Fuzzy approach toward reducing false positives in the detection of small multiple sclerosis lesions in magnetic resonance images

The large number of false positives that result when automatic algorithms are considered for segmenting small multiple sclerosis lesions in magnetic resonance imaging hampers the posterior evaluation of lesion load. To address this problem we propose a fuzzy system which can improve the differentiation between true and false positive detections in proton density- and T2-weighted images. On the basis of an earlier work, which was focused on the detection of hyperintense regions in MR brain images, the system here presented introduces fuzzy restrictions derived from the regional analysis of the main features in such regions. Results show a reduction to a 3.6% in the number of false detections while preserving most of the true detections obtained using previous algorithm.

A single, double lumen high-flow catheter for patients undergoing peripheral blood stem cell transplantation. Experience at the National Cancer Institute in Mexico

Peripheral blood stem cell transplantation (PBSCT) requires a high-flow catheter for adequate cell collection by apheresis and long i.v. support, this is usually achieved by multiple catheters. We analyzed our experience with Mahurkar or Permacath for apheresis and long-term i.v. support in PBSCT, cared for exclusively by an i.v. therapy team. Fifty-six catheters were used in 53 patients that completed PBSCT (28 Permacath and 28 Mahurkar). In 10 patients (19%) the same catheter was used for multiple PBSCT. The average stay was 58.4 days (7-219), Permacath 76.8 days (14-219) and Mahurkar 42 days (7-106). The incidence of infectious complications was 2.2 x 1000 catheter-days (1.7 Permacath and 3.0 Mahurkar); during neutropenia it was 3.7 x 1000 cathether-days. The incidence of thrombosis was 0.9 x 1000 catheter-days. There was a total of seven infectious episodes (12.7%). Five (9%) were local and two were (3.6%) bacteremias. The microorganism most commonly isolated was Staphylococcus sp. (57%). Four catheters (7.1%) were removed because of complications: one thrombosis and three infections. Both catheters have proven useful and safe for long-lasting vascular access in patients undergoing PBSCT. No statistical difference was found in infectious and non-infectious complications between either catheters.

[Algorithm management for detection of monoclonal gammopathies in serum. Experience of the Instituto Nacional de Cancerología in México]

BACKGROUND

Most patients with multiple myeloma have an abnormal band in the gamma region of protein electrophoresis.

AIM

To correlate the clinical diagnosis with patterns of protein electrophoresis.

METHODS

Retrospective analysis of all protein electrophoresis or immunoglobulin quantification requested during 1992 and review of clinical charts of patients.

RESULTS

During 1992, 553 protein electrophoresis were requested. Of these, 344 were repetitions and 209 came from patients seen for the first time. Among the latter, we found a monoclonal component in 40. Of these 40 patients, 35 had a multiple myeloma, one had a plasmocytoma and four a non-Hodgkin lymphoma. Fourteen patients with diagnosis of myeloma did not have a monoclonal component in protein electrophoresis. These figures resulted in a 71% sensitivity and 97% specificity for monoclonal components in the diagnosis of multiple myeloma. The monoclonal component of patients with myeloma was characterized as IgG in 29 (60%), IgA in 5 (10%) and IgM in one.

CONCLUSIONS

A monoclonal component present in a protein electrophoresis has a high diagnostic accuracy for multiple myeloma.

A randomized study of mitoxantrone plus cytarabine versus daunomycin plus cytarabine in the treatment of previously untreated adult patients with acute nonlymphocytic leukemia

Between May 1985 and November 1988, 143 adult patients with previously untreated acute nonlymphocytic leukemia were randomized to receive mitoxantrone and cytarabine (MTT+Ara-C) or daunomycin and cytarabine (DNM+Ara-C) in order to compare the efficacy and acute and chronic toxicities. Therapy consisted of 3 days of MTT 12 mg/m2/i.v. or DNM 45 mg/m2/i.v.; both groups received Ara-C 100 mg/m2 daily by continuous infusion (CI) for 7 days. Those who failed to achieve a complete remission after one induction course received a second induction course for 2 and 5 days at the same doses. All the patients who achieved complete remission received two consolidations of 2 days of MTT or DNM and 5 days of Ara-C in CI at the same dose as for induction. Of the 72 patients on MTT+Ara-C, 38 (53%) achieved complete remission, compared with 29 (43%) of 67 treated with DNM+Ara-C. Three and 5 patients had partial remission, 7 and 18 failed to respond, 24 and 15 died in the first 21 days of induction, of those treated with MTT+Ara-C or DNM+Ara-C, respectively (p = 0.34). Median duration of complete remission and survival was 185 and 103 days or 165 and 160 days, respectively (p = 0.85). More early deaths were observed with MTT+Ara-C due to greater myelosuppression, and a higher incidence of failure with DNM+Ara-C. No significant differences between treatment groups were observed in 21 categories of adverse events. The results demonstrate similar incidence of complete response, length of duration of complete remission, overall survival, and toxicity with MTT+Ara-C and DNM+Ara-C.