Nomogram for predicting the overall survival of underweight patients with colorectal cancer: a clinical study

BACKGROUND

An underweight individual is defined as one whose Body Mass Index (BMI) is < 18.5 kg/m². Currently, the prognosis in patients with colorectal cancer (CRC) who are also underweight is unclear.

METHODS

Information on South Korean patients who underwent curative resection for CRC without distant metastasis was collected from health insurance registry data between January 2014 and December 2016. We compared the overall survival (OS) of underweight and non-underweight (BMI ≥ 18.5 kg/m²) patients after adjusting for confounders using propensity score matching. A nomogram to predict OS in the underweight group was constructed using the significant risk factors identified in multivariate analysis. The predictive and discriminative capabilities of the nomogram for predicting 3- and 5-year OS in the underweight group were validated and compared with those of the tumor, node, and metastasis (TNM) staging system in the training and validation sets.

RESULTS

A total of 23,803 (93.6%) and 1,644 (6.4%) patients were assigned to the non-underweight and underweight groups, respectively. OS was significantly worse in the underweight group than in the non-underweight group for each pathological stage (non-underweight vs. underweight: stage I, 90.1% vs. 77.1%; stage IIA, 85.3% vs. 67.3%; stage IIB/C, 74.9% vs. 52.1%; and stage III, 73.2% vs. 59.4%, P < 0.001). The calibration plots demonstrated that the nomogram exhibited satisfactory consistency with the actual results. The concordance index (C-index) and area under the receiver operating characteristic curve (AUC) of the nomogram exhibited better discriminatory capability than those of the TNM staging system (C-index, nomogram versus TNM staging system: training set, 0.713 versus 0.564, P < 0.001; validation set, 0.691 versus 0.548, P < 0.001; AUC for 3- and 5- year OS, nomogram versus TNM staging system: training set, 0.748 and 0.741 versus 0.610 and 0.601; validation set, 0.715 and 0.753 versus 0.586 and 0.579, respectively).

CONCLUSIONS

Underweight patients had worse OS than non-underweight patients for all stages of CRC. Our nomogram can guide prognostic predictions and the treatment plan for underweight patients with CRC.

Clinical outcomes of surgical management for recurrent rectal prolapse: a multicenter retrospective study

Purpose

Methods

Results

Conclusion

Treatment outcomes of patients with involved resection margin after rectal cancer surgery: A nationwide population-based cohort study in South Korea

BACKGROUND

The involvement of resection margins after rectal cancer surgery by malignant tumors is a negative prognostic factor. Therefore, it is important to analyze treatment outcomes and establish adjuvant therapy.

METHODS

The Health Insurance Review and Assessment Service collects data from medical institutions in South Korea. We reviewed the database of this prospectively collected cohort for patients who underwent curative resection for rectal cancer.

RESULTS

Of the 5,620 patients, 113 (2.0%) were diagnosed with resection margin involvement after surgery. The resection margins of patients with mid-rectal cancer, pathologic stage III, mucinous/signet ring cell carcinoma, and undergoing emergency surgery were more frequently involved. Neoadjuvant chemoradiotherapy was a significant preventive factor for resection margin involvement (odds ratio = 0.53; 95% confidence interval [CI], 0.32-0.87; p = 0.012). The OS of patients with adjuvant treatment was better than that of patients without adjuvant treatment (5-year overall survival [OS]: 62.8% vs. 46.3%, p = 0.02). The administration of chemoradiotherapy was also significantly associated with better OS (hazard ratio = 0.36; 95% CI, 0.17-0.77; p = 0.009).

CONCLUSION

Efforts to acquire wider resection margins are necessary for patients with mid-rectal cancer, pathologic stage III, mucinous/signet ring cell carcinoma, and emergency surgery. Neoadjuvant chemoradiotherapy was a significant preventive factor for involved resection margin. Patients with resection margin involvement showed better OS after adjuvant treatment than those without adjuvant treatment. The adjuvant chemoradiotherapy was helpful to prevent the worse prognosis of these patients.

Clinical characteristics of rectal cancer patients with neoadjuvant chemoradiotherapy: a nationwide population-based cohort study in South Korea

Purpose

Neoadjuvant chemoradiotherapy has been accepted as a standard treatment for stage II–III rectal cancer. This study aimed to evaluate the clinical characteristics of patients who underwent neoadjuvant chemoradiotherapy for rectal cancer and effects on overall survival (OS) of neoadjuvant chemoradiotherapy in South Korea.

Methods

Patients who underwent curative resection for rectal cancer from 2014 to 2016 were retrospectively reviewed from the database of the National Quality Assessment program in South Korea. Patients were categorized into the upfront surgery group and neoadjuvant chemoradiotherapy group. We evaluated factors associated with the administration of neoadjuvant chemoradiotherapy and its effects on OS. Inverse probability of treatment weighting was performed to account for baseline differences between subgroups.

