Radical resection versus local excision for low rectal gastrointestinal stromal tumor: A multicenter propensity score-matched analysis

BACKGROUND

The surgical approaches and resection extent for rectal gastrointestinal stromal tumors (GISTs) are controversial due to the low incidence of this disease. A multicenter retrospective cohort study was conducted to compare the postoperative and oncologic outcomes of local excision (LE) and radical resection (RR) in patients with low rectal GIST.

PATIENTS AND METHODS

The medical records of rectal GIST patients from 11 large-scale medical centers in China (January 2000-December 2019) were reviewed. All patients were divided into either the LE group or the RR group. Propensity score matching (PSM) was conducted to reduce confounders.

RESULTS

A total of 280 patients with low rectal GIST were enrolled. After PSM, 144 patients were included (72 in each group). The LE group showed a higher anal preservation rate (100.0% vs. 76.4%, P < 0.001), shorter operation time (77.1 ± 68.4 min vs. 159.1 ± 83.6 min, P < 0.001), fewer complications (8.3% vs. 22.2%, P = 0.021) and shorter postoperative hospital stay (4.9 ± 4.1 d vs. 10.7 ± 8.1 d, P < 0.001) than the RR group. There was no significant difference in recurrence-free survival (RFS) between the RR and LE groups among patients with tumors ≤2 cm (P = 0.220), and the RR group had a superior RFS than the LE group in patients with tumors >2 cm (P = 0.046).

CONCLUSIONS

LE resulted in improved postoperative outcomes and comparable oncological safety with a low rectal GIST of ≤2 cm. However, for patients with a low rectal GIST of >2 cm, RR might be a more appropriate option with better RFS.

Re-exploring the pelvic neuroanatomy from a new perspective and a potential guidance for TaTME: a "bottom-up" approach

Neuro-anatomy of the perineum has gained renewed attention due to its significance in the transanal procedures for rectal cancer (eg TaTME). Surgeons embarking on this technique must have sophisticated knowledge and a precise anatomical understanding of the perineum before proceeding with this reversed rectal approach. We report anatomical observations deriving from a relevant experience in the colorectal surgery field. The collective multicenter experience of the present study is clinically relevant and based on the rectal and transanal resections performed in colorectal centers of excellence from Greece, UK, and Italy over the last 10 years (2011-2020). From the original anatomical and intraoperative observations derived from collective cases operated by this multicenter group of colorectal surgical centers in three European countries, data were retrieved and analyzed in collaboration with specialist researchers of human anatomy and interpreted for their clinical significance and potential use for preoperative planning and intraoperative guidance during TaTME. This descriptive article demonstrates in detail the neurogenic pathways encountered in the perineum and pelvic cavity during transanal procedures. Specific anatomical and topographic implications are also included serving as a guide for colorectal surgeons to perform a nerve-sparing procedure. transanal approach for rectal excision offers new insights into the complex pelvic and perineal neuroanatomy while the procedure itself remains a challenge for surgeons. Preoperative anatomical planning and 3D reconstruction may help in anticipating technical difficulties, resulting in more precise surgical dissections and decreased postoperative complications.

Rectal Metastases of Breast Carcinoma: A Case Report

The scarcely reported hematogenous rectal metastases from breast cancer are rare and the diagnosis is challenging. They may be recognized before, concomitantly with, or after the diagnosis of the primary site of breast cancer. Invasive lobular cancer is the histological type more frequently described, and most of the affected patients have a late diagnosis. Tardive recognition is associated with poor outcomes, despite the management options. Endoscopic and imaging evaluations, mainly magnetic resonance studies, are useful, but the anatomopathological findings are mandatory to confirm the diagnostic hypothesis. We describe a middle-aged woman with advanced rectal metastases of unsuspected breast cancer found during the evaluation of manifestations due to intestinal implants. One must highlight long-term follow-up of breast cancers even if seeming in remission. The aim of this report is to enhance the suspicion index of primary health care workers.

