Small Cell Carcinoma of the Rectum-An Unexpected Diagnosis: Current Treatment Options for a Rare and Aggressive Entity.

Rectal small cell carcinoma is a rare and aggressive cancer subtype for which a consensus of optimal treatment has not yet been reached. This cancer presents a difficult surgical problem, and thus, the mainstay of treatment tends to mirror that of small cell carcinoma of the lung (chemotherapy, radiation therapy, and immune modulators). This brief report highlights current treatment options available for this rare and difficult entity. There is a significant need for large-center clinical trials and prospective studies to help determine the best treatment regimen to effectively care for patients with small cell carcinoma of the rectum.

Diagnostic accuracy of endoscopy in determining rectal tumor proximity to the peritoneal reflection.

PURPOSE: Treatment of invasive rectal adenocarcinoma is stratified into upfront surgery versus neoadjuvant chemoradiotherapy, in part, based on tumor distance from the anal verge (AV). This study examines the correlation between tumor distance measurements (endoscopic and MRI) and relationship to the anterior peritoneal reflection (aPR) on MRI. METHODS: A single-center retrospective study was performed at a tertiary center accredited by the National Accreditation Program for Rectal Cancer (NAPRC). 162 patients with invasive rectal cancer were seen between October of 2018 and April of 2022. Sensitivity and specificity were determined for MRI and endoscopic measurements in their ability to predict tumor location relative to the aPR. RESULTS: One hundred nineteen patients had tumors endoscopically and radiographically measured from the AV. Pelvic MRI characterized tumors as above (intraperitoneal) or at/straddles/below the aPR (extraperitoneal). True positives were defined as extraperitoneal tumors [Formula: see text] 10 cm. True negatives were defined as intraperitoneal tumors > 10 cm. Endoscopy was 81.9% sensitive and 64.3% specific in predicting tumor location with respect to the aPR. MRI was 86.7% sensitive and 92.9% specific. Utilizing a 12 cm cutoff, sensitivity of both modalities increased (94.3%, 91.4%) but specificity decreased (50%, 64.3%). CONCLUSION: For locally invasive rectal cancers, tumor position relative to the aPR is an important factor in determining the role of neoadjuvant therapy. These results suggest endoscopic tumor measurements do not accurately predict tumor location relative to the aPR, and may lead to incorrect treatment stratification recommendation. When the aPR is not identified, MRI-reported tumor distance may be a better predictor of this relationship.

Locally Transplanted Adipose Stem Cells Reduce Anastomotic Leaks in Ischemic Colorectal Anastomoses: A Rat Model.