Results

A total of 6,141 patients were categorized into the upfront surgery group (n = 4,237) and neoadjuvant chemoradiotherapy group (n = 1,904). The neoadjuvant chemoradiotherapy was more frequently administered to male, midrectal cancer, and younger patients. In the neoadjuvant chemoradiotherapy group, old age, underweight, and pathologic stage were significant risk factors of OS, and male sex, the level of tumor and clinical stages were not associated with OS. After adjustment, the OS of the neoadjuvant chemoradiotherapy group followed the OS of the upfront surgery group of the same pathologic stage.

Conclusion

Male sex and the level of tumor were not related to the OS of rectal cancer patients with neoadjuvant chemoradiotherapy. The OS of patients who underwent neoadjuvant chemoradiotherapy was decided by their pathologic stages regardless of clinical stages.

Impact of D3 lymph node dissection on upstaging and short-term survival in clinical stage I right-sided colon cancer

BACKGROUND

D3 lymph node dissection is becoming the standard procedure for the treatment of advanced right colon cancer and has shown increasing evidence of its oncologic benefit. However, a clear indication for its application is lacking and data on this topic is unsatisfactory. Thus, the necessity for D3 lymph node dissection in clinical stage I right colon cancer remains controversial.

METHODS

We retrospectively analyzed data from clinical stage I right colon cancer patients who underwent radical surgery at three hospitals of Korea university medical center between January 2015 and June 2018. We compared surgical complications and short-term oncologic outcomes between D2 and D3 lymph node dissections in these patients.

RESULTS

Among 512 patients, 122 (23.8%) were clinical stage I. Of these, 88 and 34 patients received D2 and D3 lymph node dissection, respectively. There were no statistically significant differences in clinicopathologic variables and surgical outcomes between the two groups. Upstaging occurred in 16 patients (47.1%) in the D3 group and 23 patients (26.1%) in the D2 group. There were four recurrences in the D2 group but no recurrence in the D3 group. Log-rank tests showed no statistically significant difference in disease-free survival rates between the two groups (p = 0.210).

CONCLUSION

There was no significant difference in disease-free survival rates between D2 and D3 lymph node dissection in clinical stage I right colon cancer patients. However, recurrence occurred in the D2 group. Efforts to improve the accuracy of clinical staging are required and more studies with better quality are needed.

Effects of the proximity of metastasis to the central vessels of the liver on surgical outcomes and survival in colorectal cancer with liver metastasis

BACKGROUND

Resectability of liver metastasis is important to establish a treatment strategy for patients with colorectal cancer. We aimed to evaluate the effect of the distance from metastasis to the centre of the liver on surgical outcomes and survival after hepatectomy.

METHODS

The clinical data of a total of 155 patients who underwent hepatectomy for colorectal cancer with liver metastasis were retrospectively reviewed. We measured the minimal length from metastasis to the bifurcation of the portal vein at the primary branch of the Glissonean tree and defined it as 'centrality'. The postoperative outcomes and survival among the patients were then analysed.

RESULTS

Anatomic resections were more frequently performed, and the operative time was longer in the patients with high centrality (≤1.5 cm) than in the patients with low centrality (>1.5 cm). A size of ≥5 cm for the largest lesion, a number of lesions of ≥3 and centrality of ≤1.5 cm were found to be the independent risk factors of a positive resection margin after hepatectomy. The patients with high centrality showed worse recurrence-free survival than those with low centrality; however, there was no significant difference found in the overall survival. In the multivariate analysis, high centrality was not found to be associated with worse recurrence-free and overall survival.

CONCLUSION

Centrality significantly affected the surgical outcomes and treatment strategy for liver metastasis but did not influence the survival of the patients with colorectal cancer. Active efforts through surgical resections are important to treat liver metastasis of high centrality.

A multicentre comparative study between laparoscopic and open surgery for intussusception in adults

AIM

Intussusception in adults is rare and requires surgery in most cases. While abdominal laparoscopic surgery (LS) is becoming more popular, there are few reports on the outcomes of adult intussusception treated with LS. This study compared the feasibility of LS vs open surgery (OS) for adult intussusception.

METHOD

We reviewed retrospectively the medical records of adult patients with intussusception from three tertiary hospitals between 2000 and 2016. The patients were divided into LS and OS groups, and their surgical outcomes were compared.