Hybrid imaging of the abdomen and pelvis

Accurate imaging is crucial for lesion detection in abdominal organs, for the noninvasive characterization of focal and diffuse abnormalities, and for surgical planning. To accomplish these tasks, several imaging modalities such as multidetector computer tomography (MDCT), magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) are used for abdominal imaging, providing important morphological, functional or metabolic information. More recently, PET/MRI has been gaining attention due to the possibility of combining high-resolution imaging with metabolic imaging. PET/MRI is a novel hybrid imaging technology that in the near future might play a pivotal role in the clinical management of oncologic and inflammatory abdominopelvic diseases. Despite the still limited number of published clinical studies, PET/MRI has been proven to be at least equivalent to PET/CT and to standalone MRI in a variety of oncologic disease. Moreover, in selected and focused clinical studies, it has been proven to outperform current standard of care imaging, for example, in evaluating cholangiocarcinomas, liver metastases, untreated and treated rectal cancer. This has also had an impact on therapeuticmanagement in some studies. Therefore in some institutions, including those of the authors, PET/MRI is becoming the new standard imaging modality in staging treatment-naïve intrahepatic massforming cholangiocarcinomas and prior to complicated hepatic surgery.

Long-term Prognosis of Localized Lymphoid Hyperplasia of the Rectum

Background/Aims

Although localized lymphoid hyperplasia (LLH) of the rectum is occasionally observed, its clinical implications are unclear. This study aimed to investigate the clinical course and significance of LLH of the rectum.

Methods

We identified 65 patients diagnosed with LLH of the rectum using a histopathologic examination and who received follow-up endoscopies between January 2009 and June 2015. Patients with a history of inflammatory bowel disease, lymphoma, familial adenomatous polyposis, or uncontrolled malignancy and patients who underwent scar biopsy after endoscopic resection or surgery were excluded. Endoscopic findings and clinical courses were analyzed.

Results

During the median follow-up of 31 months (interquartile range, 19 to 40 months), 81.5% (53/65) of LLHs of the rectum were resolved. Clinically significant diseases, including ulcerative colitis (UC, n=5) and mucosa-associated lymphoid tissue (MALT) lymphoma (n=1), were diagnosed in 9.2% of patients (6/65). The other six patients showed no significant changes in the lesion (n=3) or a waxing and waning appearance (n=3). According to endoscopic findings, all of the 47 polypoid types showed resolution or waxing and waning patterns. Five of the 11 nodular types (45.5%) developed into UC. One of the seven submucosal tumor (SMT)-like types (14.3%) developed into MALT lymphoma.

Conclusions

LLH of the rectum with persistent symptoms or the endoscopic appearance of the nodular or SMT-like type may lead to clinically significant disease. Risk stratification according to endoscopic findings and careful surveillance are required for these lesions.

Evaluation of margins in pelvic lymph nodes and prostate radiotherapy and the impact of bladder and rectum on prostate position

PURPOSE

The aims of this study were: determination of the CTV to PTV margins for prostate and pelvic lymph nodes. Investigation of the impact of registration modality (pelvic bones or prostate) on the CTV to PTV margins of pelvic lymph nodes. Investigation of the variations of bladder and rectum over the treatment course. Investigation of the impact of bladder and rectum variations on prostate position.

PATIENTS AND METHODS

This study included 15 patients treated for prostate adenocarcinoma. Daily kilo voltage images and weekly CBCT scans were performed to assess prostate displacements and common and external iliac vessels motion. These data was used to calculate the CTV to PTV margins using Van Herk equation in the setting of a daily bone registration. We also compared the CTV to PTV margins of pelvic lymph nodes according to registration method; based on pelvic bone or prostate. We delineated bladder and rectum on all CBCT scans to assess their variations over treatment course at 4 anatomic levels [1.5cm above pubic bone (PB), superior edge, mid- and inferior edge of PB].

