F.N. Hayek

Background: Tacrolimus (FK) is usually given as a continuous 24-hour infusion for acute graft-vs-host disease (GVH) prophylaxis in the setting of allogeneic hematopoietic stem cell transplantation (HSCT). Often, this schedule becomes logistically difficult and requires dedicated line and monitoring. We report our experience with the use of twice-daily intravenous (IV) bolus injection. Patients and Methods: Between 01/00–06/04, 59 patients (pts) with hematologic indication for allogeneic HSCT received twice-daily FK for GVH prophylaxis. Patients were given FK at initial dose of 0.015 mg/kg IV bolus over 3 hours on day T −1 then every 12 hours. First trough level was drawn before the seventh dose on day T +2 and then twice weekly unless clinically indicated otherwise. Doses were adjusted for a target level of 10 ng/ml (range 5–20 ng/ml). Patients were switched to oral form when were clinically able to tolerate it. Results: Median age was 49 years (range 19–64 y). Donors were transplanted for hematologic disorder indications. Donor compatibility status was as follows: matched-related 38 (64.4%), matched-unrelated 10 (17%), and mismatched-related 11 (18.6%). FK was used in 2 GVH prophylaxis protocols: with methotrexate or in combination with mycophenolate mofetil and daclizumab. Median first trough level was 9 ng/ml (range 2.6–22.5). Rate of grade I or II acute GVH was 16.9%. Only one pt developed grade III (1.7%) and no pt had grade IV. Significant nephrotoxicity (peak creatinine level ≥2× baseline or ≥2 mg/dl) occurred in 16 patients (27.1%). Five of these pts (31.25%) had at least 1 FK trough level ≥20 ng/ml whereas 15 of 44 patients with normal renal function (34.1%) had such elevated levels. Severe nephrotoxicity requiring dialysis occurred in 4 pts and only 1 of these had elevated FK level. One pt developed HUS/TTP and had all FK trough levels <20 ng/ml. There were no grade 3 or 4 seizures or tremors. Median discharge day was T +19 (range 12–34). Two pts relapsed, but were alive, by day 100. Day-100 relapse-free mortality was 18.6%. Conclusion: Results of twice-daily bolus tacrolimus compare favorably to historical safety and efficacy data of continuous infusion of FK in allogeneic HSCT. Bolus infusion was easy to administer and adjust and did not correlate with increased risk of nephrotoxicity. These results should be further investigated in a prospective clinical trial. Background: Tacrolimus (FK) is usually given as a continuous 24-hour infusion for acute graft-vs-host disease (GVH) prophylaxis in the setting of allogeneic hematopoietic stem cell transplantation (HSCT). Often, this schedule becomes logistically difficult and requires dedicated line and monitoring. We report our experience with the use of twice-daily intravenous (IV) bolus injection. Patients and Methods: Between 01/00–06/04, 59 patients (pts) with hematologic indication for allogeneic HSCT received twice-daily FK for GVH prophylaxis. Patients were given FK at initial dose of 0.015 mg/kg IV bolus over 3 hours on day T −1 then every 12 hours. First trough level was drawn before the seventh dose on day T +2 and then twice weekly unless clinically indicated otherwise. Doses were adjusted for a target level of 10 ng/ml (range 5–20 ng/ml). Patients were switched to oral form when were clinically able to tolerate it. Results: Median age was 49 years (range 19–64 y). Donors were transplanted for hematologic disorder indications. Donor compatibility status was as follows: matched-related 38 (64.4%), matched-unrelated 10 (17%), and mismatched-related 11 (18.6%). FK was used in 2 GVH prophylaxis protocols: with methotrexate or in combination with mycophenolate mofetil and daclizumab. Median first trough level was 9 ng/ml (range 2.6–22.5). Rate of grade I or II acute GVH was 16.9%. Only one pt developed grade III (1.7%) and no pt had grade IV. Significant nephrotoxicity (peak creatinine level ≥2× baseline or ≥2 mg/dl) occurred in 16 patients (27.1%). Five of these pts (31.25%) had at least 1 FK trough level ≥20 ng/ml whereas 15 of 44 patients with normal renal function (34.1%) had such elevated levels. Severe nephrotoxicity requiring dialysis occurred in 4 pts and only 1 of these had elevated FK level. One pt developed HUS/TTP and had all FK trough levels <20 ng/ml. There were no grade 3 or 4 seizures or tremors. Median discharge day was T +19 (range 12–34). Two pts relapsed, but were alive, by day 100. Day-100 relapse-free mortality was 18.6%. Conclusion: Results of twice-daily bolus tacrolimus compare favorably to historical safety and efficacy data of continuous infusion of FK in allogeneic HSCT. Bolus infusion was easy to administer and adjust and did not correlate with increased risk of nephrotoxicity. These results should be further investigated in a prospective clinical trial.

