Characteristics of pathologic complete response for locally advanced rectal cancer.

BACKGROUND: Neoadjuvant chemoradiation (NACRT) is the standard of care for locally advanced rectal cancers. The purpose of this study was to determine patient and tumor factors associated with a pathologic complete response (pCR). METHODS: The National Surgical Quality Improvement Program proctectomy-targeted database was utilized to identify all patients from 2016 to 2020 who underwent NACRT followed by proctectomy with curative intent for T3-4N0-2 rectal cancers. RESULTS: A total of 1891 patients were included, of which 253 (13.4%) demonstrated a pCR. Pretreatment N0 staging was associated with a higher rate of pCR (18.9%) when compared to N1 (6.7%) and N2 (6.7%) (p < 0.0001). Patients clinically staged at T3N0 had the highest rate of pCR (19.5%). Gender, age, race, weight, smoking status, and tumor height were not associated with pCR. CONCLUSIONS: Patients with cN0 disease were more likely to experience a pCR compared to cN1-2 patients. Tumor height relative to anal verge or patient demographics were not associated with pCR.

Cholecystectomy prior to short bowel syndrome does not alter nutritional prognosis.

BACKGROUND: Previous cholecystectomy is common in patients with short bowel syndrome (SBS). An intact gallbladder is beneficial in preventing cirrhosis in SBS patients, but the nutritional consequences of cholecystectomy are largely unknown. Our aim was to evaluate the effect of pre-SBS cholecystectomy on need for chronic parenteral nutrition (PN). METHODS: We reviewed 485 adults with SBS: 267 underwent cholecystectomy prior to SBS and 218 patients had an intact gallbladder. Demographic data, intestinal anatomy, and nutritional outcome were compared. RESULTS: Pre-SBS cholecystectomy patients were more likely to have had postoperative SBS and BMI >35. Intestinal remnant length and anatomy type and performance of surgical rehabilitation procedures within the first year were similar. Overall, there was no significant difference in the need for PN > 1year between the two groups. There was also no significant difference in the need for PN > 1year in any specific subgroup of intestinal remnant length or intestinal anatomy. CONCLUSIONS: Cholecystectomy performed prior to the development of SBS does not influence the nutritional prognosis of SBS, regardless of the intestinal remnant length and anatomy type.

Celiac disease and the surgeon.

BACKGROUND: Celiac disease (CD), a disorder characterized by intestinal inflammation and villus atrophy, has protean manifestations. CD is being diagnosed more frequently but is often undiagnosed when encountered by surgeons. Our aim was to review aspects of CD that are relevant to the surgeon. METHODS: A PubMed database search was performed for articles published between January 2000 and December 2021 related to surgical issues in CD. RESULTS: CD is associated with a variety of conditions throughout the gastrointestinal tract. There is an increased risk of a variety of malignancies, including small intestinal tumors. Patients with CD are at an increased risk for operations for common problems such as appendicitis. Patients with undiagnosed CD undergoing operation may develop symptoms leading to diagnosis postoperatively. CONCLUSION: Surgeons should be aware of CD associated conditions, the risk of malignancy and confounding symptoms. Undiagnosed CD should be suspected if malabsorptive symptoms develop following operation.

The effect of pre-resection obesity on post-resection body composition after 75% small bowel resection in rats.

In patients with short bowel syndrome, an elevated pre-resection Body Mass Index may be protective of post-resection body composition. We hypothesized that rats with diet-induced obesity would lose less lean body mass after undergoing massive small bowel resection compared to non-obese rats. Rats (CD IGS; age = 2 mo; N = 80) were randomly assigned to either a high-fat (obese rats) or a low-fat diet (non-obese rats), and fed ad lib for six months. Each diet group then was randomized to either underwent a 75% distal small bowel resection (massive resection) or small bowel transection with re-anastomosis (sham resection). All rats then were fed ad lib with an intermediate-fat diet (25% of total calories) for two months. Body weight and quantitative magnetic resonance-determined body composition were monitored. Preoperative body weight was 884 ± 95 versus 741 ± 75 g, and preoperative percent body fat was 35.8 ± 3.9 versus 24.9 ± 4.6%; high-fat vs. low fat diet, respectively (p < 0.0001); preoperative diet type had no effect on lean mass. Regarding total body weight, massive resection produced an 18% versus 5% decrease in high-fat versus low-fat rats respectively, while sham resection produced a 2% decrease vs. a 7% increase, respectively (p < 0.0001, preoperative vs. necropsy data). Sham resection had no effect on lean mass; after massive resection, both high-fat and low-fat rats lost lean mass, but these changes were not different between the latter two rat groups. The high-fat diet and low-fat diet induced obesity and marginal obesity, respectively. The massive resection produced greater weight loss in high-fat rats compared to low-fat rats. The type of dietary preconditioning had no effect on lean mass loss after massive resection. A protective effect of pre-existing obesity on lean mass after massive intestinal resection was not demonstrated.

