Cisplatin-induced hyperglycemic hyperosmolar coma.

We present a case of severe hyperglycaemic hyperosmolar derangement after treatment with cisplatin in a patient without previous diabetes mellitus. Limited data are available on this adverse reaction, explaining why impaired glucose handling due to cisplatin is not generally recognised.

Doxorubicin potentiates TRAIL cytotoxicity and apoptosis and can overcome TRAIL-resistance in rhabdomyosarcoma cells.

Doxorubicin (DOX) and ifosfamide (IFO) are the most active single agents in soft tissue sarcomas (STS). Tumour necrosis factor-alpha (TNF-alpha) is used for STS in the setting of isolated limb perfusions. Like TNF-alpha, TNF-related apoptosis-inducing ligand (TRAIL) induces apoptosis. In contrast to TNF-alpha preliminary studies suggest that TRAIL lacks systemic side effects. The effects of TRAIL alone and in combination with DOX or 4-hydroxy-IFO were evaluated in the TNF-alpha sensitive rhabdomyosarcoma cell line KYM-1, its 5-fold TNF-alpha sensitive subline KD4 and its >150-fold TNF-alpha resistant subline 37B8R. Membrane expression of TRAIL-receptors DR4 (death receptor 4), DR5 (pro-apoptotic), DcR1 (decoy receptor 1), DcR2 (anti-apoptotic) was assessed by flow cytometry. Cytotoxicity was determined by microculture tetrazolium assays. Apoptosis assays were performed with acridine orange. DOX (doxorubicin) and 4-OH-IFO decreased survival in all cell lines; a 2-fold resistance was observed for both drugs in 37B8R. All cell lines expressed DR4 and DR5, but hardly any DcR1 or DcR2. TRAIL was cytotoxic in KYM-1, even more in KD4 and induced massive apoptosis; 37B8R was >500-fold resistant to TRAIL and little apoptosis could be observed. TRAIL plus DOX showed synergistic cytotoxicity in KYM-1 and 37B8R. TRAIL plus 4-OH-IFO showed addition in all three cell lines. DOX plus TRAIL-induced more cytotoxicity and apoptosis in all cell lines compared to TRAIL alone. In 37B8R, DOX overcame resistance to TRAIL. In KYM-1, KD4 and 37B8R, sensitivity and resistance to TNF-alpha and TRAIL parallels. TRAIL-resistance was independent from expression of TRAIL-receptors. DOX with TRAIL could overcome TRAIL-resistance in 37B8R cells.

Expression of multidrug resistance proteins, P-gp, MRP1 and LRP, in soft tissue sarcomas analysed according to their histological type and grade.

The biological behaviour of different histological types and grades of soft tissue sarcomas (STS) varies. This might result in a differing sensitivity to cytotoxic drugs. Cross-resistance to functionally and structurally distinct natural-product drugs, known as multidrug resistance (MDR), is associated with the overexpression of P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1) and lung resistance-related protein (LRP). The purpose of this study was to evaluate the expression of P-gp, MRP1 and LRP in STS according to their histological type and grade. In 141 chemotherapy-naive STS patients, the expression of the three MDR proteins was detected by immunohistochemistry. Nine histological types were documented. These were 19% grade 1, 34% grade 2 and 47% grade 3 tumours. Expression of P-gp and LRP was observed more frequently than the expression of MRP1 (P<0.0001). P-gp expression was most pronounced in malignant fibrous histiocytoma (MFH), but was low in leiomyosarcomas. MRP1 was expressed in most malignant peripheral nerve sheath tumours (MPNST). LRP was strongly expressed in MFH and unspecified sarcomas, but was low in liposarcomas. MRP1 and LRP expression was significantly more common in grades 2 and 3 compared with grade 1 tumours. P-gp expression was correlated with MRP1, especially in grade 3 STS. In conclusion, P-gp, MRP1 and LRP are expressed in the majority of STS, but this expression varies according to the histological type. MRP1 and LRP, but not P-gp expression, were found to be correlated to tumour grade. MDR might contribute to the observed differences in clinical behaviour within the heterogeneous group of STS.

Expression of multidrug resistance-associated proteins in rhabdomyosarcomas before and after chemotherapy: the relationship between lung resistance-related protein (LRP) and differentiation.

Rhabdomyosarcomas generally respond well to chemotherapy, and the residual lesions often are better differentiated than their primaries. This phenomenon may be explained by selective multidrug resistance (MDR) of differentiated tumor cell populations. We assess the role of MDR proteins in chemotherapy-induced differentiation in rhabdomyosarcomas in a clinical setting. Paraffin-embedded samples of 13 pairs of primary untreated rhabdomyosarcomas and their residual, recurrent, or metastatic lesions after chemotherapy were assessed for expression of MDR proteins, including P-glycoprotein (Pgp), multidrug resistance-associated protein (MRP-1), and lung resistance-related protein (LRP). Expression was semiquantitatively scored based on the percentage of isolated immunoreactive tumor cells as follows: 0, negative; 0.5, <5%; 1, 5% to 25%; 2, 26% to 50%; 3, 51% to 75%, and 4, >75%. All specimens after chemotherapy, except the late recurrences, were better differentiated than their primary, untreated specimens. Pgp or MRP-1 expression did not change significantly, but LRP expression increased significantly after chemotherapy. In both untreated and treated samples, LRP was expressed primarily in differentiated cells. The findings indicate that the in vivo expression of LRP, but not of Pgp and MRP-1, is induced by chemotherapeutic treatment in rhabdomyosarcomas. The preferential expression of LRP in differentiated cells and the subsequent more extensive expression after chemotherapy suggests that LRP plays a role in therapy-induced differentiation.