Regional anaesthesia for carotid artery surgery allows the patient to remain awake so that the neurological status can be assessed during cross-clamping. However, this technique is unfamiliar to many anaesthetists and, even in experienced hands, failure may occur [1, 2]. We describe a simple modified technique based on a three-injection technique as described by Moore [3]. The patient is placed in the semi-sitting position with their head turned slightly away from the side to be blocked. The transverse processes of C2, C3 and C4 are located approximately 1 cm posterior to the posterior border of the sternomastoid muscle, and intradermal infiltration of lidocaine 1% 0.25 ml for each level is performed. The deep cervical plexus block is performed using a short-bevelled needle (50 mm-Stimuplex; B Braun, Melsungen, Germany) connected to a nerve stimulator (Stimuplex DIG, B Braun), and the needle inserted perpendicular to the skin, aiming in a slightly caudal direction at the C2 level to elicit neck muscle contractions. The same technique is repeated at C3 and C4. The tip of the needle is considered to be correctly positioned when a current intensity of 0.5 mA elicits a neck muscle response. Five ml of local anaesthetic mixture (bupivacaine 0.5% and lidocaine 2%) is injected over 2–3 min after a negative aspiration test. The technique is completed by performing a superficial cervical plexus block by infiltration at the midpoint of the sternomastoid muscle with 7 ml of the same mixture and infiltration of 3–5 ml of local anaesthetic mixture along the inferior border of the mandible to block the afferent branches from the cranial nerves. This injection along the mandible appears to reduce the pain associated with prolonged use of a retractor. We have found that patients are rarely distressed or uncomfortable during performance of these blocks. We have obtained excellent results with this technique in a number of patients and further evaluation is ongoing. The use of a nerve stimulator for deep cervical plexus blockade has been previously reported for carotid surgery. Mehta and Juneja [4] and Merle et al. [5] used a single-injection technique, guided by a nerve stimulator. In both reports the technique was not completely successful and required supplemental intravenous analgesia or local anaesthetic infiltration, particularly during retractor placement and carotid artery dissection. In our technique, the identification of nerves of the cervical plexus was more precise, requiring neck muscle contraction prior to each of the three injections. Phrenic nerve palsy is frequent (up to 90%) after deep cervical plexus block. The use of a nerve stimulator can elicit a diaphragmatic muscle response which helps to avoid the administration of the local anaesthetic directly into the area of the phrenic nerve. It has been reported that the use of a nerve stimulator decreases the peak serum concentration (Cmax) and significantly slows the time to reach peak concentration (Tmax) of the local anaesthetic [5], both of which are major determinants of systemic toxicity.