RESULTS

Using Van Herk equation, the prostate CTV to PTV margins (bone registration) were 8.03mm, 5.42mm and 8.73mm in AP, ML and SI direction with more than 97% of prostate displacements were less than 5mm. The CTV to PTV margins ranged from 3.12mm to 3.25mm for external iliac vessels and from 3.12mm to 4.18mm for common iliac vessels. Compared to registration based on prostate alignment, bone registration resulted in an important reduction of the CTV to PTV margins up to 54.3% for external iliac vessels and up to 39.6% for common iliac vessels. There was no significant variation of the mean bladder volume over the treatment course. There was a significant variation of the mean rectal volume before and after the third week of treatment. After the third week, the mean rectal volume seemed to be stable. The uni- and multivariate analysis identified the anterior wall of rectum as independent factor acting on prostate motion in AP direction at 2 levels (superior edge of, mid PB). The right rectal wall influenced the prostate motion in ML direction at inferior edge of PB. The bladder volume tends toward significance as factor acting on prostate motion in AP direction.

CONCLUSIONS

We recommend CTV to PTV margins of 8mm, 6mm and 9mm in AP, ML and SI directions for prostate. And, we suggest 4mm and 5mm for external and common iliac vessels respectively. We also prefer registration based on bony landmarks to minimize bowel irradiation. More CBCT scans should be performed during the first 3weeks and especially the first week to check rectum volume.

Early postoperative pain as a marker of anastomotic leakage in colorectal cancer surgery

PURPOSE

Even though anastomotic leakage after colorectal surgery is a major clinical problem in need of a timely diagnosis, early indicators of leakage have been insufficiently studied. We therefore conducted a population-based observational study to determine whether the patient's early postoperative pain is an independent marker of anastomotic leakage.

METHODS

By combining the Swedish Colorectal Cancer Registry and the Swedish Perioperative Registry, we retrieved prospectively collected data on 3084 patients who underwent anastomotic colorectal surgery for cancer in 2014-2017. Postoperative pain, measured with the numerical rating scale (NRS), was considered exposure, while anastomotic leakage and reoperation due to leakage were outcomes. We performed logistic regression to evaluate associations, estimating odds ratios (ORs) and 95% confidence intervals (CIs), while multiple imputation was used to handle missing data.

RESULTS

In total, 189 patients suffered from anastomotic leakage, of whom 121 patients also needed a reoperation due to leakage. Moderate or severe postoperative pain (NRS 4-10) was associated with an increased risk of anastomotic leakage (OR 1.69, 95% CI 1.21-2.38), as well as reoperation (OR 2.17, 95% CI 1.41-3.32). Severe pain (NRS 8-10) was more strongly related to leakage (OR 2.38, 95% CI 1.44-3.93). These associations were confirmed in multivariable analyses and when reoperation due to leakage was used as an outcome.

CONCLUSION

In this population-based retrospective study on prospectively collected data, increased pain in the post-anaesthesia care unit is an independent marker of anastomotic leakage, possibly indicating a need for further diagnostic measures.

Endoscopic full thickness resection vs. transanal endoscopic microsurgery for local treatment of rectal neuroendocrine tumors - a retrospective analysis

PURPOSE

Local treatment of small well-differentiated rectal neuroendocrine tumors (NETs) is recommended by current guidelines. However, although several endoscopic methods have been established, the highest R0 rate is achieved by transanal endoscopic microsurgery (TEM). Since a recently published study about endoscopic full thickness resection (eFTR) showed a R0 resection rate of 100%, the aim of this study was to evaluate both methods (eFTR vs. TEM).

METHODS

We retrospectively analyzed all patients with rectal NET treated either by TEM (1999-2018) or eFTR (2016-2019) in two tertiary centers (University Hospital Wuerzburg and Ulm). We analyzed clinical, procedural, and histopathological outcomes in both groups.

RESULTS

Twenty-eight patients with rectal NET received local treatment (TEM: 13; eFTR: 15). Most tumors were at stage T1a and grade G1 or G2 (in the TEM group two G3 NETs were staged T2 after neoadjuvant chemotherapy). In both groups, similar outcomes for en bloc resection rate, R0 resection rate, tumor size, or specimen size were found. No procedural adverse events were noted. Mean procedure time in the TEM group was 48.9 min and 19.2 min in the eFTR group.

CONCLUSION

eFTR is a convincing method for local treatment of small rectal NETs combining high safety and efficacy with short interventional time.