RESULTS

Surgery was indicated in 71 patients with intussusception (41 LS and 30 OS). The median age of the patients was 49.0 and 51.5 years in the LS and OS groups, respectively (P = 0.930). Overall, nine (12.7%) patients had a negative laparotomy or laparoscopy with spontaneous reduction of the intussusception. Conversion to OS from LS was necessary in one patient (2.4%). The operative time and intra-operative and postoperative complication rates were not significantly different. However, there were more serious complications such as bowel perforation and major vessel injury in the LS group. The patients in the LS group had a shorter time to first food intake and hospital stay vs patients in the OS group (4.0 vs 6.0 days, P < 0.001, and 7.0 vs 10.5 days, P < 0.001, respectively).

CONCLUSION

LS may be feasible for adult intussusception; there may be more severe intra-operative complications than in OS.

A Review of Bowel Preparation Before Colorectal Surgery

Infectious complications are the biggest problem during bowel surgery, and one of the approaches to minimize them is the bowel cleaning method. It was expected that bowel cleaning could facilitate bowel manipulation as well as prevent infectious complications and further reduce anastomotic leakage. In the past, with the development of antibiotics, bowel cleaning and oral antibiotics (OA) were used together. However, with the success of emergency surgery and Enhanced Recovery After Surgery, bowel cleaning was not routinely performed. Consequently, bowel cleaning using OA was gradually no longer used. Recently, there have been reports that only bowel cleaning is not helpful in reducing infectious complications such as surgical site infection (SSI) compared to OA and bowel cleaning. Accordingly, in order to reduce SSI, guidelines are changing the trend of only intestinal cleaning. However, a consistent regimen has not yet been established, and there is still controversy depending on the location of the lesion and the surgical method. Moreover, complications such as Clostridium difficile infection have not been clearly analyzed. In the present review, we considered the overall bowel preparation trends and identified the areas that require further research.

Anti-metastatic effect of metformin via repression of interleukin 6-induced epithelial-mesenchymal transition in human colon cancer cells

Metformin, a first-line drug used to treat type 2 diabetes, has also been shown to have anticancer effects against a variety of malignancies, including colorectal cancer. Although inhibition of the mTOR pathway is known to be the most important mechanism for the antitumor effects of metformin, other mechanisms remain unclear. The purpose of this study was to identify the antitumor mechanism of metformin in colorectal cancer using high-throughput data, and then test the mechanism experimentally. We identified the gene signature of metformin-treated colon cancer cells. This signature was processed for prediction using colon adenocarcinoma patient data from the Cancer Genome Atlas to classify the patients showing a gene expression pattern similar to that in metformin-treated cells. This patient group showed better overall and disease-free survival. Furthermore, pathway analysis revealed that the metformin-predicted group was characterized by decreased interleukin (IL)-6 pathway signaling, epithelial–mesenchymal transition, and colon cancer metastatic signaling. We induced epithelial–mesenchymal transition in colon cancer cell lines via IL-6 treatment, which increased cell motility and promoted invasion. However, these effects were blocked by metformin. These findings suggest that blockade of IL-6-induced epithelial–mesenchymal transition is an antitumor mechanism of metformin.

The significance of microsatellite instability in colorectal cancer after controlling for clinicopathological factors

The colorectal cancer (CRC) patients with microsatellite instability (MSI) have distinct clinicopathological characteristics consisting of factors predicting positive and negative outcomes, such as a high lymph node harvest and poor differentiation. In this study, we measured the value of MSI as a prognostic factor after controlling for these discrepant factors. A total of 603 patients who underwent curative surgery for stages I to III colorectal cancer were enrolled. The patients were divided into microsatellite instability high (MSI-H) and microsatellite stable/microsatellite instability low (MSS/MSI-L) groups. Propensity score matching was used to match clinicopathological factors between the 2 groups. MSI-H patients had a high lymph node harvest (median: 31.0 vs 23.0, P < .001), earlier-stage tumors (P < .001), advanced T stage (89.3% vs 74.0%, P = .018), and poor differentiation (19.6% vs 2.0%, P < .001). Survival analysis showed better survival in the MSI-H group, but the difference was not statistically significant (P = .126). Propensity score matching was performed for significant prognostic factors identified by Cox hazard regression. After the matching, the survival difference by MSI status was estimated to be larger than before, and reached statistical significance (P = .045). In conclusion, after controlling for pathological characteristics, MSI-H could be a potent prognostic factor regarding patient survival.

Transglutaminase 2 Regulates Self-renewal and Stem Cell Marker of Human Colorectal Cancer Stem Cells

BACKGROUND/AIM

The aim of this study was to investigate the role of transglutaminase 2 (TGM2) in colorectal cancer stem cells (CCSCs).

MATERIALS AND METHODS

We used the TU12 cell line possessing CD133-expressing CCSCs. After isolating CD133 (-) and CD133 (+) CCSCs, we overexpressed and knocked-down TGM2 to investigate its role in human CCSCs.

