lead to chronic gastrointestinal problems. The frequency with which this affects quality of life is controversial. Faecal incontinence is not widely perceived to be a major issue after pelvic radiotherapy. The aim of this paper is to review the frequency and mechanisms for the development of faecal incontinence after pelvic radiotherapy, and to review treatment options for faecally incontinent patients.

MATERIALS AND METHODS

A search of original literature was carried out using MEDLINE and EMBASE databases from 1966 to 2005.

RESULTS

The reliability of the published data is poor because patients frequently fail to admit to faecal incontinence, and because prospective studies are lacking that assess faecal incontinence as a specific end point using adequate, validated and reproducible methodology. The published rates of late new-onset faecal incontinence after pelvic radiation are between 3% and 53%. Patients treated for prostate rather than gynaecological, bladder, rectal or anal cancer may have a lower rate. Only 8-56% of affected patients state that faecal incontinence reduces their quality of life. Studies examining the physiological changes occurring after radiotherapy are generally not adequately controlled or powered, assessment of ano-rectal function is rarely comprehensive and loss of patients to follow-up frequently makes it difficult to extrapolate results to a wider population. Where there is agreement over the physiological changes that occur after radiotherapy, it is not clear at what threshold these changes cause symptoms. No prospective studies of any non-surgical treatment for faecal incontinence after radiotherapy have been published. Surgery other than colostomy probably carries a high risk of complications in this group of patients, but few data have been published.

CONCLUSIONS

Now that improvements in outcome from combination treatments, including radiotherapy for pelvic cancer, are being achieved, it is time that serious attention is paid to determining how frequently significant gastrointestinal toxicity arises, and how best to optimise the quality of life of long-term survivors.

Prospective comparison of short- and long-term effects of pelvic floor exercise/biofeedback training in patients with fecal incontinence after surgery plus irradiation versus surgery alone for colorectal cancer: clinical, functional and endoscopic/endosonographic findings

OBJECTIVE

The influence of irradiation on the clinical severity of incontinence, sphincter function, morphologic features and short/long-term treatment effects of sphincter training therapy is still insufficiently understood in irradiated patients with fecal incontinence after surgery for colorectal cancer. These parameters were compared in irradiated and non-irradiated patients and followed prospectively with regard to short- and long-term training effects.

MATERIAL AND METHODS

Forty-one patients having been irradiated after surgery (50.0+/-5.0 Gy) and 54 non-irradiated patients with fecal incontinence participated in this prospective, non-randomized trial. Baseline evaluation included a semiquantitative severity assessment score of fecal incontinence (modified Cleveland Incontinence Score (MCIS)), rectal manometry and endoscopy. After 3 weeks (short term) of intensive in-hospital pelvic floor exercise combined with biofeedback training, a second evaluation was made. In addition, anal endosonography (EUS) was performed in cases of treatment failure. After one year (long term) a third evaluation was made clinically (MCIS score).

RESULTS

Irradiated patients presented with a significantly higher degree of fecal incontinence (lower MCIS) compared to non-irradiated patients: 7.4+/-2.2 versus 8.7+/-2.7 points (p<0.001). Rectosigmoidal inflammation was more frequent in irradiated than non-irradiated patients (26.9% versus 9.3%) (p<0.03). Sphincter pressure, sensation/pain threshold and the rectoanal inhibitory reflex were similar in both groups. A significant short-term training effect was observed in both groups following sphincter training therapy in terms of an increase in MCIS from 7.4+/-2.2 to 9.4+/-2.7 points in the irradiated group and from 8.7+/-2.7 to 11.4+/-2.5 points in the non-irradiated group (p<0.0001). After one year the scores were 8.2+/-3.8 and 10.7+/-4.4 points, respectively (p<0.0001). There was a significant correlation (p<0.001) between baseline MCIS and the short- and long-term MCIS. In patients with short-term treatment failure (16.6%) anal EUS revealed structural defects of the external sphincter in four patients. There was no association of sphincter diameter with sphincter pressure, sensation/pain threshold and short/long-term MCIS.