Patient factors influence surgical options in gastroparesis.

BACKGROUND: Patient selection for the diverse surgical procedures for gastroparesis remains poorly defined. Our aim was to evaluate how patient factors have determined our surgical approach to gastroparesis. METHODS: 95 patients undergoing 105 surgical procedures for gastroparesis were reviewed. Patient factors were compared across six surgical procedures: gastric neurostimulator, pyloroplasty, neurostimulator plus pyloroplasty, sleeve gastrectomy, gastric bypass and gastrectomy. Global symptom severity was determined preoperatively and at last follow up. RESULTS: There were significant differences in etiology, BMI and gastroesophageal reflux across the various operations. Patients undergoing pyloroplasty and gastrectomy; were more likely to have a postsurgical etiology. (p < .05) Patients undergoing sleeve gastrectomy and gastric bypass were more likely to have BMI >35. (p <.05) Those undergoing sleeve gastrectomy were less likely to have gastroesophageal reflux preoperatively. (p <.05) There was no difference in preoperative clinical stage across the procedures. CONCLUSION: Patient factors influence choice of procedure in the surgical treatment of gastroparesis. Etiology of gastroparesis, BMI >35 and gastroesophageal reflux are important determinants.

Inflammatory Bowel Disease and Short Bowel Syndrome.

Short bowel syndrome / intestinal failure (SBS/IF) is a rare and debilitating disease process that mandates a multidisciplinary approach in its management. Inflammatory bowel disease (IBD), in particular Crohn's disease (CD), predisposes patients to development of SBS/IF. This review discusses SBS/IF from the perspective of IBD, with an emphasis on prevention and treatment in the setting of CD. The aims of this review are to emphasize the unique treatment goals of the newly diagnosed SBS/IF patient, and highlight the role of both medical and surgical therapies in the management of IBD-related SBS/IF, including intestinal transplantation.

The influence of medical school on career choice: A longitudinal study of students' attitudes toward a career in general surgery.

BACKGROUND: Less than 80% of general surgery (GS) residency positions are filled by graduates from allopathic, U.S. medical schools. The aim of this study was to gauge students' interest in pursuing GS throughout their medical school matriculation and explore students' changing perceptions of the specialty. METHODS: Students at two medical schools were surveyed annually for 4 years. Survey responses regarding interest were compared to actual NRMP match results. RESULTS: Interest in a GS career was highest at the outset of medical school and declined steadily during the program, which was similar at both schools, including a positive effect on interest from the surgical clerkship. CONCLUSIONS: Our findings suggest that experiences during medical school impact students' perceptions of GS; specifically, lifestyle, work environment, and the length of training discouraged pursuit of GS. Perception of a GS's lifestyle and the educational environment are both highly modifiable factors that could increase interest in general surgery amongst graduates.

Prophylactic cholecystectomy in short bowel syndrome: Is it being utilized?

INTRODUCTION: Cholelithiasis is common in patients with short bowel syndrome (SBS). Prophylactic cholecystectomy (PC) of the non-diseased gallbladder has been recommended in SBS patients when laparotomy is being undertaken for other reasons. Our aim was to determine if PC is being utilized. METHODS: 500 adults with SBS were seen over a 25 year period. 215 undergoing cholecystectomy prior to SBS were excluded, leaving 285 patients for evaluation. RESULTS: 151 (53%) SBS patients underwent a subsequent laparotomy. 77 underwent cholecystectomy for cholelithiasis at the 1st opportunity. 27 patients underwent a PC at the 1st opportunity. 47 patients did not undergo PC at the 1st opportunity. 17 (36%) of these 47 patients subsequently developed cholelithiasis with 7 undergoing cholecystectomy. Age, gender, diagnosis and initial BMI and need for longterm parenteral nutrition were similar in patients who had PC or did not. PC patients were more likely to have intestinal remnant length <60 cm (59% vs 21%, p < .05). CONCLUSIONS: Overall 10% of SBS patients underwent PC. However, only 36% of eligible patients undergoing laparotomy had a PC.

Risk of Intestinal Malignancy in Patients With Short Bowel Syndrome.