Three distinct outcomes in patients with colorectal adenocarcinoma and lymphovascular invasion: the good, the bad, and the ugly

PURPOSE

In colorectal cancer (CRC), lymphovascular invasion (LVI) is a predictor of poor outcome and its analysis is nowadays recommended. Literature is still extremely heterogeneous, and we hypothesize that, within such a group of patients, there are any further predictors of survival.

METHODS

A total of 2652 patients with I-III-stage CRC undergoing resection between 2002 and 2018 were included in a retrospective analysis of demographic, clinical, and histology with the aim of defining the impact of LVI on overall survival (OS) and its relationship with other prognostic factors.

RESULTS

Overall, 5-year-OS was 62.6% (77-month-median survival). LVI was found in 558 (21%) specimens and resulted associated with 44.9%-5-year-OS (44 months) vs. 64.1% (104 months) of LVI cases. At multivariate analysis, LVI (p = 0.009), T3-4 (p < 0.001), and N ≠ 0 (p < 0.001) resulted independent predictors of outcome. LVI resulted as being associated with older age (p < 0.013), T3-4 (p < 0.001), lower grading (p < 0.001), N ≠ 0 (p < 0.001), mucinous histology (p < 0.001), budding (p < 0.001), and PNI (p < 0.001). Within the LVI + patients, T3-4 (p = 0.009) and N ≠ 0 (p < 0.001) resulted as independent predictors of shortened OS. In particular, N-status impacted the prognosis of patients with T3-4 tumors (p = 0.020), whereas it did not impact the prognosis of patients with T1-2 tumors (p = 0.393). Three groups (T1-2anyN, T3-4N0, T3-4 N ≠ 0), with distinct outcome (approximately 70%-, 52%-, and 35%-5-year-OS, respectively), were identified.

CONCLUSIONS

LVI is associated with more aggressive/more advanced CRC and is confirmed as predictor of poor outcome. By using T- and N-stage, a simple algorithm may easily allow re-assessing the expected survival of patients with LVI + tumors.

Small-cell neuroendocrine carcinoma of the rectum - a rare tumor type with poor prognosis: A case report and review of literature

BACKGROUND

Small-cell neuroendocrine carcinoma (SNEC) of the rectum is a rare tumor associated with poor prognosis.

CASE SUMMARY

We report a case of a 77-year-old male who came into our hospital because of blood with his stool. An endoscopy revealed a cauliflower-like neoplasm in his rectum. Imaging examination showed that the lesion in the upper rectum was likely rectal cancer, and there was no evidence of metastasis. The patient was treated with surgery. Pathological examination confirmed SNEC of the rectum and an R0 resection was achieved. However, 1 mo after the operation, the patient developed intestinal and ureteral obstructions due to peritoneal metastases. Finally, the patient died from renal failure.

CONCLUSION

SNEC of the rectum is a high-grade carcinoma with an aggressive phenotype, and surgery should be cautiously considered.

Low-grade Rectal Neuroendocrine Tumor Recurring as Multiple Hepatic Metastasis after Complete Endoscopic Removal: A Case Report

The World Health Organization classified rectal neuroendocrine tumors (NETs) as malignant in 2010 owing to their distant metastasis potential. On the other hand, in cases of small rectal NETs (<10 mm), which have a low risk of metastasis, endoscopic removal is the first-line therapeutic option, and regular surveillance is not recommended. The authors report a case of a small, well-differentiated rectal NET, which recurred as multiple hepatic metastases 5 years after apparent complete removal using endoscopic methods.

Emergency laparoscopic resection of the anterior rectum due to rectal trauma secondary to compressed air, case report

In the XIX century, the surgeon faces surgical challenges due to the creation of new technologies. Accidental or compressed air-induced injury to the colon and rectum is rare. We present the case of a 45-year-old patient who consults the emergency department, then a high-pressure rectal pneumatic trauma, with clinical findings of peritonism, managed with a Hartmann-type colostomy. and anterior resection of the rectum using laparoscopy, with findings of rectosigmoid perforation. With this, it can be demonstrated that minimally invasive surgery is a feasible approach in hemodynamically unstable patients without contraindication for pneumoperitoneum.

