Laparoscopic colectomy for patients with poor American Society of Anesthesiology classifications.

INTRODUCTION: The American Society of Anesthesiologists (ASA) classification is used to assess the fitness of a patient for surgery. Whether laparoscopic surgery is appropriate for colorectal cancer patients with poor ASA performance status (PS) remains unclear. METHODS: Among 4585 patients who underwent colorectal surgery between 2016 and 2023, this study retrospectively reviewed all 458 patients with ASA-PS ≥3. Patients were divided into two groups: patients treated by open surgery (O group, n = 80); and patients treated by laparoscopic surgery (L group, n = 378). We investigated the impact of surgical approach on postoperative complications in patients with colorectal cancer and ASA-PS ≥3. RESULTS: Operation time was longer (170 min vs. 233 min, p < .001), blood loss was less (156 mL vs. 23 mL, p < .001), postoperative complications were less frequent (40.0% vs. 25.1%, p = .008), and hospital stay was shorter (23 days vs. 14 days, p < .001) in L group. Univariate analysis revealed rectal cancer, open surgery, longer operation time, and blood loss as factors significantly associated with postoperative complications. Multivariate analysis revealed open surgery (odds ratio [OR] 2.100, 95% confidence interval [CI] 1.164-3.788; p = .013) and longer operation time (OR 1.747, 95% CI 1.098-2.778; p = .018) as independent predictors of postoperative complications. CONCLUSION: Laparoscopic surgery provides favorable outcomes for colorectal cancer patients with poor ASA-PS.

The C-reactive protein-albumin-lymphocyte (CALLY) index is a useful predictor of postoperative complications in patients with a colonic stent for obstructive colorectal cancer: a Japanese multicenter study.

PURPOSE: The C-reactive protein-albumin-lymphocyte (CALLY) index is a novel score that offers a good reflection of nutritional status, inflammatory response, and immune system status. The CALLY index is reported to correlate with the prognosis of various carcinomas. The purpose of the present study was to investigate the association between the CALLY index and the short-term prognosis of obstructive colorectal cancer managed with a colonic stent. METHODS: The subjects of this retrospective study were 263 patients who underwent colorectal resection after colonic stenting for obstructive colorectal cancer between 2016 and 2023. Patients were classified into a group with a low CALLY index (CALLY-L group, n = 85) and a group with a high (CALLY-H group, n = 178) CALLY index. RESULTS: The CALLY-L group had greater blood loss (53 mL vs 20 mL, p = 0.002) and higher poor performance status (PS3; 20% vs 10.1%, p = 0.033), open surgery (21.2% vs 7.3%, p = 0.001), distant metastases (41.2% vs 20.8%, p = 0.01), and postoperative complications (30.6% vs. 18.5%, p = 0.039) than the CALLY-H group. Multivariate analysis identified a prolonged operative time (odds ratio 1.983, 95% confidence interval 1.013-3.881; p = 0.045), greater blood loss (odds ratio 2.572, 95% confidence interval 1.291-5.129; p = 0.007) and a low CALLY index (odds ratio 1.961, 95% confidence interval 1.013-3.795; p = 0.045) as independent predictors of complications. CONCLUSION: The CALLY index may be a useful predictor of postoperative complications of obstructive colorectal cancer.

Effect of the lymphocyte-to-monocyte ratio on the prognosis of patients with obstructive colorectal cancer with a colonic stent: a retrospective multicenter study in Japan.