BACKGROUND: Postresection intestinal adaptation is an augmented self-renewal process that might increase the risk of malignant transformation in the intestine. Furthermore, patients with short bowel syndrome (SBS) have other characteristics that might increase this risk. Our aim was to determine the incidence of new intestinal malignancy in SBS patients. METHODS: We reviewed the records of 500 adult SBS patients identified from 1982-2013. There were 199 men and 301 women ranging in age from 19-91 years. Follow-up from the time of diagnosis of SBS ranged from 12-484 months. A total of 186 (37%) patients were followed >5 years. RESULTS: The cause of SBS was postoperative in 35% of patients, malignancy/radiation in 19%, mesenteric vascular disease in 17%, Crohn's disease in 16%, and other in 13%. Twenty-eight (6%) patients received growth stimulatory medications. Fifteen percent of patients had a prior total colectomy. Twenty-eight (6%) patients underwent intestinal transplantation, and 115 (23%) patients had a previous abdominal malignancy, including colorectal cancer in 43 patients. Thirty-six (7%) received radiation therapy. Recurrent colon cancer was found in 2 patients, one at a stoma and the other with lung metastases. New colon cancer was found in 1 patient (0.2%), a 62-year-old woman with long-standing Crohn's disease. CONCLUSION: The incidence of colon cancer in this heterogenous group of patients with SBS was similar to that of the normal population. This suggests that the risk of developing a new colon cancer in patients with SBS is not increased.

Food cravings and food consumption after Roux-en-Y gastric bypass versus cholecystectomy.

BACKGROUND: Food cravings and consumption of craved foods after Roux-en-Y gastric bypass (RYGB) are poorly understood. Food cravings after bariatric surgery may explain why some patients fail to change eating behaviors after RYGB, and understanding these cravings may provide better information for nutritional counseling to either enhance weight loss or prevent weight regain. OBJECTIVES: To study cravings in RYGB patients and compare them with cholecystectomy (CC) control patients. SETTING: This study took place in a university hospital. METHODS: RYGB patients (n = 50) and CC control patients (n = 38) completed a validated food craving inventory before surgery and at 2 and 6 weeks postoperatively. In addition, RYGB patients completed the food craving inventory at 12, 24, 36, and 52 weeks postoperatively. A linear mixed-effect model with a first-order autoregressive structure for correlations was used to evaluate changes in food consumption and food cravings between visits. Correlations between food cravings and body mass index (BMI) or weight changes before and after RYGB were assessed with Spearman correlation coefficients. P<.05 was considered statistically significant. RESULTS: After RYGB, food consumption decreased significantly compared with CC control patients and was lowest at 2 weeks. Consumption progressively increased over time in the first year but remained significantly less than that from presurgery. In addition, a higher preoperative BMI was found to correlate moderately with higher preoperative cravings of the total of all 4 food groups studied (r = .3, P = .04); high-fat foods (r = .3, P = .04); and sweets (r = .3, P = .03). However, with the exception of preoperative cravings for high-fat foods, these scores were not predictive of changes in BMI after surgery. Overall, RYGB did not significantly affect food cravings after surgery compared with CC control patients. CONCLUSION: These findings indicate that RYGB may limit food consumption but does not affect the drive to consume certain types of food. Because food cravings are high in patients with obesity before surgery and remain high after surgery, these findings suggest a possible reason for noncompliance with dietary recommendations after RYGB.

Trends in the match rate and composition of candidates matching into categorical general surgery residency positions in the United States.

BACKGROUND: The aim of this study was to analyze the trends in the proportion of students from various educational backgrounds who matched into categorical general surgery (GS) residency positions. METHODS: National Resident Matching Program reports (1994 to 2014) were analyzed, and regression was used to estimate the trends for each group. RESULTS: The match rate into GS-categorical residency has remained stable; however, since 1994, we witnessed a 13% decrease in US seniors matching into GS. This has corresponded to proportional increases in matches for US citizens from international medical schools (US IMG, 1350%) and a 62% increase for non-US citizen international medical graduates (non-US IMG) into GS. In comparison, US IMG matches into all first-year postgraduate positions increased by 468%, whereas non-US IMG matches decreased by 15%. CONCLUSIONS: The stable match rates into categorical GS residencies are not because of US seniors but rather because of a rise in the number of IMGs. In contrast to the decreased reliance on non-US IMGs in all other specialties, GS is accepting a larger proportion of non-US IMGs.

Transanal endoscopic microsurgery and transanal minimally invasive surgery: is one technique superior?

