Stimulatory Anticancer Effect of Resveratrol Mediated by G Protein-Coupled Estrogen Receptor in Colorectal Cancer

Colorectal cancer (CRC) is one of the most high-risk cancers; however, it has been suggested that estrogen signaling in CRC could have a protective effect. Therefore, we focused on the function of the G protein-coupled estrogen receptor (GPER) among the estrogen receptors in CRC. In this study, we investigated the therapeutic effect of resveratrol via GPER in CRC (RKO and WiDr) cells, CRC cell-derived xenograft models, and organoids (30T and 33T). Resveratrol significantly suppressed cell viability and proliferation in highly GPER-expressing RKO cells compared to that in low GPER-expressing WiDr cells. In xenograft models, resveratrol also delayed tumor growth and exhibited a high survival rate depending on GPER expression in RKO-derived tumors.Furthermore, resveratrol significantly inhibited the viability of organoids with high GPER expression. Additionally, the anticancer effect of resveratrol on CRC showed that resveratrol rapidly responded to GPER, while increasing the expression of p-ERK and Bax and cleaving PARP proteins.

Clinical outcomes of locking polymeric clip for laparoscopic appendectomy in patients with appendicitis: a retrospective comparison with loop ligature

Purpose@#This study aimed to compare the clinical outcomes of laparoscopic appendectomy (LA) according to the method of appendiceal stump closure. @*Methods@#Patients who underwent LA for appendicitis between 2010 and 2020 were retrospectively reviewed. Patients were classified into locking polymeric clip (LPC) and loop ligature (LL) groups. Clinical outcomes were compared between the groups. @*Results@#LPC and LL were used in 188 (56.6%) and 144 patients (43.4%), respectively for appendiceal stump closure. No significant differences were observed in sex, age, comorbidities, and the severity of appendicitis between the groups. The median operative time was shorter in the LPC group than in the LL group (64.5 minutes vs. 71.5 minutes, P=0.027). The median hospital stay was longer in the LL group than in the LPC group (4 days vs. 3 days, P=0.020). Postoperative incidences of intraabdominal abscess and ileus were higher in the LL group than in the LPC group (4.2% vs. 1.1%, P=0.082 and 2.8% vs. 0%, P=0.035; respectively). The readmission rate was higher in the LL group than that in the LPC group (6.3% vs. 1.1%, P=0.012). @*Conclusion@#Using LPC for appendiceal stump closure during LA for appendicitis was associated with lower postoperative complication rate, shorter operative time, and shorter hospital stay compared to the use of LL. Operative time above 60 minutes and the use of LL were identified as independent risk factors for postoperative complications in LA. Therefore, LPC could be considered a more favorable closure method than LL during LA for appendicitis.

The Impact of Primary Tumor Resection on Survival in Asymptomatic Colorectal Cancer Patients With Unresectable Metastases

Purpose@#This study was conducted to evaluate the effectiveness of primary tumor resection (PTR) in asymptomatic colorectal cancer (CRC) patients with unresectable metastases using the inverse probability of treatment weighting (IPTW) method to minimize selection bias. @*Methods@#We selected 146 patients diagnosed with stage IV CRC with unresectable metastasis between 2001 and 2018 from our institutional database. In a multivariate logistic regression model using the patients’ baseline covariates associated with PTR, we applied the IPTW method based on a propensity score and performed a weighted Cox proportional regression analysis to estimate survival according to PTR. @*Results@#Upfront PTR was performed in 98 patients, and no significant differences in baseline factors were detected. The upweighted median survival of the PTR group was 18 months and that of the non-PTR group was 15 months (P = 0.15). After applying the IPTW, the PTR was still insignificant in the univariate Cox regression (hazard ratio [HR], 0.26; 95% confidence interval [CI], 0.5–1.21). However, in the multivariate weighted Cox regression with adjustment for other covariates, the PTR showed a significantly decreased risk of cancer-related death (HR, 0.61; 95% CI, 0.40–0.94). @*Conclusion@#In this study, we showed that asymptomatic CRC patients with unresectable metastases could gain a survival benefit from upfront PTR by analysis with the IPTW method. However, randomized controlled trials are mandatory.

