Separation of lymphoid and myeloid blasts in the mixed blast crisis of chronic myelogenous leukemia: no evidence for Ig gene rearrangement in CALLA-positive blasts

Recent studies suggest that lymphoid blast crisis cells of chronic myelogenous leukemia (CML) expressing the common acute lymphoblastic leukemia antigen (CALLA) are B precursor cells, based on the demonstration of immunoglobulin (Ig) gene rearrangement similar to common acute lymphocytic leukemia. There is little evidence to suggest whether the cells with similar lymphoid characteristics in the mixed blast crisis of CML are also committed to B cell lineage. A patient in "mixed" blast crisis of CML was studied. On the basis of morphology, cytochemistry, and immunological studies, the blasts were classified as having either lymphoid or myeloid characteristics. A proportion of the leukemic blasts expressed CALLA, whereas others expressed My7 antigen. In order to characterize both populations of cell further, CALLA+ blasts and My7+ (myeloid) blasts were isolated by fluorescence-activated cell sorting. The My7+ cells were highly proliferative in cell culture blast colony assays, retained the Ph1 chromosome, and were indistinguishable from acute myelogenous leukemia blasts. The CALLA+ cells were also Ph1-chromosome positive, but in contrast, were poorly proliferative in vitro. Of particular note was their retention of germline configuration of Ig genes, thus distinguishing them from blasts in the lymphoid crisis of CML. We conclude that the lymphoid component in mixed blast crisis may represent a stage of differentiation prior to commitment to B lineage.     

Laparoscopic appendectomy in young female patients: Should we remove the normal-looking appendix?

Objective : This study evaluated whether a significant reduction in unnecessary appendectomies is possible by performing diagnostic laparoscopy before appendectomy in female patients of child-bearing age, leaving behind the normal-looking appendix. Materials and methods : Sixty-one consecutive female patients between the ages of 15 and 45 years with clinical diagnosis of acute appendicitis were studied prospectively. Diagnostic laparoscopy was performed to detect whether the appendix was inflamed. The appendix was then removed and the result of laparoscopic diagnosis was matched with histological diagnosis. Results : Ten out of the 42 laparoscopically diagnosed appendicitis cases had normal appendices on histological examination. Six out of the 19 laparoscopically diagnosed normal appendices had histological evidence of appendicitis. The sensitivity of laparoscopy was 84% and the specificity was 56.5%. Conclusions : Discrepancies existed between laparoscopic appearance and histological examination in acute appendicitis. The appendices of all those with clinically suspected appendicitis should be removed and sent for histological confirmation.      

Small bowel obstruction following low anterior resection: the impact of diversion ileostomy

Background The incidence of small bowel obstruction following rectal cancer surgery has not been well documented in the era of sphincter-preserving surgery. This report aimed to study the incidence, aetiologies and outcomes of small bowel obstruction in patients after low anterior resection for rectal cancer. The factors that might affect the incidences of small bowel obstruction were analysed.Methods Consecutive patients who had undergone low anterior resection for rectal cancer from August 1993 to March 1999 were studied. Patients with unplanned admissions, with the diagnosis of small bowel obstruction, were reviewed. The aetiologies and outcome of small bowel obstruction were documented.Results Two hundred and fourteen patients were included, with a median follow-up time of 39 months; 22 patients presented with 30 episodes of small bowel obstruction, and operations were necessary in nine patients (40.9%). Malignant obstruction occurred in two patients (10.3%). Obstruction within 6 weeks of surgery (including closure of stoma) occurred in 13 patients (6.1%). Early obstruction occurred at a higher incidence in those patients who had had an ileostomy than in those who did not (9.1% vs 2.9%, P=0.048).Conclusion Small bowel obstruction following rectal cancer surgery occurred in 10.3% of patients. The majority of the obstruction was benign in nature. The presence of diversion ileostomy was associated with an increased incidence of early obstruction, and the use of loop ileostomy for proximal diversion should be further assessed.     