CONCLUSIONS

The main result of this study is that irradiated patients show short- and long-term training effects comparable with those of non-irradiated patients despite the higher degree of incontinence at baseline. The correlation between the initial MCIS and short- and long-term treatment effects may be regarded as an important clinical predictor for treatment outcome. Functional and morphologic features are less suitable for this purpose.

Gastrointestinal symptoms after pelvic radiotherapy: role for the gastroenterologist?

PURPOSE

To analyze the cause of GI symptoms after pelvic radiotherapy (RT) in a consecutive series of patients with symptoms beginning after RT. A striking lack of evidence is available concerning the optimal treatment for the 50% of patients who develop permanent changes in bowel habits affecting their quality of life after pelvic RT. As a result, in the UK, most such patients are never referred to a gastroenterologist.

METHODS AND MATERIALS

All diagnoses were prospectively recorded from a consecutive series of patients with symptoms that started after RT and who were referred during a 32-month period to a gastroenterology clinic. Patients either underwent direct access flexible sigmoidoscopy or were investigated in a standard manner by one gastroenterologist after first being seen in the clinic.

RESULTS

A total of 265 patients referred from 15 institutions were investigated. They included 90 women (median age, 61.5 years; range, 22-84 years) and 175 men (median age, 70 years; range, 31-85 years). RT had been completed a median of 3 years (range, 0.1-34 years) before the study in the women and 2 years (range, 0-21 years) before in the men. Of the 265 patients, 171 had primary urologic, 78 gynecologic, and 16 GI tumors. The GI symptoms included rectal bleeding in 171, urgency in 82, frequency in 80, tenesmus, discomfort, or pain in 79, fecal incontinence in 79, change in bowel habit in 42, weight loss in 19, vomiting without other obstructive symptoms in 18, steatorrhea in 7, nocturnal defecation in 8, obstructive symptoms in 4, and other in 24. After investigation, significant neoplasia was found in 12%. One-third of all diagnoses were unrelated to the previous RT. More than one-half of the patients had at least two diagnoses. Many of the abnormalities diagnosed were readily treatable. The symptoms were generally unhelpful in predicting the diagnosis, with the exception of pain, which was associated with neoplasia (p < 0.001).

CONCLUSION

The results of our study have shown that radiation enteritis is not a single disease entity. More than one-half of the patients had more than one GI diagnosis contributing to their symptoms. After pelvic RT, specific GI symptoms were not a reliable measure of the underlying diagnoses, and the evaluation of new GI symptoms is worthwhile. An algorithm for this purpose is proposed.

Long-term anorectal dysfunction after postoperative radiotherapy for rectal cancer

PURPOSE

Adjuvant radiotherapy in the treatment of rectal cancer has been shown to increase long-term morbidity causing severe anorectal dysfunction with physiologic changes whose interaction remains poorly understood. This study examines long-term anorectal morbidity from adjuvant postoperative radiotherapy.

METHODS

In a prospective study, patients with Dukes B or C rectal carcinoma were randomized to postoperative radiotherapy or no adjuvant treatment after anterior resection. The long-term effect of radiotherapy on anorectal function in a subset of surviving patients was assessed from a questionnaire on subjective symptoms and from physiology laboratory evaluation and flexible sigmoidoscopy.

RESULTS

Twelve of 15 patients (80 percent) treated with radiotherapy had increased bowel frequency compared with 3 of the 13 patients (23 percent) who did not have radiation therapy (P = 0.003). The former group had loose or liquid stool more often (60 vs. 23 percent, P = 0.05), had fecal incontinence more often (60 vs. 8 percent, P = 0.004), and wore pad more often (47 vs. 0 percent, P = 0.004). They also experienced fecal urgency and were unable to differentiate stool from gas more often. Endoscopy revealed a pale and atrophied mucosa and telangiectasias in the irradiated patients. Anorectal physiology showed a reduced rectal capacity (146 vs. 215 ml, P = 0.03) and maximum squeeze pressure (59 vs. 93 cm H2O, P = 0.003) in the radiotherapy group. Impedance planimetry demonstrated a reduced rectal distensibility in these patients (P < 0.0001).