Continuous leakage measurement during hyperthermic isolated limb perfusion.

BACKGROUND: Continuous measurement of perfusate leakage into the systemic circulation is of the utmost importance and can be performed with the help of radioactive tracers. The purpose of this study was to assess changes in the perfusion leakage rate between two periods: 1977-1990 and 1991-2000, and to determine the factors responsible for these changes. METHODS: During the 1991-2000 period, 119 patients underwent HILP mainly for locally recurrent melanoma or locally advanced soft tissue sarcoma. HILP was performed with melphalan (33%) or in combination with TNFalpha (65%). There were 67 iliacal, 12 femoral, 25 popliteal, and 15 axillary perfusions performed. Leakage into the systemic circulation was monitored continuously with the help of 131I-albumin and a stationary scintillation detector placed above the heart. RESULTS: The median maximum leakage was 2.7% (range 0%-21%) which is significantly less than the previous period (1977-1990) where leakage of 8% (range 0%-30%) was reported (P < .05). A statistical difference in leakage was detected among perfusion locations where the iliac and femoral vessels showed more leakage than the axillary and popliteal vessels (P < .05). Furthermore, there appeared to be significantly less leakage when TNFalpha was used than when melphalan was the sole drug (P < .05). CONCLUSIONS: Nowadays leakage from isolated perfusions into the systemic circulation is further minimized compared with the days when melphalan was the sole drug used. Increased awareness about TNFalpha leakage, continuous external monitoring with 131I-albumin as the main isotope, flow rate regulation in the perfusion circuit, and regulation of the patient's systemic blood pressure have all been major contributors to this improvement.

Expression of P-glycoprotein, multidrug resistance-associated protein 1, and lung resistance-related protein in human soft tissue sarcomas before and after hyperthermic isolated limb perfusion with tumor necrosis factor-alpha and melphalan.

BACKGROUND: Multidrug resistance (MDR) is associated with expression of P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1), and lung resistance-related protein (LRP). Tumor necrosis factor (TNF-alpha) is able to modify the expression of these three proteins in different cell types. The effect of TNF-alpha in the clinical situation on patients with soft tissue sarcomas (STS) is indeterminate. METHODS: Thirty-seven patients with a locally advanced extremity STS underwent hyperthermic isolated limb perfusion (HILP) with TNF-alpha and melphalan; 15 patients received additional interferon gamma. Clinical and histologic responses were documented and used to define the overall response. Samples before and after HILP were analyzed immunohistochemically for P-gp, MRP1, and LRP. Samples were scored as negative or positive (< or = 5% or > 5% positive tumor cells). RESULTS: Six patients had an overall complete response, 25 patients had a partial response, and 4 patients with STS revealed no change; in 2 patients, the response remained unclear. The percentage STS samples that were positive for all three proteins dropped from 92% before HILP to 85% after HILP. P-gp positive samples were encountered more often than MRP1 positive samples (P < 0.05). The percentage of samples that were negative for all three MDR proteins increased after HILP from 6% to 16%. MDR status had no significant correlation with tumor response. CONCLUSIONS: HILP with TNF-alpha and melphalan results in excellent overall tumor response in patients with locally advanced STS. STS more often are positive for P-gp than for MRP1. MDR status in patients with STS is not predictive for tumor response after HILP. Data from the current study suggest that the combination of TNF-alpha and melphalan does not induce MDR positive STS: a result with clinical importance when consecutive, adjuvant, doxorubicin-containing chemotherapy is considered.

[Hemodynamic and ventilatory complications of mechanical ventilation with high intrinsic positive end-expiratory pressure]. / Hemodynamische en ventilatoire complicaties van beademing met hoge intrinsieke positieve eindexpiratoire druk.

In three mechanically ventilated patients ventilatory and circulatory complications resulted from high levels of intrinsic positive end-expiratory pressure (PEEPi): progressive pulmonary hyperinflation due to impairment of the expiration. PEEPi was initially not considered as the cause of shock and low tidal volumes and/or high inflation pressures. In a 74-year-old man the circulation deteriorated further when hand bagging was started in an attempt to improve his ventilatory condition; after reduction of the respiration rate, he recovered well. In a 40-year-old woman with relapsing polychondritis sedation helped to reduce the respiratory rate so as to restore sufficient expiratory time. A 59-year-old woman developed acute exacerbation of severe chronic obstructive pulmonary disease, and went into shock during interhospital ambulance transport; she was stabilized after recognition of PEEPi and adjustment of the setting of the ventilator. Detection of PEEPi (e.g. by the finding of a deep inflation level on physical examination) is more important than exact measurement of PEEPi. If PEEPi is detected, the ventilator should be set at PEEP at 80-90% of PEEPi, low frequency (e.g. 8/min) and a long expiratory time, and high inspiratory flow.