PURPOSE: The prognostic value of the lymphocyte-to-monocyte (LMR) ratio has been reported for various cancers, including colorectal cancer (CRC). The insertion of colonic stents is considered effective for patients with surgically indicated obstructive CRC, but their LMR can vary depending on factors such as inflammation associated with stent dilation and improvement of obstructive colitis. However, the usefulness of the LMR in patients with obstructive CRC and colonic stents and the optimal timing for its measurement remain unclear. We conducted this study to investigate the relationship between the pre-stent LMR and the mid-term prognosis of patients with obstructive CRC and stents as a bridge to surgery (BTS). METHODS: The subjects of this retrospective multicenter study were 175 patients with pathological stage 2 or 3 CRC. Patients were divided into a low pre-stent LMR group (n = 87) and a high pre-stent LMR group (n = 83). RESULTS: Only 3-year relapse-free survival differed significantly between the low and high pre-stent LMR groups (39.9% vs. 63.6%, respectively; p = 0.015). The pre-stent LMR represented a prognostic factor for relapse-free survival in multivariate analyses (hazard ratio 2.052, 95% confidence interval 1.242-3.389; p = 0.005), but not for overall survival. CONCLUSIONS: A low pre-stent LMR is a prognostic factor for postoperative recurrence in patients with obstructive CRC and a colonic stent as a BTS.

Risk factors for pulmonary complications after colorectal cancer surgery: a Japanese multicenter study.

PURPOSE: Pulmonary complications (PC) are a serious condition with a 20% mortality rate. However, few reports have examined risk factors for PC after colorectal surgery. This study investigated the frequency, characteristics, and risk factors for PC after colorectal cancer surgery. METHODS: Between January 2016 and December 2022, we retrospectively reviewed 3979 consecutive patients who underwent colorectal cancer surgery in seven participating hospitals. Patients were divided into patients who experienced PC (PC group, n = 54) and patients who did not (non-PC group, n = 3925). Clinical and pathological features were compared between groups. RESULTS: Fifty-four patients (1.5%) developed PC, of whom 2 patients (3.7%) died due to PC. Age was greater (80 years vs 71 years; p < 0.001), frequency of chronic obstructive pulmonary distress was greater (9.3% vs 3.2%; p = 0.029), performance status was poorer (p < 0.001), the proportion of underweight was higher (42.6% vs 13.4%, p < 0.001), frequency of open surgery was greater (24.1% vs 9.3%; p < 0.001), and blood loss was greater (40 mL vs 22 mL; p < 0.001) in the PC group. Multivariate analysis revealed male sex (odds ratio (OR) 2.165, 95% confidence interval (CI) 1.176-3.986; p = 0.013), greater age (OR 3.180, 95%CI 1.798-5.624; p < 0.001), underweight (OR 3.961, 95%CI 2.210-7.100; p < 0.001), and poorer ASA-PS (OR 3.828, 95%CI 2.144-6.834; p < 0.001) as independent predictors of PC. CONCLUSION: Our study revealed male sex, greater age, underweight, and poorer ASA-PS as factors associated with development of PC, and suggested that pre- and postoperative rehabilitation and pneumonia control measures should be implemented for patients at high risk of PC.

Short- and Long-term Outcomes After Colonic Stent Insertion as a Bridge to Surgery in Elderly Colorectal Cancer Patients.

BACKGROUND/AIM: Colonic stents have been inserted as a bridge to surgery in patients with resectable colorectal cancer, allowing bowel decompression for systemic assessment and better preparation to avoid stoma construction. However, reports of short- and long-term prognoses for elderly patients remain limited. PATIENTS AND METHODS: This retrospective study reviewed 175 consecutive patients who underwent colonic stent insertion for bowel obstruction followed by curative colectomy. Patients were divided into those >80 years old (Old, n=49) and those <80 years old (Young, n=126). After propensity score matching, 41 patients in each group matched. RESULTS: Before matching, performance status was poorer (p<0.001), postoperative complication rate was higher (p=0.009), adjuvant chemotherapy rate was lower (p<0.001), and hospital stay was longer (p<0.001) in the Old group. After matching, adjuvant chemotherapy rate was lower (9.8% vs. 39.0%; p=0.003) and hospital stay was longer (14 vs. 12 days; p=0.029) in the Old group. Five-year relapse-free survival (42.9% vs. 68.8%; p=0.200), overall survival (66.3% vs. 87.7%; p=0.081), and cancer-specific survival (68.2% vs. 87.7%; p=0.129) rates were comparable between groups. CONCLUSION: Colorectal resection after colonic stent insertion is useful for elderly patients, with potential to reduce postoperative complication rates and achieve good long-term results with appropriate case selection.