CONCLUSIONS

Adjuvant postoperative radiotherapy after anterior resection causes severe long-term anorectal dysfunction, which is mainly the result of a weakened, less sensitive anal sphincter and an undistensible rectum with reduced capacity.

Topical phenylephrine in the treatment of radiation-induced faecal incontinence

AIMS

Acute bowel toxicity after pelvic radiotherapy is defined as occurring within 3 months of the start of treatment; chronic gastrointestinal toxicity may continue after the acute phase or start after a latent period. One in five patients develop chronic faecal incontinence affecting quality of life; how best to treat these patients is not known. This retrospective study aimed to determine the effects of a new agent, phenylephrine gel, in the treatment of chronic radiation-induced faecal incontinence.

MATERIALS AND METHODS

Patients prescribed phenylephrine gel for new-onset faecal incontinence after radiotherapy were identified from our database of patients treated in a specialist radiation-induced bowel damage clinic since 2000. Changes in the level of faecal incontinence were assessed using the Vaizey faecal incontinence scoring system before and after treatment.

RESULTS

Fifteen patients (nine men and six women) of mean age 70.5 years (standard deviation 8.2, age range 56-82 years) were treated with phenylephrine gel a median of 43 months after completing radiotherapy. The median Vaizey score before treatment with phenylephrine gel was 17 (interquartile range [IQR] 14-20) and after treatment was 14 (IQR 11-18) (P = 0.005). The median length of treatment with phenylephrine gel was 28 days (IQR 28-365). Scores improved in 11 out of 15 patients; four out of 15 patients showed substantial improvements of 7 or more points; and seven patients considered the gel helpful.

CONCLUSION

Topical phenylephrine gel for the treatment of radiation-induced faecal incontinence has not been previously reported. This small, retrospective study suggests that it may help most patients and, in some, the improvement may be substantial. However, larger placebo-controlled prospective studies are required.

Retrospective analysis of results of p(65)+Be neutron therapy for treatment of prostate adenocarcinoma at the cyclotron of Louvain-la-Leuve. Part II: Side effects and their influence on quality of life measured with QLQ-C30 of EORTC

PURPOSE

Between 1978 and 1998, 533 prostate adenocarcinoma patients were treated with mixed photon-neutron radiotherapy. We report on a retrospective series of patients for whom the side effects of the treatment and their impact on quality of life were assessed by a mailed questionnaire.

METHODS AND MATERIALS

The European Organization for Research and Treatment of Cancer quality-of-life core questionnaire and a prostate-specific questionnaire were used. Between 1990 and 1996, 308 consecutive patients were treated. Two protocols were used: pelvic fields (50 Gy equivalent photons, 2 Gy/fraction) followed by a prostate boost (66 Gy) or prostate alone. The neutron/photon ratio varied. The questionnaire was mailed to 262 patients presumed to be alive.

RESULTS

Of the 262 patients, 230 replied. Of the 230 patients, 73% had no trouble doing strenuous activities and 4% had trouble with taking a short walk. The overall physical condition and quality-of-life questions received a mean score of 5.2 and 5.3 on a 7-point scale, respectively. Twenty-two percent had bowel movements at least four times daily, and 6% did so six times or more. Retaining stool was a problem in 26%, and only 38% reported full continence; 17% urinated four times or more nightly. Urinary incontinence was scored as "quite a bit" or "very much" in 11% and 5%, respectively. Hematuria and dysuria (pain) were reported by 7% and 16%, respectively, mainly as moderate. Only 28% reported easy erections, but 75% judged the sexual change acceptable. A greater neutron/photon ratio was significantly associated with more bowel problems (p = 0.003).

CONCLUSION

Mixed photon-neutron therapy for prostate cancer was associated with significant patient-reported side effects. Their significant effect on patients' quality of life is described.

Rectal resection with low anastomosis: functional outcome

OBJECTIVE

Function after anterior, low anterior and intersphincteric resection for rectal cancer was studied.

METHOD

Of 139 patients 122 responded to a standardized questionnaire (Cleveland Clinic Continence Score) 108 +/- 46 weeks postoperatively and 70 underwent anorectal manometry at 26 +/- 15 weeks.