Neutrophil to Lymphocyte Ratio: A Predictive Marker for Treatment Outcomes in Patients With Rectal Cancer Who Underwent Neoadjuvant Chemoradiation Followed by Surgery

PURPOSE: In this study, we investigated the role of neutrophil to lymphocyte ratio (NLR) as a predictor of tumor response and as a prognostic factor in patients with rectal cancer who had undergone curative surgery after neoadjuvant chemoradiation therapy (nCRT). METHODS: Between January 2009 and July 2016, we collected 140 consecutive patients who had undergone curative intent surgery after nCRT due to rectal adenocarcinoma. We obtained the pre- and post-nCRT NLR by dividing the neutrophil count by the lymphocyte count. The cutoff value was obtained using receiver operating characteristic analysis for tumor response and using maximally selected rank analysis for recurrence-free survival (RFS). The relationship among NLR, tumor response, and RFS was assessed by adjusting the possible clinico-pathological confounding factors. RESULTS: The possibility of pathologic complete response (pCR) was significantly decreased in high pre- (>2.77) and postnCRT NLR (>3.23) in univariate regression analysis. In multivariate analysis, high post-nCRT NLR was an independent negative predictive factor for pCR (adjusted odds ratio, 0.365; 95% confidence interval [CI], 0.145–0.918). The 5-year RFS of all patients was 74.6% during the median 37 months of follow-up. Patients with higher pre- (>2.66) and post-nCRT NLR (>5.21) showed lower 5-year RFS rates (53.1 vs. 83.3%, P = 0.006) (69.2 vs. 75.7%, P = 0.054). In multivariate Cox analysis, high pre-nCRT NLR was an independent poor prognostic factor for RFS (adjusted hazard ratio, 2.300; 95% CI, 1.061–4.985). CONCLUSION: Elevated NLR was a negative predictive marker for pCR and was independently associated with decreased RFS. For confirmation, a large-scale study with appropriate controls is needed.

Is the Location of the Tumor Another Prognostic Factor for Patients With Colon Cancer?

PURPOSE: In this study, we investigated both the characteristics of right colon cancer (RTCC) in comparison with those of left colon cancer (LTCC) and the impact of the location of the colon cancer on the prognosis. METHODS: We retrospectively analyzed the cases of 974 patients with nonmetastatic colon cancer who had undergone surgery with a curative intent from January 2001 to December 2011. RTCC was defined as a tumor located proximal to the splenic flexure. The characteristics of RTCC cancer were investigated by using descriptive analyses, and their impacts on the prognosis were assessed by using a Cox multivariate regression. RESULTS: Compared to LTCC, RTCC showed a female-dominant feature, and an undifferentiated pathology was more frequently observed. The number of lymph nodes retrieved from patients with RTCC was significantly higher than that retrieved from patients with LTCC. During 75 months of follow-up, peritoneal recurrence was more common in patients with RTCC than it was in patients with LTCC, and among the patients with stage III colon cancer, the disease-free and the overall survival rates were significantly worse in patients with RTCC. After adjustments with the other prognostic factors associated with colon cancer had been made, a tumor located at the right colon was found to be independently associated with poor prognosis. CONCLUSION: RTCC showed unique clinicopathologic features and was associated with a poorer prognosis.

Is Microsatellite Instability Really a Good Prognostic Factor of Colorectal Cancer?

PURPOSE: The aim of this study was to investigate the clinicopathologic features of and the prognosis for colorectal cancers (CRCs) with microsatellite instabilities (MSIs). METHODS: Between 2006 and 2009, genotyping was performed on 245 patients with stage II/III CRCs to establish the MSI status. The clinicopathologic differences and the prognostic value of MSI were analyzed. The median follow-up period was 38 months (range, 7-68 months). RESULTS: Of the total 245 patients, 20 (8.2%) had MSI-high (H) and 225 (91.8%) had MSI-low (L) or stable (S) CRCs. Adjuvant chemotherapies were performed on 101 stage II (87.8%) and 107 stage III patients (82.3%). Patients with MSI-H CRCs more frequently had a family history of colon cancer (10% vs. 2.7%, P = 0.003), more frequently had a cancer located at the proximal colon (90.0% vs. 19.1%, P < 0.0001), and more often showed a mucinous phenotype or poor differentiation (35.0% vs. 7.1%, P = 0.001). Despite less frequent lymph node metastasis (25% vs. 55.6%, P = 0.01), the number of retrieved lymph nodes was higher (26.3 +/- 13.1 vs. 20.7 +/- 1.2, P = 0.04) in the MSI-H group. The overall survival and the disease-free survival (DFS) did not differ with respect to MSI status. However, in the stage II subgroup, the DFS for patients with MSI-H CRCs was significantly worse (72.2% vs. 90.7%, P = 0.03). The multivariate analysis performed on this subgroup revealed that MSI-H was an independent poor prognostic factor (adjusted hazard ratio, 4.0; 95% confidence interval, 1.0-15.6, P = 0.046). CONCLUSION: MSI-H CRCs had distinct clinicopathologic features, and MSI-H was an independent poor prognostic factor in stage II CRCs. Considering the majority of stage II patients were administrated adjuvant chemotherapy, the efficacy of adjuvant chemotherapy for treating MSI CRCs might be different from that for treating MSI-L/S tumors.