RESULTS

The expression level of TGM2 was 25-fold higher in tumorigenic cells than non-tumorigenic cells. We found that knockdown of TGM2 by specific RNA interference markedly inhibited cell growth and caused down-regulation of the stemness markers, CD133, SOX2, and β-catenin. We further demonstrated that knockdown of TGM2 inhibited cell metastatic abilities by down-regulating N-cadherin and vimentin and up-regulating E-cadherin. These findings revealed that TGM2 expression is markedly increased in human colorectal cancer and that down-regulation of TGM2 in tumors may serve as a treatment for colorectal cancer patients. Therefore, this study indicate that TGM2 affects the metastatic potential and stemness of CCSCs by regulating EMT- and stemness-related proteins.

CONCLUSION

The metastatic potential of CSCs arises from highly expressed TGM2.

Efficacy and safety of a novel partially absorbable mesh in totally extraperitoneal hernia repair

Purpose

Partially absorbable mesh has been introduced and used for inguinal hernia repair for the purpose of minimizing pain and improving abdominal wall compliance. In this study, we evaluate the efficacy and safety of ProFlex mesh, a partially absorbed mesh with new structural architecture.

Methods

We retrospectively reviewed 64 cases of totally extraperitoneal herniorrhapy (TEP) from January 2013 to December 2014 for their clinical features, including operation time, pain, postoperative complications, and recurrence.

Results

There were no significant differences in operation time, hospital stay, postoperative pain, or complications between the 28 patients who received the ProFlex mesh and the 36 who received nonabsorbable lightweight mesh, although one patient who received the nonabsorbable had a recurrence during follow-up. There were differences in operation time, complications, and hospital stay according to the surgeon's previous operation volume.

Conclusion

This study showed that there were significant differences in the fixation strength of different polypropylene meshes in combination with various fibrin glues. ProFlex, a partially absorbable mesh with new architecture, was feasible and safe in TEP.

Reactive oxygen species modulator-1 (Romo1) predicts unfavorable prognosis in colorectal cancer patients

Background

Reactive oxygen species modulator-1 (Romo1) is a novel protein that has been reported to be crucial for cancer cell proliferation and invasion. However, its clinical implications in colorectal cancer patients are not well-known. For the first time, we investigated the association between Romo1 and the clinical outcomes of colorectal cancer patients.

Study

We examined Romo1 expression in resected tumor tissues immunohistochemically and assessed it with histological scores. We conducted survival analyses for patients who had curative resection (n = 190) in accordance with clinical parameters including level of Romo1 expression, and we examined the association between Romo1 expression and cell invasion using Matrigel invasion assay in colorectal cancer cells.

Results

We observed significantly longer mean disease-free survival in the low Romo1 group compared with the high Romo1 group (161 vs 127.6 months, p = 0.035), and the median overall survival of the low Romo1 group was significantly longer than that of the high Romo1 group (196.9 vs 171.3 months, p = 0.036). Cell invasiveness decreased in the Romo1 knockdown colorectal cancer cells in contrast to the controlled cells. Romo1 overexpression in tumor tissue was associated with a high lymph node ratio between the metastatic and examined lymph nodes (p = 0.025).

Conclusions

Romo1 overexpression in tumor tissue was significantly associated with survival in curatively resected colorectal cancer patients, suggesting Romo1 expression as a potential adverse prognostic marker. Increased Romo1 expression was found to be associated with high lymph node ratio. Cancer invasiveness appeared to be a key reason for the poor survival related to highly expressed Romo1.

Lymph Node Micrometastasis Cannot be Considered as Positive Lymph Node in Nonmetastatic Colorectal Cancer

The prognostic value of micrometastasis in colorectal cancer (CRC) remains controversial. The study investigated whether lymph node (LN) micrometastasis can have prognostic value in CRC as compared with macrometastasis. The study included 488 patients with curatively resected stage I, II, or III CRC treated between 2004 and 2011. Immuohistochemical staining with monoclonal antibody CAM 5.2 was performed on negative LNs by hematoxylin-eosin staining. The prognostic value of LN micrometastasis was investigated in multivariate analysis. Regression analysis was performed to identify a causal relationship between micro- and macrometastasis. Survival differences were compared between conventional N staging and hypothetic N staging taking micrometastasis in the positive node. A total of 93 patients (19.1%) showed LN micrometastasis. Patients with micrometastasis had more advanced tumor characteristics in terms of tumor size, grade, T stage, N stage, lymphatic invasion, and vascular invasion. In multivariate analysis, micrometastasis was not related with recurrence. Preoperative carcinoembryonic antigen level, neural invasion, and macrometastasis were independent risk factors in the analysis. Regression analysis showed that there was not a causal relationship between micro- and macrometastasis (R2= 0.004, P = 0.153). When the cumulative numbers of micro- and macrometastatic LNs were calculated together, the discriminative power of survival difference between each node stage became less prominent, compared with conventional N staging. LN micrometastasis is related with advanced tumor characteristics, but does not reflect poor prognosis in nonmetastatic CRC. Micrometastasis cannot be considered as positive LN to predict poor prognosis.

