[Gastrointestinal stromal tumors: potential of minimally invasive surgical interventions]

OBJECTIVE

To analyze the issue of gastrointestinal stromal tumors (GISTs) and potential of minimally invasive surgical interventions.

MATERIAL AND METHODS

We analyzed postoperative outcomes in 97 patients with gastric and intestinal GISTs who underwent surgical treatment at the National Medical Research Centre for Oncology between 2015 and 2020.

RESULTS

Twenty (24.7) patients with gastric GISTs underwent laparoscopic partial and distal gastric resections. Five (35.7%) patients with GISTs of the small intestine underwent minimally invasive segmental bowel resections. Only minimally invasive interventions were performed in patients with rectal GISTs. Analysis of laparoscopic and open surgeries for GISTs found no significant differences. Analysis of laparoscopic and open surgeries for gastric and small bowel GISTs revealed the obvious advantages of minimally invasive access regarding postoperative outcomes. Indeed, we found no need for nasogastric drainage in 50% of patients (p<0.001), earlier recovery of intestinal motility and oral feeding (p<0.001), lower postoperative morbidity (p=0.036), fast recovery of motor activity (p<0.001) and shorter postoperative hospital-stay (p<0.001).

CONCLUSION

Despite small incidence, GISTs are a complex problem in modern oncology. Diagnosis and treatment require a multidisciplinary medical team (morphologists, geneticists, radiologists, surgeons, chemotherapists, gastroenterologists and other specialists) that is possible in a reference center. Minimally invasive interventions for GISTs of the stomach, small intestine and rectum improve postoperative course.

Liver metastasis or a pseudocyst? A rare presentation of leiomyosarcoma's metastasis in the liver

Gastrointestinal neoplasms most commonly metastasize to the liver, where they are typically found as solid and hypervascular lesions. Here, we describe a case of a 44-year-old man with a leiomyosarcoma of the rectum, who at the time of diagnosis presented with a small (5 mm in diameter) cyst-like lesion in the liver. Positron emission tomography demonstrated no increased metabolism in the area of the cyst, suggesting a benign character of the lesion. However, after 3 years, CT scans revealed enlargement of the cyst, and local surgical excision was performed. The results of histopathological examination of the resected material were consistent with metastatic leiomyosarcoma. Subsequently, the patient developed lung metastases and died within 2 years. Our case describes a very rare presentation of leiomyosarcoma's metastasis that led to an ill-fated misdiagnosis and dismal disease outcome.

Risk factors and treatment of rectal stenosis after transanal endoscopic microsurgery

AIM

Rectal stenosis is a relatively rare complication after transanal endoscopic microsurgery (TEM). This study aims to identify the predictive parameters for stenosis and the application of TEM in the treatment.

METHOD

The clinical data of patients who underwent TEM for rectal adenoma and early cancer from 2008 to 2019 were retrospectively reviewed. We compared the clinicopathological characteristics of patients with stenosis and those without stenosis and analysed the risk factors for stenosis. Treatment outcomes of stenosis with TEM were evaluated.

RESULTS

A total of 230 patients were enrolled in this study. Overall, the postoperative complication rate was 11.7% (27/230), including eight (3.5%) patients with stenosis. Patients with stenosis exhibited a higher rate of tumour showing a laterally spreading morphology (P = 0.048), a wider circumferential extent of mucosal defect (P < 0.001), a shorter distance of the tumour from the anal verge (P = 0.001) and a wider longitudinal extent of mucosal defect (P = 0.027). A circumferential extent of mucosal defect >3/4 (OR 94.945, 95% CI 3.611-2496.41, P = 0.006) was identified as the only independent risk factor for stenosis. The four patients with both stenosis and clinical symptoms were treated by incising the stenosis ring using the TEM platform; the stenosis was cured, and symptoms disappeared after one to four courses of treatment.

CONCLUSIONS

Circumferential extent of mucosal defect ≥3/4 was an independent risk factor for stenosis in treating rectal adenoma and early cancer with TEM. Incision of the stenosis ring using the TEM platform is an effective strategy for treating stenosis.