Abstract Viable eukaryotic cells shed circular membrane fragments called microvesicles (MV) from the cell surface and secrete them from the endosomal compartments. These MV, which are different from apoptotic bodies, are enriched in lipids, proteins and mRNA. We postulate that MV play an important and underappreciated role in cell-cell communication by i) stimulating target cells with ligands that the MV express, ii) fusing with target cells and thus transferring various receptors to their surface, and iii) delivering mRNA, lipids and proteins. Since tumor cells secrete large quantities of MV we hypothesized that the latter are important constituents of the tumor microenvironment and their role in tumor progression merited investigation. First, we observed that human and murine lung cancer cell lines secrete more MV in response to non-apoptotic doses of hypoxia, irradiation and chemotherapy. The MV derived from human cancer cells chemoattracted bone marrow-, lymph node- and lung-derived fibroblasts and endothelial cells and activated in these stromal cells the phosphorylation of MAPKp42/44 and AKT. Furthermore, they also induced in bone marrow- and lung-derived fibroblasts expression of LIF, OSM, IL-11, VEGF and MMP-9. Moreover, conditioned media from marrow fibroblasts exposed to MV induced phosphorylation of STAT-3 proteins and chemoattracted lung cancer cells in a LIF- and OSM-dependent manner and, together with IL-11 and VEGF, activated osteoclasts and endothelial cells. Furthermore, MV from cancer cells embedded in Matrigel implants strongly stimulated angiogenesis. We also found that tumor-derived MV express tissue factor (TF) and activate platelets and as a result of this MV derived from activated platelets transfer several adhesion molecules from platelets to the tumor cell surface. This increases adhesiveness of lung cancer cells in endothelium and their metastatic spread in vivo after injection into syngeneic mice. Finally, we found that formation of MV depends on the formation of membrane lipid rafts. Thus we postulate that tumor- and platelet-derived MV are underappreciated constituents of the tumor microenvironment and play a pivotal role in tumor progression/metastasis and angiogenesis. As MV formation appears to be lipid raft-dependent, we suggest that inhibitors of membrane lipid raft formation (e.g, statins or polyene antibiotics) could decrease MV-dependent tumor spread/growth and we are currently testing this hypothesis in animal models in vivo.

Primary plasma cell leukemia (PPCL) is a rare subtype of multiple myeloma that follows a rapid clinical course and responds poorly to conventional myeloma treatment. Recently it has been shown that melphalan doses up to 140 mg/m2 without HPC support can be given safely to myeloma patients. We report our experience with the use of HDM without HPC support in 3 patients with PPCL. All patients received HDM (140 mg/m2) as a single 40-minute IV infusion. Filgrastim (6 g/kg/day) was started 24 hours after HDM and continued until absolute neutrophil count (ANC) was> 500/L. There was complete clearance of plasma cells from the bone marrow and resolution of cytogenetic abnormalities. IgG level in patient 1 and M-protein level in patients 2 and 3 decreased by> 75% before thalidomide initiation and was maintained for> 6 weeks. One patient (case 1) had extramedullary disease progression evidenced on day 130 and expired despite further treatment with VAD, arsenic trioxide, methylprednisolone, and thalidomide. Patient 2 achieved CR after receiving allogeneic stem cell transplantation from a matched sibling donor at day 137 and remains in complete remission. There was no treatment-related mortality. Treatment of PPCL with HDM without HPC support was well tolerated. It resulted in prompt hematologic recovery and produced dramatic control of an otherwise rapidly fatal process. Such treatment may be a viable option when HPC transplantation is not feasible. Table 1Patient characteristicsAge (y)/SexWBC (1000/μl)/BM Involve-mentM-protein Level (g/dl)/Ig TypePrior Rx/ResponseCount Recovery (D 0+)Thalido-mide Started (D 0+)Best Documented Response/Day (D 0+)TTP/Survival (Days)50/M60.5/100%Not available/IgGHigh-dose cortico-steroids/progres-sive disease20NAPR/120130/423+45/F54.6/100%3.54/IgGHigh-dose cortico-steroids/Progres-sive disease2030PR/30NA/557+66/F17.3/75%4.5/IgGVAD/progres-sive disease36100PR/164NA/219+TTP: time to progression, NA: not applicable, PR: partial response. Open table in a new tab TTP: time to progression, NA: not applicable, PR: partial response.