RESULTS

The postoperative continence score was dependent on the procedure (anterior resection 4.1 +/- 4.6, low anterior resection 6.9 +/- 5.6, intersphincteric resection 11.5 +/- 5.2; P < 0.0001). It was poorer after radiochemotherapy (9.0 vs. 5.7; P = 0.030), but after colonic pouch reconstruction there was no significant difference between low anterior resection (5.6 vs. 7.3) and intersphincteric resection (10.0 vs. 12.5). Mean and maximal resting pressures were significantly reduced after intersphincteric resection (24 +/- 9 and 40 +/- 13 mmHg, respectively, P < 0.001) and further reduced by radiochemotherapy. Squeeze pressure was unaffected by the operative procedures and radiochemotherapy. Maximum tolerable volume and rectal compliance were reduced, after both low anterior and intersphincteric resection. Statistical correlation between continence score and maximal resting pressure (P = 0.014), mean resting pressure (P = 0.002), urge volume (P = 0.037), and neorectal compliance (P = 0.0018) reached significance. Satisfaction with the functional outcome was expressed by 71% of patients.

CONCLUSION

After rectal resection the degree of impaired continence depended on the operative procedure and the form of reestablishment of intestinal continuity. Radiochemotherapy affected the outcome adversely. Despite reduced function, overall patient satisfaction was high.

Anorectal dysfunction after surgical treatment for cervical cancer

BACKGROUND

Although bowel symptoms and complaints are common after radical hysterectomy, the effects of operation on anorectal function are incompletely understood. In this prospective pilot study we evaluated the incidence of bowel symptoms, changes in anorectal physiology, and quality of life after radical hysterectomy.

STUDY DESIGN

Eleven women undergoing radical hysterectomy for early-stage cervical cancer completed bowel function symptom surveys and cancer-specific quality-of-life scales before operation and at 6 weeks and 6 months after operation. The bowel function symptom survey was also repeated at 18 months postoperation. Anorectal manometry, balloon defecation, and pudendal nerve latency tests were performed before the operation and 6 months postoperatively.

RESULTS

The mean age was 45.3 years (range 34 to 56 years), and four of the patients were postmenopausal. Resting and squeeze sphincter pressures, volume of saline infused at first leak, total volume retained, and threshold volume for maximum tolerable volume were all decreased significantly (p < 0.05) after operation. Pudendal nerve terminal motor latency increased (p < 0.05) bilaterally. There were no significant differences in sensory thresholds. At 18 months, two women reported constipation, six reported flatus incontinence, and two reported fecal incontinence. The total quality-of-life score declined at 6 weeks but then improved significantly by 6 months (p = 0.02).

CONCLUSIONS

Bowel dysfunction is common after radical hysterectomy. Many women exhibit manometric and subjective changes compatible with fecal incontinence.

Prospective evaluation of anorectal function after total mesorectal excision for rectal carcinoma with or without preoperative radiotherapy

OBJECTIVE

Anorectal function is greatly disturbed after rectal surgery with or without radiotherapy (RT). To clarify the underlying mechanisms, we designed a prospective study to evaluate the effect of RT and surgery on anorectal function and clinical outcome of patients with a rectal carcinoma.

METHODS

Thirty-four patients with a rectal carcinoma participated in this study. They filled out a symptom questionnaire and underwent anal manometry, anal and rectal mucosal electrosensitivity testing, and a rectal barostat, before surgery, 4 and 12 months postoperatively. Thirteen patients were lost to follow-up, 14 underwent surgery alone (total mesorectal excision [TME]), and seven also received RT (RT + TME).

RESULTS

Functional outcome was disappointing in both groups, with at 4 months a significantly higher defecation frequency after RT + TME as compared with TME. Anal sphincter function and rectal sensitivity to pressure-controlled distention were not affected by either treatment. Rectal compliance, however, was significantly reduced after RT + TME at 4 and 1 2 months, resulting in lower rectal volumes at the thresholds for first sensation and desire to defecate. Rectal but not anal mucosal electrosensitivity was higher after TME + RT.