Pediatric Colorectal Carcinoma: A Series of Seven Cases

Introduction

Colorectal carcinoma (CRC) accounts for <1% of all the neoplasms of children. Unfavorable histology and delayed diagnosis often result in poor outcome. This study aimed to investigate the clinical characteristic and prognosis of pediatric patients with CRC.

Materials and Methods

A retrospective review of medical records of all patients diagnosed of CRC between 2015 and 2020 was performed. Data regarding gender, age, location, and histopathology were collected.

Results

Seven children (5 males and 2 females) were included in the study. Age ranged between 8.6 and 11.8 years. Abdominal pain was the most common symptom. The duration between onset of symptoms to the diagnosis ranged from 5 days to 8 months. Right-sided tumors were more common than the left side. Histopathological examination showed mucinous adenocarcinoma in four/seven patients and signet cell variant was seen in 2/7. Immunohistochemistry was positive for cytokeratin and beta-catenin, however, all microsatellite instability markers were found negative. Despite surgical treatment and chemotherapy, four of our cases faced mortality and one patient was lost to follow-up.

Conclusion

CRC can present in first decade of life and often misdiagnosed. Pediatric CRC has distinct tumor biology and shares a poor prognosis. Paucity of literature from the Indian subcontinent should urge further clinicopathological trials for establishing etiology and for refining treatment recommendations in these children.

Diagnostic performance of MRI and endoscopy for assessing complete response in rectal cancer after neoadjuvant chemoradiotherapy: a systematic review of the literature

BACKGROUND

The diagnostic performance of magnetic resonance imaging (MRI) modalities and/or endoscopy for assessing complete response in rectal cancer after neoadjuvant chemoradiotherapy (nCRT) is unclear.

PURPOSE

To summarize existing evidence on the diagnostic performance of diffusion-weighted MRI, perfusion-weighted MRI, T2-weighted MR tumor regression grade, and/or endoscopy for assessing complete tumor response after nCRT.

MATERIAL AND METHODS

MEDLINE and Embase databases were searched. The PRISMA guidelines were followed. Sensitivity, specificity, negative predictive, and positive predictive values were retrieved from included studies.

RESULTS

In total, 81 studies were eligible for inclusion. Evidence suggests that combined use of MRI and endoscopy tends to improve the diagnostic performance compared to single imaging modality. The positive predictive value of a complete response varies substantially between studies. There is considerable heterogeneity between studies.

CONCLUSION

Combined re-staging tends to improve diagnostic performance compared to single imaging modality, but the vast majority of studies fail to offer true clinical value due to the study heterogeneity.

Radiology reporting in rectal cancer using MRI: adherence to national template for structured reporting

BACKGROUND

In 2014, a national workshop program was initiated and a reporting template and manual for rectal cancer primary staging using magnetic resonance imaging (MRI) was introduced and made available by the national Swedish Colorectal Cancer Registry.

PURPOSE

To evaluate the effect of the national template program by identify if there was a gap between the content in Swedish MRI reports from 2016 and the national reporting template from 2014. The aim was to explore and compare differences in content in reporting practice in different hospitals in relation to the national reporting template, with focus on: (i) identifying any implementational differences in reporting styles; and (ii) evaluating if reporting completeness vary based on such implementational differences.

MATERIAL AND METHODS

A total of 250 MRI reports from 10 hospitals in four healthcare regions in Sweden were collected. Reports were analyzed using qualitative content analysis with a deductive thematic coding scheme based on the national reporting template.

RESULTS

Three different implemented reporting styles were identified with variations of content coverage in relation to the template: (i) standardized and structured protocol (reporting style A); (ii) standardized semi-structured free-text (reporting style B); and (iii) regular free-text (reporting style C). The relative completeness of reporting practice of rectal cancer staging in relation to the national reporting template were 92.9% for reporting style A, 77.5% for reporting style B, and 63.9% for reporting style C.

CONCLUSION

The implementation of template-based reporting according to reporting style A is a key factor to conform to evidence-based practice for rectal cancer reporting using MRI.