Impact of institutional volume on short- and long-term outcomes after laparoscopic colectomy.

INTRODUCTION: The impact of institutional volume on postoperative outcomes after laparoscopic colectomy is still being debated. This study aimed to investigate whether differences in postoperative outcomes of laparoscopic colon resection exist between high- and low-volume centers. METHODS: Data were reviewed for 1360 patients who underwent laparoscopic colectomy for colon cancer between 2016 and 2022. Patients were divided according to whether they were treated at a high-volume center (≥100 colorectal surgeries annually; n = 947) or a low-volume center (<100 colorectal surgeries annually; n = 413). Propensity score matching was applied to balance covariates and minimize selection biases that could affect outcomes. Finally, 406 patients from each group were matched. RESULTS: After matching, patients from high-volume centers showed a higher number of retrieved lymph nodes (19 vs. 17, p < .001) and more frequent involvement of expert surgeons (98.3% vs. 88.4%, p < .001). Postoperative complication rates were similar between groups (p = .488). No significant differences between high- and low-volume centers were seen in relapse-free survival (88.8% each, p = .716) or overall survival (85.7% vs. 82.8%, p = .480). CONCLUSION: The present study suggests that in appropriately educated organizations, relatively safe procedures and good prognosis may be obtained for laparoscopic colectomy cases, regardless of institutional volume.

Intestinal Behçet's and suspected intestinal Behçet's disease: a report of four surgical cases.

BACKGROUND: Intestinal Behçet's disease (BD) is often associated with ulceration that requires surgery, including perforation and abscess formation. However, no consensus has been reached on the optimal extent of resection or treatment strategy. This study reviewed four cases of intestinal or suspected intestinal BD. CASE PRESENTATIONS: In Case 1, a 74-year-old woman diagnosed with BD 2 years earlier was treated with anti-tumor necrosis factor α antibody (Infliximab) and steroids. She had oral and pubic ulcers. After close investigation of abdominal pain, perforation of the gastrointestinal tract was suspected and surgery was performed. Multiple perforating ulcers and abscesses were found in the distal ileum, and the small intestine was resected. Postoperatively, the patient was treated with an increased steroid dose and symptoms have remained stable. Case 2 involved a 69-year-old woman with oral and pubic ulcers, ocular ulcer, and skin lesions. She experienced sudden onset of abdominal pain during treatment for lymphoma. She showed multiple perforating ulcers throughout the ileum and underwent resection of the small intestine and ileostomy. Upper abdominal pain appeared during postoperative treatment for high-output syndrome. The patient underwent omentoplasty after perforation of the upper gastrointestinal tract was diagnosed. Postoperatively, anti-interleukin-1 beta antibodies (canakinumab) was administered to control the disease. Case 3 involved an 81-year-old, previously healthy woman. She presented to her previous physician with complaints of pubic ulcer, hemorrhage and abdominal pain. Colonoscopy showed multiple ulcers throughout the entire colon. Steroid therapy was started, but bleeding proved difficult to control and total proctocolectomy was performed. Histopathology revealed multiple perforating ulcers and BD was diagnosed. Postoperatively, the patient remains under steroid control. Case 4 involved a 43-year-old man with abdominal pain who showed abscess formation in the ileocecal region. After excision of the ileocecal area, multiple ulcers were diagnosed. Two years later, abdominal pain recurred and free air was found in the abdomen on close imaging. Emergency anastomotic resection was performed due to ulceration and perforation of the anastomosis. CONCLUSIONS: Intestinal BD may flare up after surgical treatment and require multiple surgeries. Introducing pharmacotherapy as soon as possible after surgical treatment is important to control the disease.