BACKGROUND: Anastomotic leakage remains a dreaded complication after colorectal surgery. Stem-cell-based therapies have been shown to increase angiogenesis and cell proliferation. OBJECTIVE: The purpose of this research was to investigate the use of adipose-derived stem cells on the healing of ischemic colonic anastomoses in a rat model. DESIGN: This is an animal research study using xenotransplantation. SETTINGS: Male Wistar rats (300-400 g, n = 48) were purchased from a licensed breeder. PATIENTS: Adipose stem cells were isolated from the subcutaneous fat of healthy human donors. INTERVENTIONS: The rats underwent laparotomy with creation of an ischemic colorectal anastomosis created by ligation of mesenteric vessels. The animals were divided into 3 groups: control group with an ischemic anastomosis, vehicle-only group in which the ischemic anastomosis was treated with an absorbable gelatin sponge, and a treatment group in which the ischemic anastomosis was treated with an absorbable gelatin sponge plus adipose stem cells. Animals were killed at postoperative days 3 and 7. MAIN OUTCOME MEASURES: Anastomotic leakage was defined as the finding of feculent peritonitis or perianastomotic abscess on necropsy. Rat mRNA expression was measured using real-time polymerase chain reaction. RESULTS: Adipose-derived stem cells significantly decreased anastomotic leakage when compared with control at both postoperative days 3 (25.0% vs 87.5%; p = 0.02) and 7 (25.0% vs 87.5%; p = 0.02). The use of an absorbable gelatin sponge alone had no effect on anastomotic leakage when compared with control and postoperative days 3 or 7. We found that stem cell-treated animals had a 5.9-fold and 7.4-fold increase in the expression of vascular endothelial growth factor when compared with control at 3 and 7 days; however, this difference was not statistically significant when compared with the absorbable gelatin sponge group. LIMITATIONS: This is a preclinical animal research study using xenotransplantation of cultured stem cells. CONCLUSIONS: Locally transplanted adipose stem cells enhance the healing of ischemic colorectal anastomoses and may be a novel strategy for reducing the risk of anastomotic leakage in colorectal surgery. See Video Abstract at http://links.lww.com/DCR/B203. EL TRANSPLANTE LOCAL DE CÉLULAS MADRE ADIPOSAS REDUCE LA FUGA ANASTOMÓTICA EN LAS SUTURAS COLORRECTALES ISQUÉMICAS: MODELO EN RATAS: Las fugas anastomóticas son una complicación pusilánime después de toda cirugía colorrectal. Se ha demostrado que el tratamiento con células madre aumenta la angiogénesis y la proliferación celular.Investigar el uso de células madre derivadas de tejido adiposo en la cicatrización de una anastomosis colónica isquémica basada en ratas como modelo.Estudio de investigación en animales utilizando xenotrasplantes.Adquisición de típicas ratas de laboratorio raza Wistar, todas machos (300-400 g, n = 48) de un criadero autorizado.Aislamiento de células madre de tipo adiposo del tejido celular subcutáneo en donantes humanos sanos.Las ratas se sometieron a laparotomía con la creación de una anastomosis colorrectal isquémica obtenida mediante ligadura controlada de los vasos mesentéricos correspondientes. Los animales se dividieron en tres grupos: grupo de control con anastomosis isquémica, grupo de vehículo único en el que la anastomosis isquémica se trató con una esponja de gelatina absorbible, y un grupo de tratamiento en el que la anastomosis isquémica se trató con una esponja de gelatina absorbible asociada a un vástago adiposo de células madre. Los animales fueron sacrificados el POD3 y el POD7.La fuga anastomótica fué definida como el hallazgo de peritonitis fecaloidea o absceso perianastomótico a la necropsia. La expresión de RNAm de las ratas se midió usando PCR en tiempo real.Las células madre derivadas de tejido adiposo disminuyeron significativamente la fuga anastomótica en comparación con el grupo control tanto en el POD3 (25% frente a 87.5%, p = 0.02) como en el POD7 (25% frente a 87.5%, p = 0.02). El uso de una esponja de gelatina absorbible sola, no tuvo efecto sobre la fuga anastomótica en comparación con los controles el POD3 o el POD7. Descubrimos que los animales tratados con células madre adiposas tenían un aumento de 5,9 y 7,4 veces en la expresión de VEGF en comparación con el control a los 3 y 7 días, respectivamente; sin embargo, esta diferencia no fue estadísticamente significativa en comparación con el grupo de esponja de gelatina absorbible.Este es un estudio preclínico de investigación en animales que utiliza xenotrasplantes de células madre adiposas cultivadas.Las células madre de tipo adiposo trasplantadas localmente mejoran la cicatrisación en casos de anastomosis colorrectales isquémicas, y podrían convertirse en una nueva estrategia para reducir el riesgo de fugas anastomóticas en casos de cirugía colorrectal. Consulte Video Resumen en http://links.lww.com/DCR/B203. (Traducción-Dr Xavier Delgadillo).

Oral Versus Intravenous Acetaminophen within an Enhanced Recovery after Surgery Protocol in Colorectal Surgery.

BACKGROUND: Multimodal pain management within enhanced recovery after surgery (ERAS) protocols is designed to decrease opioid use, promote mobilization, and decrease postoperative complications. OBJECTIVES: To evaluate the role of intravenous (IV) versus oral (PO) acetaminophen within an established ERAS protocol in colorectal surgery. STUDY DESIGN: This was a retrospective observational study. SETTING: This research took place within an established perioperative colorectal surgery protocol. METHODS: A total of 91 consecutive elective colorectal resections performed according to an ERAS protocol using only IV acetaminophen (IV group) were compared with 84 consecutive resections performed using one dose of IV acetaminophen followed by subsequent administration of oral acetaminophen (PO group). Our multimodal pain management strategy also included transverse abdominis plane blocks, celecoxib, and ketorolac medications for both groups. Opioid requirements, maximum and average daily pain scores by the Visual Analog Scale, and postoperative outcomes were compared between groups. RESULTS: There were no differences in maximum or average pain scores on postoperative days 0-3 or at time of discharge between IV and PO groups. Compared with the IV acetaminophen only group, the PO group received significantly more perioperative opioids through 72 hours postoperatively (68.8 oral morphine equivalents [OME] IV group vs. 93.7 OME PO group; P < 0.0001), were more likely to require opioid patient-controlled analgesia (8.9% IV group vs. 46.4% PO group; P < 0.0001), and were more likely to experience postoperative nausea and vomiting (33.0% IV group vs. 48.8% PO group; P = 0.0449). LIMITATIONS: Significant limitations include the studies' retrospective nature and that it was performed at a single institution. CONCLUSIONS: Restriction of IV acetaminophen within an ERAS protocol in colorectal surgery was associated with increased opioid use, greater need for opioid patient-controlled analgesia, and increased incidence of postoperative nausea and vomiting. IV acetaminophen may be superior to oral acetaminophen in the early postoperative setting. KEY WORDS: Perioperative pain management, enhanced recovery after surgery, acetaminophen, multimodal pain control, nonopioid.