Linitis plastica of the rectum secondary to metastatic prostate cancer: A case report of a rare presentation and literature review

Linitis plastica is a rare tumor with poor prognosis. It is a circumferentially infiltrating intramural tumor which can result in rigid, nondistensible thickening of the affected organ. It most commonly affects the stomach, followed by the rectum, and can be due to primary or secondary cancer. Secondary rectal linitis plastica (RLP) caused by metastatic cancers has been reported from the stomach, breast, gallbladder, urinary bladder, and very rarely, the prostate, with only <5 reported cases in the literature. We report the case of a 66-year-old man who presented with altered bowel habit and loss of weight, with elevated prostate-specific antigen of 180.6 ng/mL. Sigmoidoscopy showed thickened rectal mucosa, and biopsy was negative for malignancy. Magnetic resonance imaging showed circumferential wall thickening, "target sign" appearance suggestive of RLP, PIRADS 5 lesion with extraprostatic extension, infiltrating bilateral seminal vesicles, and right neurovascular bundle. Repeat colonoscopy was performed under anesthesia, and deeper biopsy revealed poorly differentiated metastatic prostate adenocarcinoma. This case report highlights the atypical presentation of metastatic prostate cancer secondary to RLP, the rarity of this condition, and emphasizes the importance of deeper biopsy in RLP due to disease involvement predominantly in the submucosa and muscularis propria layers.

Isolated Rectal Tuberculosis in Immunocompetent Host

Abdominal tuberculosis (TB) is the sixth most common site for extrapulmonary TB. Ileocecal region is the most common site for it, and its incidence reduces as we move proximally and distally from it. Isolated rectal TB in an immunocompetent person is very rare, and it usually mimics as rectal carcinoma. The yield of endoscopic biopsies for granuloma is low due to submucosal location of these lesions, and mostly, they are diagnosed after surgical intervention. We report a case of isolated rectal TB in a middle-aged female who present with chronic diarrhea and was diagnosed by the presence of epithelioid cells forming granulomas and acid-fast bacilli in rectal biopsy.

Colorectal Cancer in Uganda: A 10-Year, Facility-Based, Retrospective Study

Introduction

Colorectal cancer (CRC) is the most common type of gastrointestinal malignancies and the third leading cause of cancer-related deaths for both sexes worldwide. Although the burden of CRC is highest in developed countries, reports are indicating a rise in the incidence of early-onset CRC in developing countries. In this study, we aimed to determine the prevalence of CRC among patients hospitalized with lower gastrointestinal complaints at a tertiary health facility in Uganda.

Methods

We conducted a 10-year retrospective chart review of patients admitted to Mulago National Referral Hospital in Kampala, Uganda, between 1st January 2010 and 31st December 2020. We reviewed all charts of patients admitted to the lower gastrointestinal tract (GIT) ward. Charts with grossly missing data, pediatric patients, and those from other non-lower GIT specialties were excluded.

Results

Data of 1476 unique eligible patients were analyzed. Of these,138 had a diagnosis of CRC (prevalence: 9.3%, 95% confidence interval (95% CI): 6.5-11.7%). Among patients with CRC, the female:male ratio was 1:1. The most common site for CRC was the rectum (59.8%, n= 79). For the 138 participants with CRC, 44 had staging data with 72.8% (n=32) having advanced disease, that is, stage 3 or 4. Factors independently associated with CRC were age ≥50 years (adjusted odds ratio (aOR): 4.3, 95% CI: 2.6-7.1, p < 0.001), female sex (aOR: 1.8, 95% CI: 1.2 -2.8, p = 0.005), being widowed (aOR: 2.5, 95% CI: 1.3-5.0, p = 0.006), and presence of any risk factor for CRC (aOR: 5.3, 95% CI: 2.9-9.9, p < 0.001).

Conclusion

CRC is relatively common among patients hospitalized with lower GIT complaints, particularly among women and those with known risk factors for CRC. Awareness creation and screening programs should be instituted to allow early diagnosis of CRC in our setting.