Prognostic value of lymph node distribution after laparoscopic colectomy with Japanese D3 dissection.

PURPOSE: Positive pathologic lymph nodes in colorectal cancer represent an important prognostic indicator. Whether lymph node distribution or the number of metastatic nodes is more strongly associated with survival prediction remains controversial. METHODS: Among 3449 colorectal cancer surgeries performed at Nagasaki University Hospital and five affiliated institutions from April 2016 to March 2022, we investigated 604 patients who underwent laparoscopic radical resection and were diagnosed with pathological stage III cancer. Patients were divided into two groups according to whether they had central vessel metastasis (LND3 group, n=42) or not (LND1/2 group, n=562). After adjusting for background factors using propensity score matching, the LND3 group included 42 patients and the LND1/2 group included 40 patients. Patient background characteristics and prognosis were compared between these two groups. RESULTS: Before matching, frequencies of right-side colon cancer (64.3% vs 38.1%, p=0.001), multivisceral resection (11.9% vs 4.4%, p=0.039), clinical N2 status (40.5% vs 22.6%, p=0.032), and pathological N2 (73.8% vs 22.6%, p<0.001) were all greater, and the number of lymph nodes retrieved was higher (24 vs 19, p=0.042) in the LND3 group. After matching, no differences in any clinical factors were evident between groups. Five-year RFS (44.8% vs 77.1%, p=0.004) and OS (43.1% vs 83.2%, p<0.001) were worse in the LND3 group. Adjuvant chemotherapy improved RFS (adjuvant chemotherapy (+) vs adjuvant chemotherapy (-): 62.1% vs 27.7%, p=0.047) in the LND3 group. CONCLUSION: LND3-positive patients show poorer prognosis than LND1/2 patients and should be treated with an appropriate perioperative treatment strategy.

A case of pancreaticoduodenal artery bleeding after laparoscopic right colectomy requiring open hemostasis.

BACKGROUND: Pancreatic and duodenal-related complications after right colectomy carry a higher risk of mortality. CASE PRESENTATION: A 64-year-old woman underwent laparoscopic right colectomy for a laterally spreading tumor in the cecum. On postoperative day 10, she experienced sudden hematemesis. Contrast-enhanced computed tomography (CT) of the abdomen showed a large amount of hemorrhage in the stomach, but no obvious extravasation. In addition, free air was observed near the duodenal bulb. Despite blood transfusion, vital signs remained unstable and emergency surgery was performed. The abdomen was opened through midline incisions in the upper and lower abdomen. A fragile wall and perforation were observed at the border of the left side of the duodenal bulb and pancreas, with active bleeding observed from inside. As visualization of the bleeding point proved difficult, the duodenum was divided circumferentially to confirm the bleeding point and hemostasis was performed using 4-0 PDS. The left posterior wall of the duodenum was missing, exposing the pancreatic head. For reconstruction, the jejunum was elevated via the posterior colonic route and the duodenal segment and elevated jejunum were anastomosed in an end-to-side manner. Subsequently, gastrojejunal and Brown anastomoses were added. Drains were placed before and after the duodenojejunal anastomosis. Postoperative vital signs were stable and the patient was extubated on postoperative day 1. Follow-up contrast-enhanced CT of the abdomen showed no active bleeding, and the patient was discharged home on postoperative day 21. As of 6 months postoperatively, the course of recovery has been uneventful. CONCLUSIONS: We encountered a case of pancreaticoduodenal artery hemorrhage after laparoscopic right colectomy. Bleeding at this site can prove fatal, so treatment plans should be formulated according to the urgency of the situation.

Risk factors for reoperation within 30 days in laparoscopic colorectal cancer surgery: A Japanese multicenter study.