Simultaneous triple cancer of the esophagus, pancreas and rectum treated with multimodal strategies: a case report

BACKGROUND

Due to the development of diagnostic imaging technology, we have increased chance of detecting multiple primary cancers. However, simultaneous triple cancer is still a very rare finding whose frequency is not yet known. Treatment of simultaneous triple cancer is a clinical challenge because it requires multimodal strategies including surgery, chemotherapy and radiotherapy.

CASE PRESENTATION

Here, we present the case of a 74-year-old male with triple cancer involving esophageal and pancreatic cancer, and rectal carcinoma. Each cancer was surgically resectable, but simultaneous resection of all cancers seemed to cause too much surgical stress for the patient. First, we performed a laparoscopic Hartmann's operation for rectal cancer to minimize the risk of postoperative complications. Then treatment for pancreatic cancer was initiated by administering neoadjuvant chemotherapy with gemcitabine plus nab-paclitaxel. The pancreatic tumor shrank in size, so pancreatoduodenectomy was performed. We chose S-1 as adjuvant chemotherapy. The esophageal cancer showed regression during the treatment of the other two cancers, likely because the chemotherapeutic agents administered for pancreatic cancer had some effect on the esophageal cancer. Definitive chemoradiotherapy was selected instead of esophagectomy because the patient had already undergone two major surgeries. The patient is still alive nine months after the whole course of treatment with no sign of recurrence.

CONCLUSIONS

The treatment of triple cancer requires an elaborate strategy to determine which cancer has to be dealt with first and which can be treated later. An aggressive multimodal treatment strategy may be an important option for a patient with triple cancer.

Current Surgical Strategies for the Treatment of Rectal Adenocarcinoma and the Risk of Local Recurrence

BACKGROUND

Despite new medical and surgical strategies, 5-year local recurrence of rectal adenocarcinoma was reported in up to 25% of cases. Therefore, we aimed to review surgical strategies for the prevention of local recurrences in rectal cancer.

SUMMARY

After implementation of the total mesorectal excision (TME), surgical resection of rectal adenocarcinoma with anterior resection or abdominoperineal excision (APE) allowed decrease in local recurrence (3% at 5 years). More recently, extralevator APE was described as an alternative to APE, decreasing specimen perforation and recurrence rate. Moreover, technique modifications were developed to optimize rectal resection, such as the laparoscopic or robotic approach, and transanal TME. However, the technical advantages conferred by these techniques did not translate into a decreased recurrence rate. Lateral lymph node dissection is another technique, which aimed at improving the long-term outcomes; nevertheless, there is currently no evidence to recommend its routine use. Strategies to preserve the rectum are also emerging, such as local excision, and may be beneficial for subgroups of patients. Key Messages: Rectal cancer management requires a multidisciplinary approach, and surgical strategy should be tailored to patient factors: general health, previous perineal intervention, anatomy, preference, and tumor characteristics such as stage and localization.

Polypoid Endometriosis of the Rectum and Vagina in an Adolescent

BACKGROUND

Polypoid endometriosis (PEM) is a rare type of endometriosis, frequently mimicking a malignant tumor. We report on a patient with PEM over a 10-year span who had symptoms at age 16.

CASE

A 20-year-old woman presented with massive vaginal hemorrhage and spontaneous abortion, having symptoms of dysmenorrhea, anal distending pain, and vaginal bleeding since adolescence. Imaging showed multiple polypoid neoplasms of the rectum and vagina connecting to the huge mass in a cul de sac. After exploration and excision, the pathology revealed PEM.

Management of colon and rectal cancers during COVID-19 pandemic: A clinical guideline (TUMS-CRC-CoV19 Guideline)

Background: In a resource-demanding COVID-19 pandemic, guidelines can free up health care resources needed for providing better care to those with COVID-19 and other patients. This study was performed to design a guideline to manage patients with colorectal cancers during the COVID-19pandemic.

Methods: To design this guideline, major topics and headings of colon and rectal cancers (CRC) were selected and included. Based on the extent of COVID-19 infection in the community and availability of hospital resources, the guideline has been designed for 2 major COVID-19 phases. Several multidisciplinary discussion sessions were held to review the comments of experts, finalize the data, and write the guideline.