Extranodal Follicular dendritic cell sarcoma presenting as a rectal polyp: An entity overlooked by its differentials

Extranodal follicular dendritic cell sarcoma (ENFDCS) is a rare hematolymphoid tumor, masquerading as soft tissue sarcoma on initial histological examination. So, for its confirmation, the application of immunohistochemistry (IHC) is of paramount importance. Over the years there has been a major shift in the demography of follicular dendritic cell sarcoma (FDCS), with a rise in the number of extranodal cases. Herein we report a case of ENFDCS presenting as a rectal polyp, who had a history of intermittent bleeding per rectum and passage of fleshy mass while defecation. As these tumors share an overlapping morphology with other spindle cell tumors and can occur at unpredictable locations, they pose a diagnostic challenge, especially for young pathologists.

Rectal mixed adenoneuroendocrine carcinoma: Case report

RATIONALE

Colorectal mixed neuroendocrine-nonneuroendocrine neoplasms constitute a rare group of gastrointestinal tumors composed by both neuroendocrine and nonneuroendocrine components. Nondiagnostic macroscopic features, specific histological features, and poor awareness of the disease are responsible for the underestimated incidence and conflicting data available. Due to lack of randomized clinical trials and validated clinical guidelines, diagnostic and therapeutic approach are based on the standard of care for pure colorectal neuroendocrine carcinomas or adenocarcinomas.

PATIENT CONCERNS

A 76-year-old caucasian male, without relevant medical or familial history, presented a positive faecal occult blood test during colorectal cancer screening.

DIAGNOSIS

Total colonoscopy identified a rectal lesion with biopsy showing a moderate rectal adenocarcinoma staged as cT2N0M0.

INTERVENTIONS

Anterior resection of the rectum with right ileostomy followed by local radiotherapy with radio-sensitising chemotherapy and adjuvant chemotherapy with capecitabine 1000 mg bid plus oxaliplatin 130 mg/m2. Due to chronic nodular pulmonary aspergillosis and chemotherapy induced immunosuppression patient was on 400 mg/daily of oral voriconazole.

OUTCOMES

Overall survival of 15 months after progression under first line treatment and under palliative chemotherapy with platinum plus etoposide regimen.

LESSONS

The reported case illustrates the challenge associated to the management of mixed neuroendocrine-nonneuroendocrine carcinomas due to lack of validated guidelines and scientific evidence. From diagnosis and staging to treatment, all steps must be tailored to individual clinical and histological features.

Reducing systematic errors due to deformation of organs at risk in radiotherapy

PURPOSE

In radiotherapy (RT), the planning CT (pCT) is commonly used to plan the full RT-course. Due to organ deformation and motion, the organ shapes seen at the pCT will not be identical to their shapes during RT. Any difference between the pCT organ shape and the organ's mean shape during RT will cause systematic errors. We propose to use statistical shrinkage estimation to reduce this error using only the pCT and the population mean shape computed from training data.

METHODS

The method was evaluated for the rectum in a cohort of 37 prostate cancer patients that had a pCT and 7-10 treatment CTs with rectum delineations. Deformable registration was performed both within-patient and between patients, resulting in point-to-point correspondence between all rectum shapes, which enabled us to compute a population mean rectum. Shrinkage estimates were found by combining the pCTs linearly with the population mean. The method was trained and evaluated using leave-one-out cross validation. The shrinkage estimates and the patient mean shapes were compared geometrically using the Dice similarity index (DSI), Hausdorff distance (HD), and bidirectional local distance. Clinical dose/volume histograms, equivalent uniform dose (EUD) and minimum dose to the hottest 5% volume (D5%) were compared for the shrinkage estimate and the pCT.

RESULTS

The method resulted in moderate but statistically significant increase in similarity to the patient mean shape over the pCT. On average, the HD was reduced from 15.6 to 13.4 mm, while the DSI was increased from 0.74 to 0.78. Significant reduction in the bias of volume estimates was found in the DVH-range of 52.5-65 Gy, where the bias was reduced from -1.3 to -0.2 percentage points, but no significant improvement was found in EUD or D5%, CONCLUSIONS: The results suggest that shrinkage estimation can reduce systematic errors due to organ deformations in RT. The method has potential to increase the accuracy in RT of deformable organs and can improve motion modeling.