Lymph Node Micrometastasis Cannot Be Considered as Positive Lymph Node in Nonmetastatic Colorectal Cancer

The prognostic value of micrometastasis in colorectal cancer (CRC) remains controversial. The study investigated whether lymph node (LN) micrometastasis can have prognostic value in CRC as compared with macrometastasis. The study included 488 patients with curatively resected stage I, II, or III CRC treated between 2004 and 2011. Immuohistochemical staining with monoclonal antibody CAM 5.2 was performed on negative LNs by hematoxylin-eosin staining. The prognostic value of LN micrometastasis was investigated in multivariate analysis. Regression analysis was performed to identify a causal relationship between micro- and macrometastasis. Survival differences were compared between conventional N staging and hypothetic N staging taking micrometastasis in the positive node. A total of 93 patients (19.1%) showed LN micrometastasis. Patients with micrometastasis had more advanced tumor characteristics in terms of tumor size, grade, T stage, N stage, lymphatic invasion, and vascular invasion. In multivariate analysis, micrometastasis was not related with recurrence. Preoperative carcinoembryonic antigen level, neural invasion, and macrometastasis were independent risk factors in the analysis. Regression analysis showed that there was not a causal relationship between micro- and macrometastasis (R2 = 0.004, P = 0.153). When the cumulative numbers of micro- and macrometastatic LNs were calculated together, the discriminative power of survival difference between each node stage became less prominent, compared with conventional N staging. LN micrometastasis is related with advanced tumor characteristics, but does not reflect poor prognosis in nonmetastatic CRC. Micrometastasis cannot be considered as positive LN to predict poor prognosis.

Usefulness of (18)F-FDG PET/CT to Detect Metastatic Mucinous Adenocarcinoma Within an Inguinal Hernia

Metastatic mucinous adenocarcinoma in an inguinal hernia is a rare disease and the image findings of (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET)/computed tomography (CT) are little known. Here, we introduce a 57-year-old man with metastatic mucinous adenocarcinoma in an inguinal hernia. On initial (18)F-FDG PET/CT, hypermetabolism was observed in mucinous adenocarcinoma of the cecum, and adenocarcinomas of the transverse and ascending colon, respectively. Follow-up (18)F-FDG PET/CT revealed newly developed multiple hypermetabolism in peritoneal seeding masses and nodules in the pelvic cavity and scrotum. Peritoneal carcinomatosis in the right pelvic side wall was extended to the incarcerated peritoneum and mesentery in the right inguinoscrotal hernia.(18)F-FDG PET/CT was useful to reveal unexpected peritoneal seeding within the inguinal hernia. Also, this case demonstrated that metastatic mucinous adenocarcinomas had variably intense FDG uptake.

BMP-2 induces motility and invasiveness by promoting colon cancer stemness through STAT3 activation

Bone morphogenetic proteins (BMPs) have been involved in metastatic progression and tumorigenesis of many cancer types. However, it remains unclear how BMP-2 contributes to the initiation and development of these cancers. Here, we investigated the role of BMP-2 in colon cancer stem cell (CSC) development from colon cancer cells. We also determined the effects of BMP-2 on CSC development and epithelial-mesenchymal transition (EMT) in human colon cancer cell lines HCT-116 and SW620. We found that BMP-2 enhanced sphere formation of colon cancer cells without serum. Also, BMP-2-induced spheres displayed up-regulation of stemness markers (CD133+ and EpCAM+) and increased drug resistance, hallmarks of CSCs. Importantly, expression of EMT activators p-Smad1/5 and Snail and N-cadherin was increased in the spheres' cells, indicating that BMP-2 signaling might result in CSC self-renewal and EMT. Furthermore, siRNA-mediated knockdown of signal transducer and activator of transcription 3 (STAT3) in HCT-116 cells reversed BMP-2-induced EMT and stem cell formation. Taken together, our results suggest that the BMP-2 induced STAT3-mediated induction of colon cancer cell metastasis requires an EMT and/or changes in CSC markers.

The role of laparoscopic approach for anastomotic leakage after minimally invasive surgery for colorectal cancer

OBJECTIVES

The objectives of this study were to evaluate the feasibility and safety of a re-laparoscopic approach to manage anastomotic leakage after minimally invasive colorectal resection and to compare its clinical outcomes with those obtained using an open approach.

METHODS

We retrospectively reviewed clinical data from 1714 patients who underwent colorectal cancer resection from September 2006 to August 2009 at the Korea University Medical Center. Clinical data from a total of 57 surgery patients who developed anastomotic leakage were analyzed.