BACKGROUND: Transanal endoscopic microsurgery (TEM) and transanal minimally invasive surgery (TAMIS) have been shown to improve the quality of transanal resections, allowing for improved visibility and access to the proximal rectum. This study compares the short-term outcomes between TEM and TAMIS among experienced colorectal surgeons. METHOD: A retrospective review was conducted for TEM and TAMIS performed from 2012 to 2015 by local colorectal surgeons. Baseline patient demographics, operative variables, pathology results, and short-term outcomes were assessed. RESULTS: Sixty-nine patients were identified (40 TEM and 29 TAMIS). Patient demographics, tumor characteristics, operative variables, margin status, and postoperative complications were similar for both. Volume of resection was higher for TAMIS (P < .001). Lymph node retrieval was achieved in 17.2% of TAMIS cases compared with 0% of TEM (P = .01). CONCLUSIONS: TAMIS appears to have equivalent indications and outcomes compared with TEM. TAMIS is associated with larger specimens and more frequent presence of mesorectal lymph nodes.

Cholecystectomy and Liver Disease in Short Bowel Syndrome.

BACKGROUND: Recently, an association has been proposed between cholecystectomy and various liver diseases. Our aim was to determine whether cholecystectomy in short bowel patients influences the risk of liver disease. METHODS: We reviewed 422 adults: 182 underwent cholecystectomy prior to short bowel, 102 after developing short bowel, and 138 patients still had the gallbladder in place. RESULTS: Compared to pre and post short bowel, gallbladder patients were significantly less likely to have obesity (18 % and 21 % vs 9 %), central line infections (59 % and 69 % vs 46 %), intestine <60 cm (30 % and 39 % vs 26 %), and require parenteral nutrition >1 year (72 % and 77 % vs 64 %). The incidence of fatty liver was similar (31, 26, and 25 %). Fibrosis/cirrhosis was less common in the gallbladder group (26 % and 36 % vs 16 %). Frequency of end-stage liver disease was similar (15, 22, and 11 %). On multivariate analysis, cholecystectomy, parenteral nutrition >1 year, line infection, and intestine <60 cm were predictors of fibrosis/cirrhosis. Parenteral nutrition >1 year, line infection, and intestine <60 cm were predictors of end-stage liver disease. CONCLUSIONS: Cholecystectomy does not appear to increase the incidence of liver disease in short bowel patients overall. Fibrosis/cirrhosis occurs significantly less frequently in patients with an intact gallbladder.

Effect of proximal versus distal 50% enterectomy on nutritional parameters in rats preconditioned with a high-fat diet or regular chow.

Obesity may protect against the nutritional consequences of short bowel syndrome. We hypothesized that rats preconditioned with an obesogenic diet would have better outcomes after surgical induction of short bowel syndrome compared to rats on regular chow. Rats were fed a high-fat diet or regular rat chow for six months, and then underwent 50% proximal, 50% distal, or sham enterectomy. Food intake, weight, and body composition were monitored before and for 4 weeks after surgery. The high-fat diet consistently produced obesity (>25% body fat). All procedures induced weight loss, but there was no discernable difference between resection vs. sham resection. Rats on the high-fat diet had a greater post-resection loss of body fat compared to rats on chow (36 vs. 26 g, respectively). There was a nonsignificant trend of less lean mass loss in the former compared to the latter rats (16 vs. 33 g, respectively). Enterectomy moderated serum ghrelin, GIP, PPY, insulin, and leptin. Intestinal adaptation was not different between obese vs. non-obese rats. Rats preconditioned with the high-fat diet may have had better retention of lean body mass after a surgical procedure compared to rats on chow. The effect of 50% enterectomy was less than expected.

Surgical aspects of celiac disease.

Celiac disease, characterized by intestinal inflammation and malabsorption, occurs in 1 per cent of the population and is often undiagnosed. These patients are at increased risk for surgical procedures resulting from symptoms, associated intestinal disorders, and malignancy. Our aim was to determine the incidence and outcome of abdominal operations in patients with celiac disease. Records of 512 adult patients with celiac disease evaluated over a 22-year period were reviewed. Operations were classified as related or unrelated to celiac disease. One hundred eighty-eight (36%) of 512 patients underwent abdominal operations. One hundred twenty-seven (68%) of the 188 patients had unrelated procedures. Sixty-one (32%) had operations considered related to celiac disease. Twenty-six (43%) of 61 with related procedures were diagnosed preoperatively. Procedures were performed for pain, obstruction, motility disorders, and malignancy. Six patients had recurrent pancreatitis. Seven patients underwent liver transplantation. Thirty-five (57%) related procedures led to the diagnosis of celiac disease including "unmasking" (n = 25) and diagnostic findings (n = 10). One-third of patients with celiac disease undergo abdominal operations of which one-third are related to celiac disease. Operations are related to complications of celiac disease and often lead to the initial diagnosis.