Success of referral to genetic counseling after positive lynch syndrome screening test.

PURPOSE: Lynch syndrome (LS) is a hereditary condition that increases one's risk of developing colorectal, endometrial, and other extracolonic cancers. MD Anderson Cancer Center at Cooper implemented a reflex screening protocol for DNA mismatch repair (dMMR) deficiency. Those with findings suspicious for LS were referred for genetic counseling (GC). Our goal was to assess compliance with GC and factors associated with successful follow-up. METHODS: Immunohistochemistry (IHC) for the MMR proteins MSH2, MLH1, MSH6, and PMS2 was performed on all colorectal tumor resections from patients ≤70 years old and all stage II cancers. Tumors with loss of MLH1/PMS2 were subsequently tested for BRAF mutation or MLH1 promoter methylation to identify tumors with likely epigenetic inactivation of MLH1. Patients with loss of MLH1/PMS2 without BRAF mutations or with absence of MLH1 promoter methylation and those with loss of MSH2/MSH6 were referred to GC. Compliance with GC was assessed. RESULTS: Between March 2014 and August 2016, 203 tumors were tested by IHC. Fifteen (7.4%) patients had abnormal MMR protein expression patterns in the absence of BRAF mutation or MLH1 promoter methylation suggestive of possible LS. GC compliance was 35.7% overall and 85.7% in those with family history of LS-associated cancers. CONCLUSIONS: Overall, GC compliance was relatively low in our study. Interestingly, patients with a strong family history of LS-associated neoplasms were more likely to pursue GC. In the future, assessing and addressing barriers to seeking GC will provide opportunities to improve patient care through increased identification of patients with cancer predisposition syndromes.

Is low-molecular-weight heparin safe for venous thromboembolism prophylaxis in patients with traumatic brain injury? A Western Trauma Association multicenter study.

BACKGROUND: Venous thromboembolism (VTE) is a significant risk in trauma patients. Although low-molecular weight heparin (LMWH) is effective in VTE prophylaxis, its use for patients with traumatic intracranial hemorrhage remains controversial. The purpose of this study was to evaluate the safety of LMWH for VTE prophylaxis in blunt intracranial injury. METHODS: We conducted a retrospective multicenter study of LMWH chemoprophylaxis on patients with intracranial hemorrhage caused by blunt trauma. Patients with brain Abbreviated Injury Scale score of 3 or higher, age 18 years or older, and at least one repeated head computed tomographic scan were included. Patients with previous VTE; on preinjury anticoagulation; hospitalized for less than 48 hours; on heparin for VTE prophylaxis; or required emergent thoracic, abdominal, or vascular surgery at admission were excluded. Patients were divided into two groups: those who received LMWH and those who did not. The primary outcome was progression of intracranial hemorrhage on repeated head computed tomographic scan. RESULTS: The study included 1,215 patients, of which 220 patients (18.1%) received LMWH and 995 (81.9%) did not. Hemorrhage progression occurred in 239 of 995 control subjects and 93 of 220 LMWH patients (24% vs. 42%, p < 0.001). Hemorrhage progression occurred in 32 patients after initiating LMWH (14.5%). Nine of these patients (4.1%) required neurosurgical intervention for hemorrhage progression. CONCLUSION: Patients receiving LMWH were at higher risk for hemorrhage progression. We were unable to demonstrate safety of LMWH for VTE prophylaxis in patients with brain injury. The risk of using LMWH may exceed its benefit. LEVEL OF EVIDENCE: Therapeutic study, level IV.