Fascial Organisation and Lymphatic Systems Around the Pelvic Floor: A Literature Review

This review summarises the anatomy and lymphatic systems around the pelvic floor. We investigated the lymphovascular network in the anorectal region, focusing on the hiatal ligament, which comprises smooth muscle fibres derived from the longitudinal muscle and connecting the anal canal and coccyx, and the endopelvic fascia, which seems to comprise collagen and elastic fibres. During rectal surgery, endopelvic fascia is recognized as a sheet of fascia covering the levator ani muscle. Endopelvic fascia is extensively attached to the smooth muscle fibres diverging from the longitudinal muscle of the rectum. Analysis of the lymphovascular network using submucosal India ink injection and indocyanine green fluorescence imaging suggests a functional lymphatic flow between rectal muscle fibres and hiatal ligament and endopelvic fascia. Precise analysis of the lymphatic systems of fascial organization around the pelvic floor may be useful in formulating therapeutic strategies for low rectal cancer.

Endoscopic ultrasound-guided drainage of intra-abdominal diverticular abscess. A case series

AIM

Diverticular disease is widespread worldwide. Mainstay approach is non-operative treatment with bowel rest and broad-spectrum intravenous antibiotics. However, extra-colic abscess larger than 4 cm may require percutaneous trans-abdominal drainage. We report a single centre case series of patients underwent to trans-luminal endoscopic ultrasound (EUS)-guided drainage of pelvic abscess in diverticular disease with temporary placement of lumen apposing metal stent (LAMS).

METHODS

All patients referred to our tertiary centre from January 2019 to July 2020 were enrolled in a prospective data base that was retrospectively analysed. Procedural steps were as follows: pre-operative computed tomography scan, broad-spectrum antibiotic therapy, EUS-guided deployment of LAMS for 15 days, LAMS removal and deployment of pigtail stent in case of pseudo-cavity persistence.

RESULTS

Ten patients (6F) with an average of 59.6 years were enrolled with deployment of 10 LAMS. One patient was excluded after EUS evaluation and 1 patient had 2 LAMS for 2 separate abscesses. Technical and clinical success was achieved in 88.8% (8/9).

CONCLUSIONS

Management of diverticulitis has shifted from primary surgical intervention towards a non-operative approach of bowel rest and broad-spectrum intravenous antibiotics in conjunction with interventional procedures to drain abscesses whenever necessary. EUS-guided drainage with LAMS for the management of diverticular abscesses seems an efficient treatment modality for encapsulated abscesses more than 4 cm in size and close to colonic wall. In expert centres, it may avoid radiologic intervention and/or surgery in a relevant percentage of cases.

Successful Endoscopic Resection of Primary Rectal Mucosa-Associated Lymphoid Tissue Lymphoma by Endoscopic Submucosal Dissection: A Case Report

Mucosa-associated lymphoid tissue (MALT) lymphoma arises in extra-nodal sites from the malignant transformation of B lymphocytes that are mainly triggered by infection or autoimmune process. MALT lymphoma is frequently detected in the gastrointestinal tract. As the causal relationship between Helicobacter pylori (H. pylori) infection and gastric MALT lymphoma, it was well-established that early-stage gastric MALT lymphoma could be cured by H. pylori eradication, and about 50–95% of cases achieved complete response with anti-H. pylori treatment. Compared to the stomach which is the most involved site due to the high prevalence of H. pylori infection, the colorectum is rarely affected. Primary rectal MALT lymphoma is a rare malignancy, and there are no specific therapeutic strategies so far. Here we report a case of rectal MALT lymphoma successfully resected by endoscopic submucosal dissection (ESD). ESD serves as a novel strategy to cure small localized rectal MALT lymphomas to avoid unnecessary surgery or chemo-radiotherapy.