RESULTS

Twenty-six leakage cases were managed laparoscopically, whereas the remaining 31 leakage cases were managed using an open approach. There were no significant differences in age, sex, or other clinical features between patients in the two groups. The total operation time was shorter in the laparoscopic group (107.3 ± 68.1 minutes) than in the open group (126.5 ± 50.1 minutes), but this difference was not statistically significant (P = .230). Six cases in each group required additional procedures such as reoperation or percutaneous intervention (P = .126). There was one case of postoperative mortality in the open group. Median (quartiles 25%-75%) number of days required to resume a soft diet tended to be shorter in the laparoscopic group than the open group (5 [3-7] versus 6 [5-10] days; P = .057). Patients in both groups showed similar postoperative complications including intraabdominal abscess; however, the incidence of wound infection was significantly lower in the laparoscopic group than the open group (3.8% versus 25.8%; P = .031).

CONCLUSIONS

Compared with conventional open treatment of anastomotic leakage, the laparoscopic approach resulted in fewer wound complications and tendency of early recovery of bowel movement without an increase in adverse outcomes. Using a laparoscopic approach, all the advantages of minimally invasive surgery can be realized in patients who develop anastomotic leakage after minimally invasive surgery.

Optimal multidetector row CT parameters for evaluations of the breast: a phantom and specimen study

RATIONALE AND OBJECTIVES

The use of breast computed tomography (CT) has been limited by radiation hazard and image quality. The objective of this study was to compare radiation doses and image quality for different 64-channel multidetector row CT (MDCT) parameters, and to potentially provide optimal CT parameters for breast imaging.

MATERIALS AND METHODS

For assessment of radiation doses, CT dose index (CTDI(100)) values were obtained at various x-ray tube voltages (80, 120, 140 kVp) and currents (30, 50, 100, 150, 200 mAs) using a standard CT body dose phantom. To evaluate image quality, four fresh mastectomy specimens were scanned and three radiologists graded images for overall image quality, glandular tissue-fat conspicuity, and Cooper's ligament sharpness. Statistically, linear regression analyses and multiple comparisons were used for investigation of the relationship between radiation dose, image qualities, and CT parameters.

RESULTS

CTDI(100) values of < or =6 mGy were obtained at 80 kVp and any mAs, 120 kVp and 30 or 50 mAs, and 140 kVp and 30 or 50 mAs. Image quality at 80 kVp and 200 mAs, 120 kV and 50, 100, 150, or 200 mAs, and 140 kVp and all mAs values tested were significantly superior to those at 80 kVp and 30, 50, 100, or 150 mAs and 120 kV and 30 mAs (P < .05).

CONCLUSIONS

Based on our results, 80 kVp and 200 mAs, 120 kVp and 50 mAs, 140 kVp and 30 mAs, or 140 kVp and 50 mAs can be used for breast MDCT scanning to reduce radiation dose and preserve image quality and 140 kVp at 30 mAs is the optimal setting.

Acquired omental cystic lymphangioma after subtotal gastrectomy: a case report

We herein describe a case of cystic lymphangioma in the greater omentum of the remnant stomach, which is thought it to be related with subtotal gastrectomy 10 yr ago for early gastric cancer. A 76-yr-old man was admitted to our department with postprandial abdominal discomfort and bowel habit change. Intraabdominal multilocular cystic mass was detected by ultrasonography and computed tomography. We performed a complete En-bloc tumor resection including spleen and distal pancreas, and histological examination confirmed cystic lymphangioma originated from the greater omentum of the remnant stomach. Although the etiology of omental lymphangioma remains largely unclear, these findings suggested strongly that obstruction of the lymphatic vessels after gastric resection for gastric carcinoma might be the most plausible cause. The surgical extirpation with resection of organs involved appears to be a treatment of choice for such unusual case.

Exophytic inflammatory myofibroblastic tumor of the stomach in an adult woman: A rare cause of hemoperitoneum

Inflammatory myofibroblastic tumor (IMT) of the stomach in adults is extremely rare, with unpredictable prognosis. We present a 55-year-old woman with a gastric IMT. She experienced sudden abdominal pain 4 d previously. Physical examination showed mild abdominal tenderness in the hypogastrium, but no palpable abnormal abdominal mass. Abdominal CT showed a mass of approximately 8 cm in the gastrocolic ligament. On laparoscopic exploration, unexpected hemoperitoneum of approximately 1.5 L of blood was found, and an exophytic gastric mass of approximately 10 cm, appeared from the anterior wall of the gastric body along the greater curvature. Laparoscopy further showed that non-clotting blood in the abdominal cavity seemed to be from the gastric tumor. After conversion to open surgery for more precise evaluation of the cause of hemoperitoneum and the large friable tumor, gastric wedge resection, including the tumor, was conducted. The final diagnosis was consistent with IMT that originated from the gastric wall.