CONCLUSIONS

Anorectal function after rectal surgery with or without RT is greatly hampered because of a decreased rectal compliance. After 12 months, partial improvement is shown, especially in the absence of RT.

Effects of radiation damage on intestinal morphology

The current flow of papers on intestinal structure, radiation science, and intestinal radiation response is reflected in the contents of this review. Multiparameter findings and changes in compartments, cells, or subcellular structure all contribute to the overall profile of the response. The well-recognized changes in proliferation, vessels, and fibrogenesis are accompanied by alterations in other compartments, such as neuroendocrine or immune components of the intestinal wall. The responses at the molecular level, such as in levels of hormones, cytokines, or neurotransmitters, are of fundamental importance. The intestine responds to localized radiation, or to changes in other organs that influence its structure or function: some structural parameters respond differently to different radiation schedules. Apart from radiation conditions, factors affecting the outcome include the pathophysiology of the irradiated subject and accompanying treatment or intervention. More progress in understanding the overall responses is expected in the next few years.

Radiation damage to the rectum and anus: pathophysiology, clinical features and surgical implications

Radiation kills cancer cells by inducing various degrees of deoxyribonucleic acid fragmentation and disruption of intracellular membranes that lead to either immediate or delayed cell death. Although radiation can be effective in destroying cancer, its usefulness is limited by damage to normal tissues that surround the target tumour or those in the path of the radiation beam. The rectum and anus are damaged frequently during radiotherapy for abdominopelvic malignancy, including preresection therapy for rectal cancer. Such damage is often associated with lesions in the perineal skin, genitourinary tract, colon, and small intestine. Surgical intervention often is required for the most severe forms of these complications.

Anorectal irradiation in pelvic radiotherapy: an assessment using in-vivo dosimetry

The objectives of this study were to measure by in-vivo techniques the radiation doses received by the anorectum during pelvic radiotherapy and compare these with doses predicted by a GE TARGET treatment planning system. Nine patients with cancers of the prostate, bladder, cervix or uterus were planned with computed tomography (CT) using the TARGET system. A Scanditronix rectal probe containing five n-type photon-detecting diodes was placed in the anorectum during the planning CT scans. The probe position was standardized with the five diodes at 2 cm intervals from the anal verge. The probe diodes were calibrated for 10 MV photons. Doses were measured for each diode for two consecutive fractions in the first four patients and for five consecutive fractions in the remaining five. Thermoluminescent dosimeters were used initially to verify diode doses. The TARGET and diode measured doses were compared. In all patients diodes situated in the target volume were within 7% of predicted doses. This improved to 2.5% after measurement on five fractions. At the edges of the target volume, wide variability existed between measured and predicted doses (measured dose range -68% to +68% of predicted dose). Outside the target volume, considerable doses (up to 0.3 Gy per fraction) were measured in the anal canal, which were not predicted by TARGET. We conclude that TARGET planned doses are accurate within the confines of the target volume. The greatest variability was seen at the edges of the target volume, where dose can vary by 50% across a 1 cm distance in the anterior-posterior plane. TARGET does not account for scattered dose beyond the field edges and therefore underestimates the dose received by the anal canal.

Anorectal injury following pelvic radiotherapy

BACKGROUND

Current knowledge of the effects of radiation on the anorectum is based on a limited number of studies. Variability in delivery techniques, both currently and historically, combined with a paucity of prospective and randomized studies makes interpretation of the literature difficult. This review presents the existing evidence and identifies areas that require further work.

METHODS

This review is based on a literature search (Medline and PubMed) and manual cross-referencing.

RESULTS AND CONCLUSION

More than three-quarters of patients receiving pelvic radiotherapy experience acute anorectal symptoms and up to one-fifth suffer from late-phase radiation proctitis. About 5 per cent develop other chronic complications, such as fistula, stricture and disabling faecal incontinence. The risk of rectal cancer may be increased. Conservative treatment options are of limited value. Surgery may be considered if symptoms are severe, provided sphincter function is adequate and recurrent disease is excluded. Large prospective studies with accurate dosimetric data and long-term follow-up are needed to provide meaningful information on which to base new strategies to minimize the side-effects from radiotherapy.