Trends in the Incidence and Survival Rates of Colorectal Signet-Ring Cell Carcinoma in the South Korean Population: Analysis of the Korea Central Cancer Registry Database

Objective: Signet-ring cell carcinoma (SRCC) is a rare histopathological subtype of colorectal cancer (CRC) constituting approximately 1% of CRC cases. This study analyzed the incidence and survival rates of colorectal SRCC. Methods: We analyzed the incidence and survival rates of colorectal SRCCs based on patients’ data of the Korea Central Cancer Registry. Results: The age-standardized incidence rates of colon and rectum SRCC in 2017 were 0.17 and 0.07 individuals per 100,000, respectively. Between 1993 and 2017, the 1-, 2-, 3-, 4-, and 5-year relative survival rates of patients with colon SRCC were 65.6%, 49.0%, 38.9%, 34.9%, and 33.0%, respectively, while those of patients with rectum SRCC were 69.6%, 47.8%, 38.5%, 32.8%, and 29.4%, respectively. According to the Surveillance, Epidemiology, and End Results summary stages, the 5-year relative survival rates of colon SRCC between 1993 and 2017 were 70.4% for the localized stage, 41.0% for the regional stage, and 7.0% for the distant stage, while those for rectum SRCC were 60.7%, 34.4, and 3.3%, respectively. Conclusions: Although the incidence of colorectal SRCC is extremely low in South Korea, it has been increasing in recent decades. As the prognosis of colorectal SRCC is extremely poor; clinicians should be aware of the differential diagnosis of SRCC in colorectal cancer cases.

Rectal inflammatory myofibroblastic tumor: Case report and literature review

RATIONALE

Rectal inflammatory myofibroblastic tumor (IMT) is an extremely rare mesenchymal tumor characterized by a mixture of spindle-shaped myofibroblasts or fibroblasts and inflammatory infiltration of lymphocytes and plasma cells. To date, only 8 cases of rectal IMT have been reported. Herein, we report an additional case of rectal IMT in a 28-year-old woman.

PATIENT CONCERNS

A 28-year-old woman presented with abdominal pain and hematochezia.

DIAGNOSES

Colonoscopy showed a 3.0-cm subepithelial tumor with central ulceration, covered by white exudate in the rectum. Rectal magnetic resonance imaging revealed a 4.0 × 3.0-cm-sized well-defined subepithelial tumor in the right wall of the rectum, with suspicious right perirectal fat infiltration.

INTERVENTIONS

Laparoscopic anterior resection was performed. Microscopic examination of the surgical specimen revealed bland-looking spindle cells intermingled with lymphoplasma cells. Immunohistochemistry and fluorescence in situ hybridization showed anaplastic lymphoma kinase positivity and anaplastic lymphoma kinase positivity rearrangement. Rectal IMT was confirmed based on histological, immunohistochemical, and fluorescence in situ hybridization findings. The patient was doing well without evidence of tumor recurrence 1 year after the surgery.

LESSONS

Rectal IMT, despite its rarity, should be considered in the differential diagnosis of rectal cancer. Second, an accurate histopathologic diagnosis and complete surgical resection can be the most important approaches to offer a chance for the cure of rectal IMT.

Rectum sizes: Assessment by ultrasonography in children with functional constipation

AIM

This study aimed to compare the transverse diameter and thickness of the anterior wall of the rectum in children with normal bowel movement and children with functional constipation in different age groups. Another objective was to find correlations of rectum sizes with faecal incontinence and constipation duration.

METHODS

In the study, we included children with normal bowel movement and functional constipation diagnosed based on the Rome III and Rome IV criteria. We collected clinical data from the parents. We measured the rectum transverse diameter and the thickness of the anterior wall by abdominal ultrasound.

RESULTS

The study included 65 children, 31 with normal bowel movement and 34 with functional constipation. The rectum transverse diameter and the thickness of the anterior wall had statistically significant higher values in patients with constipation (P < 0.05). There was a moderate and significant correlation between the duration of the disease (mean ± standard deviation = 31.7 ± 33.1 months) and rectum transverse diameter (r = 0.54; P = 0.0009). The rectum transverse diameter correlated moderately with the presence of faecal incontinence (r = 0.62; P = 0.003), but the thickness of the anterior wall did not correlate with this symptom (r = 0.02; P = 0.39).

CONCLUSIONS

We found statistically significant differences between the transverse rectal diameter and thickness of the rectum anterior wall, measured by abdominal ultrasound, in children with functional constipation compared with normal defaecation patterns. Faecal incontinence and long-term constipation were correlated with the increased rectum diameter.