Radiographic findings following irrigation of chronic perineal drain with hydrogen peroxide.

INTRODUCTION: Hydrogen peroxide is a widely available agent used for irrigation and disinfecting. With misuse, significant side effects have been noted ranging from nausea to abdominal cramping to portal venous gas, air embolism and death. PRESENTATION OF CASE: We present an 81 year old male who developed a rectovesicular fistula following radiation for metastatic prostate cancer. He had recurrent bleeding and infections and underwent a pelvic exenteration which was complicated by a persistent pelvic abscess requiring placement of a transperineal drainage catheter. After months of persistent drainage, he noted decreased output and irrigated the catheter with 3% hydrogen peroxide. He presented to the emergency room with fever, diarrhea and abdominal cramping but no rebound or guarding. CT depicted free air in the pre-sacral space extending into the retroperitoneum and diffusely throughout the peritoneum. Given his clinical exam and upon review of imaging, we assumed his radiographic findings were related to the direct instillation of hydrogen peroxide into his chronic pelvic cavity. DISCUSSION: Hydrogen peroxide has been used therapeutically for over 100 years. Hydrogen peroxide exerts direct cytotoxicity by corrosion and lipid peroxidation and indirectly by oxygen gas formation. When the oxygen produced exceeds the solubility in the blood, arterial and venous gas embolism occur. It is this sequelae of hydrogen peroxide that is described most frequently in the literature. CONCLUSION: Instillation of hydrogen peroxide into a chronic pelvic cavity resulted in a benign pneumoperitoneum. This effect of hydrogen peroxide is a significant and potentially treatment altering radiographic finding.

Short bowel syndrome after laparoscopic procedures.

Short bowel syndrome (SBS) is a potential postoperative complication after intra-abdominal procedures. Whether the laparoscopic approach is as likely to result in SBS or the causative mechanisms are similar to open procedures is unknown. Our aim was to evaluate potential mechanisms of SBS after laparoscopic procedures. The records of 175 adult patients developing SBS as a postoperative complication were reviewed. One hundred forty-seven patients had open procedures and 28 laparoscopic. Colectomy (39%), hysterectomy (11%), and appendectomy (11%) were the most common open procedures. SBS followed laparoscopic gastric bypass (46%) and cholecystectomy (32%) most frequently. The mechanisms of SBS were different: adhesive obstruction (57 vs 22%, P < 0.05) was more common in the open group, whereas volvulus (18 vs 46%, P < 0.05) was more common after laparoscopy. Overall, ischemia (25 vs 32%) was similar but significantly more laparoscopic patients had postoperative hypoperfusion (32 vs 67%, P < 0.05). Eleven of the 13 laparoscopic bariatric procedures had internal hernias and volvulus. Of the nine patients undergoing cholecystectomy, four developed ischemia early postoperatively presumably secondary to pneumoperitoneum. SBS is an increasingly recognized complication of laparoscopic procedures. The mechanisms of intestinal injury differ from open procedures with a higher incidence of volvulus and more frequent ischemia from hypoperfusion.

Pre-resection gastric bypass reduces post-resection body mass index but not liver disease in short bowel syndrome.

BACKGROUND: Obese patients developing short bowel syndrome (SBS) maintain a higher body mass index (BMI) and have increased risk of hepatobiliary complications. Our aim was to determine the effect of pre-resection gastric bypass (GBP) on SBS outcome. METHODS: We reviewed 136 adults with SBS: 69 patients with initial BMI < 35 were controls; 43 patients with BMI > 35 were the obese group; and 24 patients had undergone GBP before SBS. RESULTS: BMI at 1, 2, and 5 years was similar in control and GBP groups, whereas obese patients had a persistently increased BMI. Eight (33%) of the GBP patients had a pre-resection BMI > 35, but post-SBS BMI was similar to those <35. Obese patients were more likely to wean off PN (47% vs 20% control and 12% GBP, P < .05). Radiographic fatty liver tended to be higher in the GBP group (54% vs 19% control and 35% obese). End-stage liver disease occurred more frequently in obese and GBP patients (30% and 33% vs 13%, P < .05). CONCLUSIONS: Pre-resection GBP prevents the nutritional benefits of obesity but does not eliminate the increased risk of hepatobiliary disease in obese SBS patients. This occurs independent of pre-SBS BMI suggesting the importance of GBP itself or history of obesity rather than weight loss.