Misleading Presentation of Colorectal Cancer in an Otherwise Healthy Patient

Background: Colorectal cancer (CRC) represents the second most common malignancy and the fourth most common cause of cancer deaths. CRC can manifest early with bright red bleeding per rectum, tenesmus, and altered bowel habits. These symptoms are often attributed to benign lesions, including anal fissure. Our objective is to highlight the alarming scenario of an anal fissure masking the clinical features of an underlying colorectal cancer in healthy middle-aged patients. Case Report Our case report aims to discuss how congruent clinical features of benign-looking anal fissure can delay the diagnosis of rectal cancer. In January 2019, a healthy forty-four years old Iraqi male with no family history of colorectal neoplasms presented to Baghdad Medical City. He suffered from a long-standing peri-anal pain and infrequent bowel motion that was initially diagnosed as an anal fissure. Subsequent clinical assessment, with endoscopy, confirmed the presence of colorectal adenocarcinoma. We also carried out analytics, using Google Trends, to assess the spatiotemporal mapping of web users interested in case scenarios similar to our patient. Conclusion Anal fissure could coexist with colorectal cancer, even in younger patients. Therefore, it is essential to consider anal fissure and colorectal cancer on clinical assessment. Follow-up visits are paramount to exclude underlying life-threatening aetiology at secondary care.

A feasibility study of hyoscine butylbromide (buscopan) to improve image quality of cone beam computed tomography during abdominal/pelvic Stereotactic Ablative Radiotherapy

Objectives: Cone beam computed tomography (CBCT) is used for image guidance of stereotactic ablative radiotherapy (SABR), but it is susceptible to bowel motion artefacts. This trial evaluated the impact of hyoscine butylbromide (buscopan) on CBCT image quality and its feasibility within a radiotherapy workflow. Methods: A single-centre feasibility trial (ISRCTN24362767) was performed in patients treated with SABR for abdominal/pelvic oligorecurrence. Buscopan was administered to separate cohorts by intramuscular (IM) or intravenous (i.v.) injection on alternate fractions, providing within-patient control data. 4-point Likert scales were used to assess overall image quality (ranging from excellent to impossible to use) and bowel motion artefact (ranging from none to severe). Feasibility was determined by patient/radiographer questionnaires and toxicity assessment. Descriptive statistics are presented. Results: 16 patients were treated (8 by IM and 8 by i.v. buscopan). The percentage of images of excellent quality with/without buscopan was 47 vs 29% for IM buscopan and 65 vs 40% for i.v. buscopan. The percentage of images with no bowel motion artefact with/without buscopan was 24.6 vs 8.9% for IM buscopan and 25.8 vs 7% for i.v. buscopan. Four patients (25%) reported dry mouth. 14 patients (93%) would accept buscopan as routine. 11 radiographers (92%) reported no delay in treatments. Conclusions: A trend towards improved image quality/reduced bowel motion artefact was observed with IM/i.v. buscopan. Buscopan was well tolerated with limited impact on workflow. Advances in knowledge: This is the first trial of buscopan within a radiotherapy workflow. It demonstrated a trend to improved image quality and feasibility of use.

Evaluation of Small Bowel Motion and Feasibility of using the Peritoneal Space to Replace Bowel Loops for Dose Constraints during Intensity-Modulated Radiotherapy for Rectal Cancer

Background The goal of this study was to assess small bowel motion and explore the feasibility of using peritoneal space (PS) to replace bowel loops (BL) via the dose constraint method to spare the small bowel during intensity-modulated radiotherapy (IMRT) for rectal cancer. Methods A total of 24 patients with rectal cancer who underwent adjuvant radiotherapy were selected. Weekly repeat CT scans from pre-treatment to the fourth week of treatment were acquired and defined as Plan, 1W, 2W, 3W, and 4W. BL and PS contours were delineated in all of the scans. Two IMRT plans called P PS and P BL were designed on Plan CT using two dose PS and BL constraint methods, respectively, and then copied to CT 1~4W. The shift%, dose volume, and NTCP of the small bowel in P PS and P BL during treatment were evaluated. Results Overall, 109 sets of CT scans from 24 patients were acquired, and 218 plans were designed and copied. The PS and BL volumes were 1339.28 cc and 250.27 cc. The BL and PS shift% V 15 was 28.48% and 11.79% ( p =0.000), which was less in the prone position than in the supine position (25.24% vs 32.10%, p =0.000; 9.9% vs 14.85%, p =0.000). On all of the CT scans, most P PS small bowel dose volumes were less than from P BL . V 15 was 170.07 cc vs 178.58 cc ( p =0.000), and they had a significant correlation. The NTCP of chronic and acute side effects from P PS was significantly less than P BL (2.80% vs 3.00%, p =0.018; 57.32% vs 58.64%, p =0.000). Conclusions This study indicated that small bowel motion may lead to uncertainties in its dose volume and NTCP evaluation during IMRT for rectal cancer. The BL movements were significantly greater than PS, and the prone position was significantly less than the supine position. Using PS instead of BL can spare the small bowel. V 15 <830 cc is the dose constraint standard.