Abdominal drainage after hepatic resection is contraindicated in patients with chronic liver diseases

OBJECTIVE: The aim of this study was to determine whether abdominal drainage is beneficial after elective hepatic resection in patients with underlying chronic liver diseases. SUMMARY BACKGROUND DATA: Traditionally, in patients with chronic liver diseases, an abdominal drainage catheter is routinely inserted after hepatic resection to drain ascitic fluid and to detect postoperative hemorrhage and bile leakage. However, the benefits of this surgical practice have not been evaluated prospectively. PATIENTS AND METHODS: Between January 1999 and March 2002, 104 patients who had underlying chronic liver diseases were prospectively randomized to have either closed suction abdominal drainage (drainage group, n = 52) or no drainage (nondrainage group, n = 52) after elective hepatic resection. The operative outcomes of the 2 groups of patients were compared. RESULTS: Fifty-seven (55%) patients had major hepatic resection with resection of 3 Coiunaud's segments or more. Sixty-nine (66%) patients had liver cirrhosis and 35 (34%) had chronic hepatitis. Demographic, surgical, and pathologic details were similar between both groups. The primary indication for hepatic resection was hepatocellular carcinoma (n = 100, 96%). There was no difference in hospital mortality between the 2 groups of patients (drainage group, 6% vs. nondrainage group, 2%; P = 0.618). However, there was a significantly higher overall operative morbidity in the drainage group (73% vs. 38%, P < 0.001). This was related to a significantly higher incidence of wound complications in the drainage group compared with the nondrainage group (62% vs. 21%, P < 0.001). In addition, a trend toward a higher incidence of septic complications in the drainage group was observed (33% vs. 17%, P = 0.07). The mean (+/- standard error of mean) postoperative hospital stay of the drainage group was 19.0 +/- 2.2 days, which was significantly longer than that of the nondrainage group (12.5 +/- 1.1 days, P = 0.005). With a median follow-up of 15 months, none of the 51 patients with hepatocellular carcinoma in the drainage group developed metastasis at the drain sites. On multivariate analysis, abdominal drainage, underlying liver cirrhosis, major hepatic resection, and intraoperative blood loss of >1.5L were independent and significant factors associated with postoperative morbidity. CONCLUSION: Routine abdominal drainage after hepatic resection is contraindicated in patients with chronic liver diseases.     

Delayed portal vein thrombosis after experimental radiofrequency ablation near the main portal vein

BACKGROUND: Portal venous blood flow may protect adjacent tumour cells from thermal destruction with radiofrequency ablation (RFA). This study aimed to investigate the local effect of RFA on the main portal vein branch, and the completeness of cellular ablation in its vicinity, with or without a Pringle manoeuvre using a porcine model. METHODS: This was an in vivo study on 23 domestic pigs. RFA using a cooled-tip electrode was performed 5 mm from the left main portal vein branch under ultrasonographic guidance for 12 min with (n = 10) or without (n = 10) a Pringle manoeuvre. Ten pigs were killed 4 h after the procedure to study the early effects of RFA and ten others were killed 1 week later to determine any delayed effect. As a control, sham operations with a Pringle manoeuvre for 12 min were performed on three pigs. The flow velocity changes of portal vein and hepatic artery were measured using Doppler ultrasonography, and the completeness of cellular ablation around the portal vein was assessed qualitatively by histochemical staining and quantitatively by measuring intracellular levels of adenosine 5'-triphosphate (ATP). RESULTS: In the absence of the Pringle manoeuvre, there was no significant change in mean(s.d.) portal vein flow velocity before RFA (20.0(3.5) cm/s) and at 4 h (18.5(2.5) cm/s) (P = 0.210) and 1 week (19.5(2.2) cm/s) (P = 0.500) after the procedure. Gross and histological examination of the portal vein branches showed no damage without the Pringle manoeuvre. In all pigs that underwent RFA with a Pringle manoeuvre, the portal vein was occluded 1 week after the operation; histological examination of the affected portal vein showed severe thermal injury and associated venous thrombosis. The local effect of RFA on the hepatic artery was similar. With intact portal blood flow during RFA, complete ablation of liver tissue around the pedicle was demonstrated by histochemical staining and measurement of the intracellular ATP concentration. CONCLUSION: RFA was safe when applied close to the main portal vein branch without a Pringle manoeuvre, with complete cellular destruction. Use of the Pringle manoeuvre resulted in delayed portal vein and hepatic artery thrombosis and injury to the hepatic artery and bile duct.     

Acute coronary syndromes

The first 150 words of the full text of this article appear below. Key points Coronary artery disease accounts for >30% ofdeaths in Western society. The diagnosis of myocardial infarctionshould be qualified by size, causation and time from occurrence. Mortalityis reduced by immediate or ‘primary’ percutaneouscoronary intervention or thrombolysis within the first 24 hof onset of ST-segment elevation myocardial infarction. Strategiesto reduce platelet activation (glycoprotein IIb/IIIa receptorantagonists, or clopidogrel) are now recommended in the treatmentof high-risk non-ST-segment myocardial infarction/unstable angina. Elevatedserum troponins may be the result of non-ischaemic myocardialdamage, especially in critical illness.