Results: This guideline has been prepared in 2 main COVID-19 phases of the community/hospital. Phase A refers to the condition where a large number of COVID-19 patients are admitted to the hospital, but limited surgical ICU beds and facilities are still accessible. In phase B, many people are affected by COVID-19, and all hospital resources are allocated for COVID 19 patients. In phase A, 4 major groups are discussed, including malignant and suspicious colorectal polyps, colon cancers, rectal cancers, and recurrent cancers. The approach to emergent cases, including obstruction, bleeding, and perforation, will be presented in phase B.

Conclusion: This guideline is a comprehensive instruction on the approach to colorectal cancers during the COVID-19 pandemic that covers the major topics of colon and rectal cancers in detail.

Efficacy and safety of endoscopic submucosal tunnel dissection for rectal laterally spreading tumors

BACKGROUND

Evidence that comprehensively compares the efficacy and safety of endoscopic submucosal tunnel dissection (ESTD) with endoscopic submucosal dissection (ESD) for rectal laterally spreading tumors (LSTs) is limited.

METHODS

Between January 2009 and June 2018, 143 rectal LSTs in 143 patients who had undergone either ESD (n = 84) or ESTD (n = 59) were included in the study. One-to-one propensity score matching (PSM) was performed, and 50 pairs were selected. The data on patient demographics, treatment information, pathology reports, adverse events and follow-up were collected.

RESULTS

Before PSM, the median specimen area was significantly larger in the ESTD group than in the ESD group (12.56 cm² vs. 6.32 cm², respectively; p < 0.001). The median dissection speed was significantly higher in the ESTD group than in the ESD group (24.53 mm²/min vs. 15.16 mm²/min, respectively; p < 0.001). After PSM, the median dissection speed was significantly higher in the ESTD group than in the ESD group (23.80 mm²/min vs. 17.12 mm²/min, respectively; p < 0.001). In multiple linear regression analysis, significant factors related to a higher dissection speed were the treatment method of ESTD (p < 0.001) and larger specimen area (p < 0.001).

CONCLUSIONS

ESTD appears to be a safe and effective method to treat rectal LSTs. Compared with ESD, ESTD appears to achieve a higher dissection speed for rectal LSTs.

Primary Rectal Non-Hodgkin's Lymphoma Treated with Urgent Radiotherapy and Chemotherapy: A Case Report and Literature Review

Rectal malignancy is usually symptomatic due to its location, and most of the time presents with pain and bleeding due to its growth and ulceration. It is difficult to identify the primary as carcinoma or lymphoma based on symptoms only, as both have a similar presentation. As it presents the rarest form of histology, non-Hodgkin's lymphoma in the rectum is still difficult to diagnose initially, and its treatment is debatable. We describe the case of a 49-year-old male from Bangladesh with the same presentation. His treatment was delayed for more than a month as immunohistochemistry and staging delayed the final diagnosis. The disease was diagnosed as stage IE with the help of a positron emission tomography (PET)-CT scan, and due to the local progression the patient had a massive rectal bleeding that needed an urgent intervention. Radiotherapy was applied to stop the bleeding. Hypofraction followed by a conventional fraction of external beam radiotherapy (EBRT) with a total of 40 Gy was applied. Post-EBRT digital rectal examination showed no residual except scaring, and a PET scan was also negative for residual disease. Due to uncertainties and lack of any precious guideline, 6 cycles of adjuvant chemotherapy with the R-CHOP schedule were also completed. Without surgery, the combination of EBRT and chemotherapy helped to preserve the organ, and the patient has been disease free for more than 2.5 years since his treatment.