INTRODUCTION: Thirty-day reoperation rate reflects short-term surgical outcomes following surgery. Laparoscopic surgery for colorectal cancer reportedly has positive effects on postoperative complications. This retrospective study investigated risk factors for 30-day reoperation rate among patients after laparoscopic colorectal cancer surgery using a multicenter database. METHODS: Participants comprised 3037 patients who had undergone laparoscopic resection of colorectal cancer between April 2016 and December 2022 at the Nagasaki University and six affiliated centers, classified into those who had undergone reoperation within 30 days after surgery (RO group; n = 88) and those who had not (NRO group; n = 2949). Clinicopathological characteristics were compared between groups. RESULTS: In the RO group, anastomotic leakage occurred in 57 patients (64.8%), intestinal obstruction in 12 (13.6%), and intraabdominal abscess in 5 (5.7%). Female patients were more frequent, preoperative treatment less frequent, body mass index (BMI) lower, operation time longer, blood loss greater, and hospital stay longer in the RO group (p < .05 each). Multivariate analysis revealed BMI (odds ratio, 0.415; 95% confidence interval, 0.218-0.787; p = .021) and poor performance status (odds ratio, 1.966; 95% confidence interval, 1.106-3.492; p = .021) as independent predictors of reoperation. CONCLUSION: Perioperative measures are warranted for patients with low BMI and poor performance status undergoing laparoscopic colorectal surgery.

Long-term outcomes and early recurrence after resection for metachronous pulmonary metastases from colorectal cancer.

PURPOSE: Properly selecting patients for aggressive curative resection for pulmonary metastases (PMs) from colorectal cancer (CRC) is desirable. We purposed to clarify prognostic factors and risk factors for early recurrence after metachronous PM resection. METHODS: Clinical data of 151 patients who underwent R0 resection for metachronous PMs from CRC at two institutions between 2008 and 2021 were reviewed. RESULTS: Seventy-six patients (50.3%) were male, and the median age was 71 (42-91) years. The numbers of colon/rectal cancers were 76/75, with pStage I/II/III/IV/unknown in 15/34/86/13/3. The duration from primary surgery to PM was 19.7 (1.0-106.4) months. The follow-up period was 41.9 (0.3-156.2) months. The 1-, 3-, and 5-year recurrence-free survival (RFS) rates were 75.1%, 53.7%, and 51.1%, and the 1-, 3-, and 5-year overall survival (OS) rates were 97.7%, 87.5%, and 68.2%. On multivariate analysis, lymph node metastasis of the primary lesion (HR 1.683, 95%CI 1.003-2.824, p = 0.049) was an independent predictor of poor RFS, and history of resection for extrapulmonary metastasis (e-PM) (HR 2.328, 95%CI 1.139-4.761, p = 0.021) was an independent predictor of poor OS. Patients who experienced early recurrence (< 6 months) after PM resection showed poorer OS than others (3-year OS 50.8% vs. 90.2%, p = 0.002). On multivariate analysis, e-PM was an independent predictor of early recurrence after PM resection (OR 3.989, 95%CI 1.002-15.885, p = 0.049). CONCLUSION: Since a history of e-PM was a predictor of early recurrence and poor OS after R0 resection for PM, surgical treatment of patients with a history of e-PM should be considered carefully.

Development of Medical Shark Skin Forceps: Improved Grasping Power and Easy Manipulation.

Background and Objectives: Important safety requirements for forceps used in surgical procedures are the ability to stably grasp fine tissue and to cause minimal tissue damage. Shark skin has the structural feature of circumpolar scales, which increase the frictional force of the scales by roughening their surface. We have developed and patented medical forceps with a shark skin pattern placed on the tip surfaces. The aim of this study was to examine the safety and efficacy of the shark skin forceps compared with existing forceps, both fundamentally and clinically. Methods: To evaluate gripping power and usability, we compared bead transfer times for each forceps type. Grasping force and frictional force were measured quantitatively and compared among the types. To evaluate safety, we performed pathological examination of lung and urethral tissue after grasping, in an animal experiment. Subjective assessment of user experience was then performed using a questionnaire. Results: In the dry lab assessment, transfer time was fastest using the shark skin forceps (34 s vs 61 s and 62 s, p < 0.05). Frictional force values were highest for the shark skin forceps (p < 0.05). In the animal experiment, there was no difference in pathological tissue damage to lung or ureter tissues among the forceps types after grasping. The questionnaire responses indicated advantages of the shark skin forceps in terms of ease of grasping membranes and lower degree of grasp failure. Conclusion: Forceps with shark skin on the tips showed greater stability of tissue grasping and equivalent safety compared with existing forceps.