Mirizzi syndrome in an anomalous cystic duct: A case report

Mirizzi syndrome is a rare complication of gallstone disease, and results in partial obstruction of the common bile duct or a cholecystobiliary fistula. Moreover, congenital anatomical variants of the cystic duct are common, occurring in 18%-23% of cases, but Mirizzi syndrome underlying an anomalous cystic duct is an important clinical consideration. Here, we present an unusual case of typeIMirizzi syndrome with an uncommon anomalous cystic duct, namely, a low lateral insertion of the cystic duct with a common sheath of cystic duct and common bile duct.

Role of regular follow-up after curative surgery for colorectal cancer

BACKGROUND/AIMS

This investigation aimed to estimate the value of regular follow-up programs after curative resection for colorectal cancer.

METHODOLOGY

We compared the recurrence rate, rate of curative re-resection, and survival rate between groups who had either regular or irregular follow-up. The medical records of 397 consecutive patients, who underwent a curative resection for colorectal cancer between January 1994 and December 1997, were analyzed retrospectively.

RESULTS

The recurrence rate was 19.4% and 20.8% in the regular and irregular follow-up groups (P > 0.05), respectively. There was a significant difference in the asymptomatic recurrence rate (62.9 vs. 18.7%; P = 0.021), but curative re-resection was possible in 18 (29.0%) of those patients with cancer recurrence in the regular follow-up group, and in 2 (12.5%) in the irregular follow-up group, which was not significantly different (P > 0.05). 5-year survival rate between the groups was not significantly different (78.1 vs. 61.2%; P > 0.05).

CONCLUSIONS

A regular follow-up program after a curative resection for colorectal cancer, although facilitating detection of recurrence before symptoms developed, was unlikely to succeed in increasing the rate of a curative intent re-resection and survival remarkably.

Selective inhibition of polymorphonuclear neutrophils by resuscitative concentration of hypertonic saline

OBJECTIVES

This study investigated the effect of hypertonic saline on the role of polymorphonuclear neutrophils (PMNs) in the inflammatory response and the effect of hypertonic saline infused at different phases in relation to an inflammatory stimulus.

MATERIALS AND METHODS

PMNs were isolated from peripheral blood of healthy volunteers (Boyum's method) and cultured in three different media ([Na+] = 140 mmol/l, 180 mmol/l, and 200 mmol/l). PMNs were then stimulated with fMLP (N-formyl-methionyl-leucyl-phenylalanine) and H2O2 synthesis was quantified by flow cytometry at 5, 30, 60, 120, and 180 minutes. PMNs were treated with hypertonic saline before, simultaneously with, and after fMLP stimulation, and H2O2 synthesis quantified again.

RESULTS

H2O2 synthesis was two or three times higher in fMLP stimulated than in non-stimulated PMNs, and it reached maximum level at 120 minutes. In the absence of fMLP stimulation, there was no significant difference between control and hypertonic saline with regard to activity of H2O2 synthesis. In the presence of fMLP stimulation, H2O2 synthesis significantly decreased in PMNs treated with hypertonic saline. There was no significant difference between the two hypertonic saline solutions ([Na+] = 180 mmol/l and 200 mmol/l) with regard to H2O2 synthesis. However, H2O2 synthesis decreased in PMNs treated with hypertonic saline before and simultaneously with fMLP stimulation, but was not significantly decreased in the cells treated with hypertonic saline after fMLP stimulation.

CONCLUSIONS

Hypertonic saline appears to decrease H2O2 in stimulated neutrophils. This may be a further beneficial role of hypertonic saline when used clinically as an early resuscitation fluid.

The first case of primary retroperitoneal mucinous cystadenoma in Korea: a case report

Primary mucinous cystic cystadenomas of the retroperitoneum are very rarely encountered, and there have been only about 30 cases reported in the literature. The histogenesis of primary mucinous cystadenomas is unclear. Most authors suggested that it develops through mucinous metaplasia in a pre-existing mesothelium-lined cyst. Complete surgical excision is the only treatment and it is required for the final diagnosis and cure. We present here a case report of a 38-year-old Korean woman with primary retroperitoneal cystadenoma. It was a thin-walled, multilocular cyst with a dominant loculus that measured 10.0 x 7.5 x 5.5 cm3 in size, and to the best of our knowledge, this is the first such case to be reported in in Korea.