Role of Peritoneal Lavage Cytology and Prediction of Prognosis and Peritoneal Recurrence After Curative Surgery for Colorectal Cancer

PURPOSE: In colorectal cancer, the role of detecting free malignant cells from peritoneal lavage is currently unclear. In this study, we investigated the positive rate of free malignant cells in peritoneal lavage fluid and their predictive value for prognosis and peritoneal recurrence after a curative resection. METHODS: From October 2009 to December 2011, in a prospective manner, we performed cytologic examinations of peritoneal lavage fluid obtained just after the abdominal incision from 145 patients who underwent curative surgery for colorectal cancer. We used proportional hazard regression models to analyze the predictive role of positive cytology for peritoneal recurrence and survival. RESULTS: Among total 145 patients, six patients (4.1%) showed positive cytology. During the median follow-up of 32 months (range, 8-49 months), 27 patients (18.6%) developed recurrence. Among them, 5 patients (3.4%) showed peritoneal carcinomatosis. In the multivariate analysis, positive cytology was an independent predictive factor for peritoneal recurrence (hazard ratio [HR], 136.5; 95% confidence interval [CI], 12.2-1,531.9; P < 0.0001) and an independent poor prognostic factor for overall survival (HR, 11.4; 95% CI, 1.8-72.0; P = 0.009) and for disease-free survival (HR, 11.1; 95% CI, 3.4-35.8; P < 0.0001). CONCLUSION: Positive cytology of peritoneal fluid was significantly associated with peritoneal recurrence and worse survival in patients undergoing curative surgery for colorectal cancer. Peritoneal cytology might be a useful tool for selecting patients who need intraperitoneal or systemic chemotherapy.

Immunogenicity of Influenza Vaccine in Colorectal Cancer Patients / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Although influenza is regarded as a major cause of morbidity and mortality in immunocompromised patients, vaccine coverage remains poor. We evaluated the immunogenicity of influenza vaccines in colorectal cancer patients. MATERIALS AND METHODS: In this study, 40 colorectal cancer patients who received an influenza vaccine at the Korea Cancer Center Hospital during the 2009-2010 and 2010-2011 influenza seasons were analyzed. The blood samples were collected at prevaccination and 30 days post vaccination, and antibody titers were measured using the hemagglutination-inhibition tests. RESULTS: In the 2009-2011 season, the seroprotection rate for H1N1 (94.7%) was significantly higher than that for H3N2 (42.1%) and B (47.3%). The seroconversion rate was 52.6%, 26.3%, and 36.8% for H1N1, H3N2, and B, respectively. Fold increase of geometric mean titer (MFI) was 3.86, 1.49, and 3.33 for H1N1, H3N2, and B, respectively. In the 2010-2011 season, the seroprotection rate for H1N1 (57.1%) was significantly higher than that for H3N2 (52.4%) and B (38.1%). The seroconversion rate was 52.4%, 47.6% and 33.3% for H1N1, H3N2, and B, respectively. MFI was 12.29, 3.62 and 4.27 for H1N1, H3N2, and B, respectively. CONCLUSION: Our study cohort showed an acceptable immune response to an influenza vaccine without significant adverse effects, supporting the recommendation for annual influenza vaccination in colorectal cancer patients.