Assessment of bowel motion in patients receiving pelvic Stereotactic ablative radiotherapy (SABR)

Poster presented at BAPIO National Conference, London 2019 Peer reviewed by Subarna Chakravorty PhD & Sunil Daga PhD

Evaluation of Small Bowel Motion and Feasibility of using the Peritoneal Space to Replace Bowel Loops for Dose Constraints during Intensity-Modulated Radiotherapy for Rectal Cancer

Background: The goal of this study was to assess small bowel motion and explore the feasibility of using peritoneal space (PS) to replace bowel loops (BL) via the dose constraint method to spare the small bowel during intensity-modulated radiotherapy (IMRT) for rectal cancer. Methods: A total of 24 patients with rectal cancer who underwent adjuvant or neoadjuvant radiotherapy were selected. Weekly repeat CT scans from pre-treatment to the fourth week of treatment were acquired and defined as Plan, 1W, 2W, 3W, and 4W. The 4 weekly CT scans were co-registered to the Plan CT, BL and PS contours were delineated in all of the scans, an IMRT plan was designed on Plan CT using PS constraint method, and then copied to the 4 weekly CT scans. The dose-volume, normal tissue complication probability (NTCP) of the small bowel and their variations during treatment were evaluated. Results: Overall, 109 sets of CT scans from 24 patients were acquired, and 109 plans were designed and copied. The BL and PS volumes were 250.3 cc and 1339.3 cc. The V15 of BL and PS based plan of pre-treatment were 182.6 cc and 919.0 cc, the shift% of them were 28.9% and 11.3% during treatment (p=0.000), which was less in the prone position than in the supine position (25.2% vs 32.1%, p =0.000; 9.9% vs 14.9%, p=0.000). The NTCPC and NTCPA based plan of pre-treatment were 2.0% and 59.2%, the shift% during treatment were 46.1% and 14.0% respectively. Majority of BL’s Dmax and V15 were meet the safety standard during treatment using PS dose limit method except 3 times (3/109) of V15 and 5 times of Dmax (5/109).Conclusions: This study indicated that small bowel motion may lead to uncertainties in its dose volume and NTCP evaluation during IMRT for rectal cancer. The BL movements were significantly greater than PS, and the prone position was significantly less than the supine position. It is feasibility of using PS to replace BL to spare the small bowel, V15<830 cc is the dose constraint standard.

Evaluation of Small Bowel Motion and Feasibility of using the Peritoneal Space to Replace Bowel Loops for Dose Constraints during Intensity-Modulated Radiotherapy for Rectal Cancer

Background The goal of this study was to assess small bowel motion and explore the feasibility of using peritoneal space (PS) to replace bowel loops (BL) via the dose constraint method to spare the small bowel during intensity-modulated radiotherapy (IMRT) for rectal cancer. Methods A total of 24 patients with rectal cancer who underwent adjuvant radiotherapy were selected. Weekly repeat CT scans from pre-treatment to the fourth week of treatment were acquired and defined as Plan, 1W, 2W, 3W, and 4W. BL and PS contours were delineated in all of the scans. Two IMRT plans called PPS and PBL were designed on Plan CT using two dose PS and BL constraint methods, respectively, and then copied to CT 1 ~ 4W. The shift%, dose volume, and NTCP of the small bowel in PPS and PBL during treatment were evaluated. Results Overall, 109 sets of CT scans from 24 patients were acquired, and 218 plans were designed and copied. The PS and BL volumes were 1339.28 cc and 250.27 cc. The BL and PS shift% V15 was 28.48% and 11.79% (p = 0.000), which was less in the prone position than in the supine position (25.24% vs 32.10%, p = 0.000; 9.9% vs 14.85%, p = 0.000). On all of the CT scans, most PPS small bowel dose volumes were less than from PBL. V15 was 170.07 cc vs 178.58 cc (p = 0.000), and they had a significant correlation. The NTCP of chronic and acute side effects from PPS was significantly less than PBL (2.80% vs 3.00%, p = 0.018; 57.32% vs 58.64%, p = 0.000). Conclusions This study indicated that small bowel motion may lead to uncertainties in its dose volume and NTCP evaluation during IMRT for rectal cancer. The BL movements were significantly greater than PS, and the prone position was significantly less than the supine position. Using PS instead of BL can spare the small bowel. V15 < 830 cc is the dose constraint standard.