Malignant peripheral nerve sheath tumor in the pelvis: a case report.

BACKGROUND: Malignant peripheral nerve sheath tumors (MPNSTs) are malignancies that arise or differentiate from or infiltrate peripheral nerves and account for approximately 5% of soft-tissue malignancies. Approximately half of MPNSTs develop in patients with neurofibromatosis type 1 (NF1), a hereditary disease. MPNSTs occur mainly in the trunk, proximal extremities, and neck, but can on rare occasion arise in or near the gastrointestinal tract, and intestinal complications have been reported. We describe herein a case with resection of an MPNST arising in the pelvic region. CASE PRESENTATION: A 51-year-old woman had undergone repeated resections for systemic neurofibrosis associated with NF1. This time, a pelvic tumor was noted on follow-up positron emission tomography computed tomography (CT). She presented with slowly progressive radiating pain in the lower extremities and was referred to our hospital for tumor resection. Contrast-enhanced CT showed a 75 × 58-mm mass in the right greater sciatic foramen directly below a 24 × 28-mm mass. Open pelvic tumor resection was performed for pelvic neurofibroma. The obturator nerve was identified lateral to the main tumor and the sciatic nerve was identified dorsally, then dissection was performed. The closed nerve was spared, while the sciatic nerve was partially dissected and the two tumors were removed. Both tumors were elastic and hard. Pathologic findings were MPNST for the large specimen and neurofibroma with atypia for the small specimen. The patient developed temporary postoperative ileus, but is generally doing well and is currently free of recurrence or radiating pain. The patient is at high risk of recurrence and close monitoring should be continued. CONCLUSIONS: We encountered a rare case of MPNST. Due to the high risk of recurrence, surgery with adequate margins was performed, with a requirement for appropriate follow-up.

Efficacy of Neutrophil-to-Lymphocyte Ratio for Cancer-Specific Survival in Elderly Patients with Localized Colon Cancer: A Single Center Propensity Score-Matched Analysis.

Purpose: The prognostic value of neutrophil-to-lymphocyte ratio (NLR) has been studied for colorectal cancer. Elderly patients in general tend to have comorbidities and decreased organ function that potentially influence the NLR score. The aim of this study was to investigate the relationship between NLR and cancer-specific survival in elderly patients with colon cancer, using a propensity score-matched analysis. Patients and Methods: A total of 203 patients aged over 75 years who underwent curative resection for colon cancer and were diagnosed pathologically with stage II/III disease were eligible for entry to the study. Patients were divided into two groups according to NLR score: NLR-High (NLR≥4.5) group (NLR-H, n=60) and NLR-Low (NLR<4.5) group (NLR-L, n=143). After propensity score matching, 57 patients in each group were matched. Results: Before matching, Charlson comorbidity index was significantly higher in the NLR-H group (4 vs 2, p<0.001). After matching, all factors were similar between the groups. The median follow-up period was 43 months (range, 1-160 months). Five-year relapse-free-survival (69.8% vs 87.3%, p=0.030) and cancer-specific survival (83.0% vs 96.0%, p=0.042) were significantly lower in the NLR-H group. Conclusion: NLR appears to be a cancer-specific prognostic marker in elderly patients with colon cancer.

Gustave Roussy Immune Score for Predicting Postoperative Complications and Non-cancer Death in Elderly Patients With Colon Cancer.