Incidence and Risk Factors of Parastomal Hernia

PURPOSE: Among the various stoma complications, the parastomal hernia (PSH) is the most common. Prevention of PSH is very important to improve the quality of life and to prevent further serious complications. The aim of this study was to analyze the incidence and the risk factors of PSH. METHODS: From January 2002 and October 2008, we retrospectively reviewed 165 patients who underwent an end colostomy. As a routine oncologic follow-up, abdomino-pelvic computed tomography was used to examine the occurrence of the PSH. The associations of age, sex, body mass index (BMI), history of steroid use and comorbidities to the development of the PSH were analyzed. The median duration of the follow-up was 36 months (0 to 99 months). RESULTS: During follow-up, 50 patients developed a PSH and the 5-year cumulative incidence rate of a PSH, obtained by using the Kaplan-Meier method, was 37.8%. In the multivariate COX analysis, female gender (hazard ratio [HR], 3.29; 95% confidence interval [CI], 1.77 to 6.11; P < 0.0001), age over 60 years (HR, 2.37; 95% CI, 1.26 to 4.46; P = 0.01), BMI more than 25 kg/m2 (HR, 1.8; 95% CI, 1.02 to 3.16; P = 0.04), and hypertension (HR, 2.08; 95% CI, 1.14 to 3.81; P = 0.02) were all independent risk factors for the development of a PSH. CONCLUSION: The 5-year incidence rate of a PSH was 37.8%. The significant risk factors of a PSH were as follows: female gender, age over 60 years, BMI more than 25 kg/m2, and hypertension. Using a prophylactic mesh during colostomy formation might be advisable when the patients have these factors.

Impact on Prognosis of Lymph Node Micrometastasis and Isolated Tumor Cells in Stage II Colorectal Cancer

PURPOSE: Even though the importance of micrometastases (MMS) and isolated tumor cells (ITC) has been brought up by many physicians, its impact on the prognosis in stage II colorectal cancer is uncertain. In this research, we tried to investigate the clinical features of MMS and ITC and to prove any correlation with prognosis. METHODS: The research pool was 124 colorectal cancer patients who underwent a curative resection from April 2005 to November 2009. A total of 2,379 lymph nodes (LNs) were examined, and all retrieved LNs were evaluated by immunohistochemical staining with anti-cytokeratin antibody panel. Clinicopathologic parameters and survival rates were compared based on the presence of MMS or ITC and on the micrometastatic lymph node ratio (mmLNR), which is defined as the number of micrometastatic LNs divided by the number of retrieved LNs. RESULTS: Out of 124 patients (26.6%) 33 were found to have MMS or ITC. There were no significant differences in clinicopathologic features, such as gender, tumor location and size, depth of invasion, histologic grade, except for age (P = 0.04). The three-year disease-free survival rate for the MMS or ITC positive group was 85.7%, and that for MMS and ITC negative group was 92.8% (P = 0.209). The three-year disease-free survival rate for the mmLNR > 0.25 group was 73.3%, and that for the mmLNR < or = 0.25 group was 92.9% (P = 0.03). CONCLUSION: The presence of MMS or ITC was not closely correlated to the prognosis. However, mmLNR is thought to be a valuable marker of prognosis in cases of stage II colorectal cancer.

Effectiveness of Adjuvant Chemotherapy with 5-FU/Leucovorin and Prognosis in Stage II Colon Cancer

PURPOSE: The aims of this study were to investigate the survival results and the prognostic factors of adjuvant chemotherapy in stage II colon cancer in the sparsity of Korean data. METHODS: From 1993 to 2006, 363 curatively resected pathologic stage II colon cancer patients were enrolled. Six cycles of adjuvant chemotherapy was performed: intravenous bolus 5-fluorouracil (5-FU) 500 mg/m2 with leucovorin 20 mg/m2 for 2 hours daily for 5 days, followed by a 3-week resting period (n = 308). Fifty-five patients received only curative surgery. A high risk of recurrence was defined as the presence of one or more of the following factors: T4 tumor, lympho-vascular invasion, perineural invasion, perforation, obstruction, retrieved lymph node < 12, and poorly differention. The median follow-up period was 68 months (1 to 205 months). RESULTS: The five-year overall survival (OS) rate was 90.1%, and the five-year disease-free survival (DFS) rate was 84.7%. Among high-risk patients, the OS and the DFS rates of the treatment group were significantly higher than those of the non-treatment group (OS: 90.6% vs. 69.1%, P < 0.0001; DFS: 85.9% vs. 54.1%, P < 0.0001). Among low-risk patients, the survival results of the treatment group were also significantly superior (OS: 97.7% vs. 88.2%, P < 0.0001; DFS: 93.0% vs. 80.0%, P = 0.001). In the multivariate analysis, adjuvant chemotherapy was a significantly favorable prognostic factor for overall survival (hazard ratio, 0.41; 95% confidence interval, 0.22 to 0.75; P = 0.004). CONCLUSION: In our population, adjuvant chemotherapy showed superior survival to curative surgery alone and significantly reduced the risk of death. A nationwide multicenter randomized trial is needed.