MRI of rectal cancer-relevant anatomy and staging key points

Rectal cancer has the eighth highest cancer incidence worldwide, and it is increasing in young individuals. However, in countries with a high human development index, mortality is decreasing, which may reflect better patient management, imaging being key. We rely on imaging to establish the great majority of clinical tumour features for therapeutic decision-making, namely tumour location, depth of invasion, lymph node involvement, circumferential resection margin status and extramural venous invasion. Despite major improvements in technique resulting in better image quality, and notwithstanding the dissemination of guidelines and examples of standardised reports, rectal cancer staging is still challenging on the day-to-day practice, and we believe there are three reasons. First, the normal posterior pelvic compartment anatomy and variants are not common knowledge to radiologists; second, not all rectal cancers fit in review paper models, namely the very early, the very low and the mucinous; and third, the key clinical tumour features may be tricky to analyse. In this review, we discuss the normal anatomy of the rectum and posterior compartment of the pelvis, systematise all rectal cancer staging key points and elaborate on the particularities of early, low and mucinous tumours. We also include our suggested reporting templates and a discussion of its comparison to the reporting templates provided by ESGAR and SAR.

Feasibility of Simultaneous Multislice Acceleration Technique in Diffusion-Weighted Magnetic Resonance Imaging of the Rectum

Objective

To assess the feasibility of simultaneous multislice-accelerated diffusion-weighted imaging (SMS-DWI) of the rectum in comparison with conventional DWI (C-DWI) in rectal cancer patients.

Materials and Methods

This study included 65 patients with initially-diagnosed rectal cancer. All patients underwent C-DWI and SMS-DWI with acceleration factors of 2 and 3 (SMS2-DWI and SMS3-DWI, respectively) using a 3T scanner. Acquisition times of the three DWI sequences were measured. Image quality in the three DWI sequences was reviewed by two independent radiologists using a 4-point Likert scale and subsequently compared using the Friedman test. Apparent diffusion coefficient (ADC) values for rectal cancer and the normal rectal wall were compared among the three sequences using repeated measures analysis of variance.

Results

Acquisition times using C-DWI, SMS2-DWI, and SMS3-DWI were 173 seconds, 107 seconds, (38.2% shorter than C-DWI), and 77 seconds (55.5% shorter than C-DWI), respectively. For all image quality parameters other than distortion (margin sharpness, artifact, lesion conspicuity, and overall image quality), C-DWI and SMS2-DWI yielded better results than did SMS3-DWI (Ps < 0.001), with no significant differences observed between C-DWI and SMS2-DWI (Ps ≥ 0.054). ADC values of rectal cancer (p = 0.943) and normal rectal wall (p = 0.360) were not significantly different among C-DWI, SMS2-DWI, and SMS3-DWI.

Conclusion

SMS-DWI using an acceleration factor of 2 is feasible for rectal MRI resulting in substantial reductions in acquisition time while maintaining diagnostic image quality and similar ADC values to those of C-DWI.

Case Report: Management of rectal squamous cell carcinoma - a treatment dilemma

Primary rectal squamous cell carcinoma is rare compared to adenocarcinoma, which is the predominant histologic type most commonly discovered at the time of colorectal carcinoma diagnosis. Due to the infrequent nature of this malignancy, data on tumor pathogenesis and risk factors remains sparse. Moreover, no standardized therapeutic regimen exists. This report describes a case of advanced rectal squamous cell carcinoma diagnosed in a 46-year-old female who initially presented with abdominal pain. Her clinical course was uncomplicated and she responded well to the selected therapy. Much work remains to be accomplished for patients with rectal squamous cell carcinoma.

Rectal endometriosis: predictive MRI signs for segmental bowel resection

OBJECTIVE

To retrospectively determine the accuracy of MRI rectal and pararectal signs in predicting the necessity for segmental resection in the case of lesions located in the rectum.

METHODS

MR images of consecutive patients treated for rectal endometriosis over a 5-year period were reviewed in consensus by two blinded readers. A systematic analysis of 7 rectal (lesion length, transverse axis, thickness and circumference, and presence of a convex base, submucosal oedema and hyperintense cystic areas) and 4 pararectal (posterior vaginal fornix, parametrial, ureteral and sacro-recto-genital septum involvements) signs was performed for each lesion. MRI results were compared to the surgical procedure performed (shaving versus segmental resection).