Transforming growth factor-beta1 expression and the role of angiotensin-converting enzyme inhibitor on perianastomotic intimal hyperplasia in polytetrafluoroethylene graft implanted in rabbit carotid artery

The purpose of this study was to evaluate the relationship between intimal hyperplasia and transforming growth factor-beta1 (TGF-beta1) mRNA expression in synthetic arterial grafts and also to clarify the effect of angiotensin-converting enzyme inhibitor (ACEI) on perianastomotic intimal hyperplasia and TGF-beta1 mRNA expression. Thirty New Zealand White rabbits were randomly divided into two groups (15 each); one group was administered Captopril 10 mg/kg/day per os as an ACE inhibitor, and the other group received on saline as a vehicle from 7 days prior to operation until the graft was harvest (1, 8, or 14 weeks). A 10-mm segment of an expanded polytetrafluoroethylene graft (3 mm in diameter) was implanted in the right common carotid artery of the rabbits; 15 rabbits had by-pass grafting alone (Graft Alone group) and the other 15 rabbits had by-pass graft along with the ACEI (Graft plus ACEI group). The artery grafts were harvested. The intima to media height ratio (IMHR) and the TGF-beta1 mRNA expression level in perianastomotic graft tissue by reverse transcription-polymerase chain reaction (RT-PCR). The IMHRs gradually increased from 1 to 14 weeks in both groups (vs. 1 wk in each group, p<0.05). The IMHRs of the Graft plus ACEI group were comparable to those of Graft Alone group at 1 week, but significantly lower at 8 and 14 weeks (vs. Graft Alone group, p<0.05). The TGF-beta1 mRNA expression levels of the Graft plus ACEI group were clearly lower than those of the Graft Alone group at 1 and 8 weeks (vs. Graft Alone group, p<0.05), but similar at 14 weeks. TGF-beta1 in the synthetic artery graft of the Graft Alone group was up-regulated as early as 1 week after the operation, when no definitive development of a quantifiable neointima was observed. The TGF-beta1 mRNA expression of the Graft Alone group was highest at 8 weeks and lowest at 14 weeks (vs. 1 week, *p<0.05), but such time-dependent changes were not observed in the Graft plus ACEI group. The results indicated that ACEI reduced intimal hyperplasia in the grafts of the Graft plus ACEI group and also suppressed TGF-beta1 mRNA expression in perianastomotic intimal hyperplasia tissues to the normal artery level. Perianastomotic intimal hyperplasia in synthetic arterial graft is considered to be related to TGF-beta1, the expression of which is locally mediated by angiotensin II and, therefore, suppressed by ACEI.

Subcapital fractures associated with extensive osteonecrosis of the femoral head

The authors reviewed 10 patients with subcapital fractures associated with extensive osteonecrosis of the femoral head and distinguished these fractures from traumatic femoral neck fractures The mean age of the patients was 52 years (range, 36-68 years). Nine patients were younger than 60 years. Eight patients had risk factors for osteonecrosis. Necrosis was extensive and involved nearly the whole femoral head. Fracture occurred at the junction between a necrotic bone and reparative bone and extended downward through the reparative interface to the healthy inferior cortex of the femoral neck. Patients experienced hip pain that was aggravated gradually during a period of 1 to 24 weeks before diagnosis of the fracture. In all patients, the opposite femoral head was involved with osteonecrosis. In two femoral heads, slight collapse or subchondral fracture (crescent sign) also was observed. No patient had a history of precipitating trauma. In patients younger than 60 years with a subcapital fracture, fracture associated with extensive osteonecrosis of the femoral head should be suspected when a history of trauma is not obvious, when the opposite hip shows findings of osteonecrosis, and when the patient has a risk factor of osteonecrosis. In these fractures, osteosynthesis rarely should be considered because of the high failure rate caused by additional progression of extensive osteonecrosis and the probability of nonunion.

Preoperative and postoperative evaluation of intra-articular fractures of the calcaneus based on computed tomography scanning

OBJECTIVE

To define the relationship between postoperative congruency of the posterior facet of the subtalar joint based on computed tomography (CT) and clinical results.

DESIGN

Preoperative and postoperative CT scans were taken prospectively and analyzed.

SETTING

University medical center.

PATIENTS

Twenty-nine displaced fractures in twenty-five patients.

INTERVENTION

All patients were treated with open reduction and internal fixation without bone graft.

MAIN OUTCOME MEASURES

Postoperative CT findings were classified into three groups, according to the degree of displacement: anatomic, no displacement; nearly anatomic, displaced less than two millimeters; and approximate, displaced more than two millimeters.

RESULTS

The reduction state after operative treatment for the cases with more comminution showed worse results when analyzed in both preoperative and postoperative CT scans. Fifteen of seventeen fractures (88 percent) with anatomic reduction and seven of eight fractures (87 percent) with nearly anatomic reduction had excellent or good clinical results. In contrast, no fracture with an approximate reduction had an excellent result.

CONCLUSION

An excellent or good clinical result can be expected when the postoperative displacement of the posterior facet of the subtalar joint is less than two millimeters.