Clinicopathologic Characteristics, Surgical Treatment and Outcomes for Splenic Flexure Colon Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This current study examined the clinicopathologic characteristics of patients with splenic flexure (SF) colon cancer and the association with the surgical outcomes to find the optimal procedure to treat this malady. MATERIALS AND METHODS: A total of 167 operated patients with SF colon cancer were consecutively recruited between 1993 and 2003. The clinicopathological, operative and survival data was reviewed and analyzed. RESULTS: For the SF colon cancer patients, the proportion of males was higher than that for the right-sided colon patients or the sigmoid-descending junction & sigmoid (SD & S) colon patients (p or =60 years) and a N1-2 and M1 status were the independent risk factors for overall survival. CONCLUSION: The SF colon cancers exhibited exclusively different characteristics as compared to colon cancers at other site colon cancers. It appears that left hemicolectomy was generally sufficient for a satisfactory oncological outcome, obviating concurrent splenectomy.

Malignancy Associated with Inflammatory Bowel Disease

PURPOSE: As the number of patients with inflammatory bowel disease (IBD) has steadily increased in Korea, IBD-associated cancers are expected to increase in number. This study investigated the clinical features of intestinal cancer in patients with IBD. METHODS: One hundred five patients with ulcerative colitis (UC) and 270 patients with Crohn's disease (CD) under the care of the Department of Colon and Rectal Surgery, Asan Medical Center, between December 1989 and January 2009 were reviewed retrospectively. RESULTS: Ten patients of the 105 with UC and 5 patients of the 270 with CD were found to have intestinal cancer. The mean age was 45 yr (+/-8.8), and the mean duration of IBD at the time of diagnosis of the cancer was 12.6 yr (+/-6.0). Six of the 15 cancer patients had no history of treatment for IBD of more than 3 mo before diagnosis of the cancer. Eleven cancers were located in the rectum (7 in UC, 4 in CD), including 1 case of synchronous cancer. One case of small bowel cancer was found in a patient with small bowel CD. Four cases involved a mucinous adenocarcinoma. Eight of the 12 cases of an adenocarcinoma of the colon and rectum were advanced stage. CONCLUSION: IBD-associated intestinal cancers were found at a relatively young age, were diagnosed at an advanced stage, and had a higher proportion of mucinous adenocarcinomas than in sporadic cancer. Considering the increasing incidence of IBD and the expected increase in the number of IBD-associated cancer in Korea, every effort should be made to prevent intestinal cancer in patients with IBD and to detect it early.

Prognosis and Recurrent Patterns of Sporadic Primary Colon Cancers According to Location

PURPOSE: We aimed to compare the prognosis and the recurrence patterns of sporadic primary colon cancers according to the location of the cancer. METHODS: One thousand four-hundred eighty-three (1,483) stage II, III colon cancer patients who had undergone a consecutive curative resection between January 1989 and December 2003 were analyzed. Hereditary, synchronous, metachronous, and recurrent colon cancers were excluded. The right colon was defined as being from the cecum to the transverse colon, and the left colon was defined as being from the splenic flexure colon to the rectosigmoid colon. The median follow-up time was 63 (3-228) mo. RESULTS: Poorly differentiated and mucinous cell type tumors were more frequent in the right colon. T3 tumors were more frequent in the right colon. Lymph-node-positive tumors were more frequent in the left colon. The recurrence rate was higher in the left colon, but the patterns of recurrence were not different according to the tumor's location. By univariate analysis, age, preoperative serum CEA level, T-stage, N-stage, lymphovascular invasion, postoperative chemotherapy, and tumor location were significant prognostic factors associated with recurrence. By multivariate analysis, sex, preoperative serum CEA level, T-stage, N-stage, postoperative chemotherapy, and tumor location were significant prognostic factors associated with recurrence. The 5-yr disease-free survival rates were 84.0% for right colon cancer and 77.1% for left colon cancer (P=0.005). The recurrence rates for cancers in the sigmoid colon and the rectosigmoid colon were higher than those for cancers in the cecum and the ascending colon. CONCLUSION: The tumor's location was an independent prognostic factor for recurrence, but the pattern of recurrence did not vary with the tumor's location.