RESULTS

Among 61 patients studied, 32 received a segmental resection and 29, a shaving. Receiver operating characteristic curve analysis allowed determining cut-off values for length (≥ 32 mm), transverse axis (≥ 22 mm), thickness (≥ 14 mm) and circumference (≥ 3/8 radii). The 7 rectal signs, and only the sacro-recto-genital septum pararectal sign, were significantly associated with segmental resection in univariate analysis, nodular thickness ≥ 14 mm and circumference ≥ 3/8 radii being the most predictive signs (odds ratio 94.5 and 60.4, respectively). These 2 signs remained positively associated with segmental resection in multivariate analysis and, when combined, were predictive of segmental resection with an accuracy of 90.2%.

CONCLUSION

Assessing MRI rectal and pararectal signs may accurately predict the need for segmental resection versus a more conservative approach such as shaving for rectal lesion management.

KEY POINTS

• MRI analysis of rectal endometriosis, taking into account rectal and pararectal signs, may assist surgeons in the decision-making process, in counselling patients regarding the surgical procedure and in adequately allocating resources. • Among rectal signs, nodular thickness ≥ 14 mm and a circumference ≥ 38% were the most predictive signs of segmental resection. • Among pararectal signs, only the sacro-recto-genital septum involvement was significantly associated with segmental resection.

Primary Localized Amyloidosis of the Intestine: A Pathologist Viewpoint

Background

Localized amyloidosis of the intestine is a rare entity, which can clinically masquerade several conditions such as colitis, polyps, and malignant tumors. This study aims to evaluate the clinicopathological features of this entity.

Methods

To evaluate the clinicopathological features of this entity, a comprehensive search of the literature (1960 to 2019) was done using the following keywords: "amyloidosis" and "small intestine" or "duodenum" or "ileum" or "jejunum" or "colon". We identified 756 studies about gastrointestinal amyloidosis. Data were examined for 27 studies about localized intestinal amyloidosis. The clinicopathological features were described.

Results

The age at presentation ranged from 29 to 88 years. The male to female ratio was 3:1. The jejunum and sigmoid colon were the most commonly involved sites. Abdominal pain and intestinal obstruction (small intestine), or rectal bleeding (sigmoid region) were the most common clinical presentations. Colonoscopic findings included wall thickening, mucosal ulcerations (small intestine), and tumor-like masses (colon).

Conclusions

The clinical presentations of localized intestinal amyloidosis depend on the site of the deposition of the amyloid. In most cases, amyloid deposits consisted of light chain protein.

Diffusion tensor imaging of rectal carcinoma: Clinical evaluation and its correlation with histopathological findings

OBJECTIVE

This study sought to assess the feasibility of diffusion tensor imaging (DTI) to noninvasively evaluate histological grade and lymph node metastasis in patients with rectal carcinoma (RC).

METHODS

Thirty-seven consecutive patients with histologically confirmed RC were examined by 1.5-T MRI. DTI was performed using a single-shot echo-planar imaging sequence with b values of 0 and 1000 s/mm² and motion-probing gradients in nine noncollinear directions. Fractional anisotropy (FA), axial diffusivity (AD), mean diffusivity (MD), and radial diffusivity (RD) maps were compared with histopathological findings.

RESULTS

The FA values (0.357 ± 0.047) of the RCs were significantly lower than those of the normal rectal wall, muscle, prostate, and uterus (P < 0.001 for all), while the AD, MD, and RD values (1.221 ± 0.131, 0.804 ± 0.075, and 0.667 ± 0.057 × 10^-3 mm²/s, respectively) were also significantly lower than their respective normal values (P < 0.001 for all). The FA, AD, MD, and RD values for RC additionally showed significant inverse correlations with histological grades (r = -0.781, r = -0.750, r = -0.718, and r = -0.682, respectively; P < 0.001 for all). Further, the FA (0.430 vs. 0.611), AD (1.246 vs. 1.608 × 10^-3 mm²/s), MD (0.776 vs. 1.036 × 10^-3 mm²/s), and RD (0.651 vs. 0.824 × 10^-3 mm²/s) (P < 0.001 for all) of the metastatic and nonmetastatic lymph nodes were significantly different.

CONCLUSIONS

DTI may be clinically useful for the noninvasive evaluation of histological grade and lymph node metastasis in patients with RC.