The effect of neoadjuvant imatinib therapy on outcome and survival in rectal gastrointestinal stromal tumors: A multiinstitutional study

BACKGROUND AND OBJECTIVES

This study aimed to characterize the efficacy of neoadjuvant imatinib in rectal gastrointestinal stromal tumors (GISTs) and the prognostic characteristics of patients after surgery.

METHODS

Patients with rectal GISTs who received neoadjuvant imatinib between 2000 and 2019 were selected from 11 large-scale tertiary hospitals in China. The best response to neoadjuvant imatinib was assessed. Propensity score matching (PSM) was conducted to reduce confounders. Recurrence free survival (RFS) and overall survival (OS) were estimated using Kaplan-Meier method.

RESULTS

Of the 100 patients, 75, 18, and 7 had a partial response (PR), stable disease (SD), and progressive disease (PD), respectively. The median tumor size decreased from 5 cm before treatment to 4 cm after treatment (p < 0.001). A total of 31 patients underwent genetic testing after surgery; 23 of patients with exon 11 mutation had PR and 2 had SD. One of the patients with exon 9 mutation had PR, 2 had SD, and 1 had PD. Two patients with the wild type GIST had PD. A total of 86 patients underwent surgery of which 85 underwent complete resection; 72 underwent anal preservation and 40 underwent local excision (LE). After PSM, patients who received neoadjuvant therapy had higher rates of LE (p = 0.001) and anal preservation (p = 0.033) than those of patients without neoadjuvant therapy. The median follow-up time was 37 months. Nine patients experienced recurrence and one patient died. The 3-year RFS and OS rates were 95.0% and 100%, respectively. After PSM, we found that there was no significant difference in RFS between patients who received or did not receive neoadjuvant therapy (p = 0.623). Univariate analysis showed postneoadjuvant tumor size (p = 0.469) and mitotic count (p = 0.294) were not associated with the RFS in patients who received neoadjuvant imatinib.

CONCLUSIONS

Neoadjuvant imatinib can shrink rectal GIST size, increasing the possibility of complete resection and anal preservation. Further studies are warranted to understand the long-term outcomes of rectal GISTs in patients receiving neoadjuvant imatinib.

Case series of retained rectal foreign body. A Malaysian experience

Retained rectal foreign body, with its associated social stigma, is a medical condition that is infrequently reported in Malaysia. We report the surgical management of five cases of retained foreign objects in the rectum seen over a one-year period. There were three young and two elderly male patients. One of the elderly patients presented with altered bowel habits and an abdominal mass that mimicked a symptomatic colonic tumor. All patients had an abdominal radiograph which clinched the diagnosis of a retained foreign rectal body. Successfully retrieved objects included two bottles, one bidet device, and two sex toys. Open surgery for retrieval of the impacted rectal foreign body was required in one patient. All underwent successful retrievals without any adverse postoperative complications. In our case series, retained rectal foreign bodies were observed only in the male gender. The age presentation was bimodal, with age groups in the twenties and sixties. The treatment options used for the retrieval of these impacted foreign bodies included transanal extraction or explorative laparotomy. Proximal migration and delayed presentation are possible indications for the latter approach.

Laparoscopic intraarterial catheterization with selective ICG fluorescence imaging in colorectal surgery

The quality of mesorectal resection is crucial for resection in rectal cancer, which should be performed by laparoscopy for better outcome. The use of indocyanine green (ICG) fluorescence is now routinely used in some centers to evaluate bowel perfusion. Previous studies have demonstrated in animal models that selective intra-arterial ICG staining can be used to define and visualize resection margins in rectal cancer. In this animal study, we investigate if laparoscopic intra-arterial catheterization is feasible and the staining of resection margins when performing total mesorectal excision with a laparoscopic medial to lateral approach is possible. In 4 pigs, laparoscopic catheterization of the inferior mesenteric artery (IMA) is performed using a seldinger technique. After a bolus injection of 10 ml ICG with a concentration of 0.25 mg/ml, a continuous intra-arterial perfusion was established at a rate of 2 ml/min. The quality of the staining was evaluated qualitatively. Laparoscopic catheterization was possible in all cases, and the average time for this was 30.25 ± 3.54 min. We observed a significant fluorescent signal in all areas of the IMA supplied, but not in other parts of the abdominal cavity or organs. In addition, the mesorectum showed a sharp border between stained and unstained tissue. Intraoperative isolated fluorescence augmentation of the rectum, including the mesorectum by laparoscopic catheterization, is feasible. Inferior mesenteric artery catheterization and ICG perfusion can provide a fluorescence-guided roadmap to identify the correct plane in total mesorectal excision, which should be investigated in further studies.