BACKGROUND/AIM: The Gustave Roussy Immune (GRIm) score is aa prognostic marker in various cancer types. The aim of this study was to investigate the relationship between the GRIm score and short- and long-term outcomes in elderly patients with colon cancer. PATIENTS AND METHODS: Patients aged ≥75 years who underwent colectomy between 2008 and 2019 were eligible for the study. Patients were divided into high GRIm (score 1-3) and low GRIm (score 0) groups. RESULTS: A total of 430 patients were enrolled (high GRIm, n=126; low GRIm, n=304). A high GRIm score was an independent predictive factor for postoperative complications [odds ratio=4.146; 95% confidence interval (CI)-2.536-6.777; p<0.001]. The median follow-up was 42 months (range=1-160 months). Five-year relapse-free (79.3% vs. 92.7%; p=0.001), overall (76.0% vs. 92.2%, p=0.001), and non-cancer-specific (84.7% vs. 94.6%, p=0.003) survival were lower in the high GRIm group. Multivariate analysis revealed a high GRIm score to be an independent predictive factor for poorer overall (hazard ratio=2.875; 95% CI=1.451-5.698; p=0.002) and non-cancer-specific (hazard ratio=3.650; 95% CI=1.612-8.265; p=0.001) survival. CONCLUSION: The GRIm score is useful for predicting postoperative complications and non-cancer cause of death in elderly patients and might be suitable as a surrogate marker for selecting candidates for surgery or perioperative treatment.

Utility of Drain Fluid Culture and Gram Stain in Early Intervention for Occult Anastomotic Leakage in Colorectal Cancer.

BACKGROUND/AIM: Although occult leakage after colorectal surgery does not usually cause critical illness, it can cause long-term complications that decrease the quality of life of patients. There is currently no established diagnostic, treatment, or follow-up method for occult leakage. We assessed the risk factors of occult leakage and examined the efficacy of drain fluid culture and Gram staining for its early detection and appropriate treatment intervention. PATIENTS AND METHODS: Data from 243 consecutive colorectal cancer patients who underwent resection with reconstruction by the double stapling technique between 2016 and 2020 were reviewed. RESULTS: Sixteen (6.6%) patients had postoperative occult leakage. Multivariate analysis revealed that preoperative treatment was significantly associated with occult leakage (odds ratio=12.423; 95% confidence interval=4.095 to 17.680; p<0.001). Among the 16 patients, 1 experienced stenosis, and none experienced a fistula or chronic sinus. Drain fluid samples of 34 patients (14.0%) were Gram stainpositive, and those of 76 patients (31.3%) were culturepositive. The positive and negative predictive values of drain fluid culture were 18.4% and 98.7%, respectively, and those of Gram staining were 38.2% and 98.6%, respectively, for occult leakage. Among cases with occult leakage, more than two bacterial species were detected in 71.5% of the cultures. Antibiograms indicated that the three major species tended to be resistant to cephem antibiotics, which are used for prophylaxis, but susceptible to carbapenem antibiotics, which are used for empiric therapy. CONCLUSION: Drain fluid culture and Gram staining may enable early detection and appropriate treatment intervention for occult leakage.

Transcriptional specificity in various p53-mutant cells.

Mutation of the tumor suppressor gene p53 is the most common genetic alteration observed in human tumors. However, the relationship between the mutation point of p53 and the transcriptional specificity is not so obvious. We prepared Saos-2 cells with various mutations of p53 that are found in human tumors, and examined the resulting transcriptional alterations in the cells. Loss of function and gain of function were observed in all p53 mutants. Hot-spot mutations of p53 are frequently found in tumor cells. We compared hot-spot mutations and other mutations of p53 and found that a more than 2-fold transcription of CADPS2, PIWIL4 and TRIM9 was induced by hot spot mutations, but not by other mutations. As PIWIL4 suppresses the p16(INK4A) and ARF pathway, restraining cell growth and genomic instability, induction of PIWIL4 expression may be one reason why hot-spot mutations are frequently found in tumor cells.