Minimal residual disease detection defined as the malignant fraction of the total primitive stem cell compartment offers additional prognostic information in acute myeloid leukaemia.

INTRODUCTION: Immunophenotypic detection of minimal residual disease (MRD) in bone marrow (BM) of acute myeloid leukaemia (AML) patients is of high prognostic relevance. Standard MRD percentage is assessed as a percentage of total white blood cells (WBCs) and is therefore highly dependent on WBC count. Peripheral blood (PB) contains more than five times lower MRD percentages. Therefore, PB in BM aspirates cause dilution of the MRD cells, possibly leading to false-negative results for BM MRD. The latter is avoided when relating the fraction of malignant primitive cells, identified by aberrant marker expression [aberrant primitive cells (aPC)], to the total population of primitive cells. Such a fraction may in addition reflect an important biological parameter. METHODS: As this approach is thus independent of WBC count and the total size of the primitive compartment, we investigated the role of aPC fractions on overall and relapse-free survival (RFS) in 98 patients with AML under the age of 60. RESULTS: We show that this approach identifies MRD-negative (as defined by % of WBC) but aPC-positive (as defined by % of primitive cells) patients with poor outcome after both first and second induction cycle of chemotherapy. CONCLUSION: As a result, in cases with a primitive marker present, RFS is best predicted when combining standard MRD percentage with aPC fractions.

No-touch isolation technique in colon cancer: a controlled prospective trial.

In order to assess the effect of the no-touch isolation technique, in the treatment of large bowel cancers, on the site of first recurrence and disease-free and overall survival, 236 patients were prospectively and randomly assigned to either the no-touch isolation technique (117 patients) or to a conventional resection technique (119 patients). No patient with distant metastases or unresectable disease entered the study. The two treatment groups were comparable with regard to patient characteristics. Pre- and postoperative complications (including mortality within 30 days) were similar in both groups. After a complete follow-up of 5 years, a tendency for reduction in the number of, and time to, occurrences of liver metastases was seen in the no-touch isolation group (P = 0.14). This effect was most obvious in the sigmoid colon with angio-invasive growth. Overall (P = 0.42) and corrected (P = 0.25) survival did not differ significantly among the treatment groups although in every analysis the survival data of the no-touch isolation group were superior. The data do suggest a limited benefit of the no-touch isolation technique. This observation is important since the morbidity and mortality of surgery were equal in both groups.

Stapling devices in pulmonary surgery.

The results with the use of mechanical stapling devices (TA 30, 55 and 90) in pulmonary surgery are reviewed. In a series of 171 pulmonary operations, staples were used to close the bronchial stump in 95 cases. Also 100 large pulmonary vessels were closed with the stapling device. No complications were observed that could be ascribed purely to the use of the stapling instruments. Resection of emphysematous bullae was followed by a smooth postoperative course, characterized by an almost complete lack of air leakage. An important advantage of mechanical stapling devices is the rapidity and reliability of bronchial and vascular closure, resulting in decreased operating time and safer operative procedures. To obtain good results with these instruments experience and sound surgical judgment are necessary.