Short- and Long-Term Outcomes of Robotic Surgery for Rectal Neuroendocrine Tumor

Background. The optimal radical surgical approach for rectal neuroendocrine tumor (NET) is unknown. Methods. This study evaluated the short- and long-term outcomes of 27 patients who underwent robotic radical surgery for rectal NET between 2011 and 2019. Results. The median distance from the lower border of the tumor to the anal verge was 5.0 cm. The median tumor size was 9.5 mm. Six patients (22%) had lymph node metastasis. The incidences of postoperative complications of grade II and grade III or more according to the Clavien-Dindo classification were 11% and 0%, respectively. All patients underwent sphincter-preserving surgery, and no patients required conversion to open surgery. The median follow-up time was 48.9 months, and both the 3-year overall survival and relapse-free survival rates were 100%. Conclusions. Short- and long-term outcomes of robotic surgery for rectal NET tumor were favorable. Robotic surgery may be a useful surgical approach for rectal NET.

Unusual intra-rectal "laterally spreading tumour" in immunosuppressed patient with ulcerative colitis

Condyloma acuminatum (CA) is a manifestation of Human Papillomavirus (HPV) infection which usually occurs in genital and perianal regions. We report a 46-year-old man with an ulcerative proctitis diagnosed four years earlier, asymptomatic for a long time under azathioprine but without any follow-up for three years. A colonoscopy was performed prior to potential immunosuppressive treatment discontinuation and showed a circumferential "laterally spreading tumour" in the rectum. Surprisingly biopsies revealed a CA with a very focally high-grade intra-epithelial lesion. Azathioprine was stopped and a transanal surgical resection was performed. At guided anamnesis, patient confirmed to be a former active "men who have sex with men". No recurrence of proctitis occurred despite azathioprine discontinuation. A retrospective review of the histological sections suggests that it was, in fact, an intestinal spirochetosis misdiagnosed as inflammatory bowel disease. Involvement of the rectal mucosa by HPV is a rare condition and this may have been promoted by inappropriate immunosuppressive treatment.

Late Gastrointestinal Tolerance After Prostate Radiotherapy: Is the Anal Canal the Culprit? A Narrative Critical Review

Introduction

Late gastro-intestinal toxicities (LGIT) secondary to pelvic radiotherapy (RT) are well described in the literature. LGIT are mainly related to rectal or ano-rectal irradiation; however, involvement of the anal canal (AC) in the occurrence of LGIT remains poorly described and understood.

Materials and Methods

The aim of this work was to explore the potential role of the AC in the development of LGIT after prostate irradiation and identify predictive factors that could be optimized in order to limit these toxicities. This narrative literature review was realized using the Pubmed database. We identified original articles published between June 1997 and July 2019, relating to LGIT after RT for localized prostate cancer and for which AC was identified independently. Articles defining the AC as part of an anorectal or rectal volume only were excluded.

Results

A history of abdominal surgery or cardio-vascular risk, anticoagulant or tobacco use, and the occurrence of acute GIT during RT increases the risk of LGIT. A dose-effect relationship was identified between dose to the AC and development of LGIT. Identification and contouring of the AC and adjacent anatomical structures (muscles or nerves) are justified to apply specific dose constraints. As a limitation, our review mainly considered on 3DCRT which is no longer the standard of care nowadays; we did not identify any reports in the literature using moderately hypofractionated RT for the prostate and AC specific dosimetry.

Conclusion

These results suggest that the AC may have an important role in the development of LGIT after pelvic RT for prostate cancer. The individualization of the AC during planning should be recommended in prospective studies.