Pathologic Complete Remission after Preoperative Chemoradiation for Rectal Cancer: Analysis of Clinicopathologic Characteristics and Oncologic Outcome

PURPOSE: To assess the clinico-pathologic characteristics associated with pathologic complete remission (pCR) after preoperative chemoradiotherapy (PCRT) for rectal cancer and evaluate predictive factors for pCR and prognostic impact of pCR. METHODS: We analyzed 325 patients who underwent PCRT and surgical resection between September 1999 and September 2006. We have treated 319 patients with PCRT for locally advanced rectal cancer and 6 patients for sphincter-saving procedure. Chemotherapy consisted of either of bolus 5-FU (325 mg/m2/d) or capecitabine (1,650 mg/m2/d) for the duration of radiation and after surgery. Radiation therapy was delivered and surgery was performed 4~6 weeks following the completion of PCRT. We compared pCR patients with non-pCR patients according to the clinico-pathologic characteristics and followed up with a median of 32 (range, 12~91) months. RESULTS: The pCR (n=41, 12.6%) and non-pCR (n=284) groups were comparable in age, sex, location of the tumor, chemotherapy regimen, pre-CRT CEA level except pre-CRT clinical stage (12.2% vs. 0.4% in stage I, P= 0.047). There was no significant difference in genetic characteristics between groups. There was no specific predictive factors for pCR except pre-CRT T category (pCR in T2 (5/8, 62.5%) vs. T3 (33/283, 11.7%) or T4 (3/33, 9.1%), P=0.001). The 3-year disease free survival (DFS) was 100% and 83.6% in the pCR and non-pCR group respectively (P=0.012). There were 5 local and 34 systemic recurrences only in non-pCR group. CONCLUSIONS: Rectal cancer patients with pCR after PCRT have an excellent prognosis and are unlikely to fail locally or systemically because of the effect of stage. However there was no specific predictive factor for pCR except preoperative T category.

Risk Factors of Pouch Failure after a Restorative Proctocolectomy

PURPOSE: The aim of this study was to analyze the risk factors of pouch failure after a restorative proctocolectomy. METHODS: A restorative proctocolectomy was performed in 169 patients between November 1989 and May 2007. A retrospective review was done for postoperative complications and follow-up results of pouch failure, and the risk factors of pouch failure were analyzed. Pouch failure was defined as having occurred when a permanent ileostomy was constructed, regardless of pouch removal. The median follow-up was 48 (3~155) months. RESULTS: Among the 169 cases, 86 cases involved ulcerative colitis (UC group), 70 cases involved familial adenomatous polyposis or attenuated adenomatous polyposis coli (FAP group), and the remaining 13 involved hereditary nonpolyposis colorectal cancer or synchronous colon and rectal caner (CRC group). The sex ratios and the incidences of comorbidity were not significantly different between the groups, but the mean ages were. Complications occurred in 61 patients (36.1%): pelvic sepsis (28 cases), pouchitis (23 cases), desmoid tumor (12 cases), wound infection (10 cases), and anastomosis stricture (4 cases). The 5-year cumulative rate of pouch failure was 9.8%. Presence of a desmoid tumor, pelvic sepsis, and anastomosis stricture were risk factors of pouch failure. CONCLUSIONS: The cumulative pouch failure rate after a restorative proctocolectomy was 9.8% for 5 years, and pouch failure was associated with the presence of a desmoid tumor, pelvic sepsis, and anastomosis stricture.

Thrombotic Thrombocytopenic Purpura that Developed after Rectal Cancer Surgery

Thrombotic thrombocytopenic purpura (TTP) in the acute postoperative setting is a syndrome that presents with various symptoms such as microangiopathic hemolytic anemia, thrombocytopenia, fever, renal failure, and change of the patient's mental status. Though most of the previous reports of postoperative TTP have been in conjunction with cardiac or vascular surgery, it has also been reported following orthopedic and abdominal surgeries. We present here a case of a 78 year-old female who was diagnosed with rectal cancer and who developed TTP the 2nd day following her cancer surgery. Because the presentation can be confused with other early postoperative complications, TTP should be considered in the differential diagnosis of the patient who develops unexplained anemia and thrombocytopenia following an abdominal surgery. Awareness of this syndrome is essential because starting plasmapheresis early can be life-saving.