Continuing on the issue of heparins potentially improving survival of cancer patients, other studies have suggested a survival benefit for low molecular weight heparin (LMWH) in cancer patients. The Malignancy and Low-Molecular-Weight Hepatin Therapy study (MALT, a bit of a stretch) by Klerk and colleagues (abstract here) enrolled 302 patients with an advanced solid tumor (defined as a cancer that could not be treated curatively) to six weeks of a LMWH called nadroparin/Fraxiparine injected under the skin (subcutaneously, or SC) twice daily, or a placebo injection for six weeks. There was a significant survival difference favoring the recipients of the active drug (median survival 8 vs. 6.6 months, hazard ratio (HR) of 0.75 (25% improvement in survival)) that was more impressive in the patients who had a better prognosis (predicted to have a survival of more than 6 months when they were entered onto the trial) (15.4 vs. 9.4 months, HR 0.64, or 36% improvement in survival):

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Not surprisingly, however, there was also a trend toward an increased number of major bleeds in patients who received blood thinner treatment compared with those on placebo (3% vs. 1%). Read the rest of this entry »

In a prior post we touched on some reasons why heparins, blood thinners that are given IV or under the skin (subcutaneously), may have direct anti-tumor effects that could improve cancer outcomes, and another post covered the mixed results with the oral anticoagulant (blood thinner) coumadin in cancer, most notably SCLC. Heparins are divided into unfractionated heparin, which contains a broad range of proteins that can be quite variable in the degree of blood thinning achieved, is most typically administered as a continuous IV infusion (some settings use unfractionated heparin in a subcutaneous (under the skin) injection), and usually requires at least daily monitoring with lab tests, and low molecular weight heparin (LMWH), which is a more filtered product that produces a more reliable amount of blood thinning activity and, depending on the particular formulation, are given once or twice daily as a subcutaneous injection. Although still requiring injections and quite expensive, the work on heparins over the last several years has indicated that LMWH is as or more effective than unfractionated heparin in treating established blood clots and preventing new ones, and LMWH allows for safe outpatient treatment in many settings (although some situations, such as pulmonari emboli, are still most commonly treated conservatively with inpatient management). This typically resolves once heparin is discontinued. Over the past decade, more and more of the use of unfractionated heparin has switched over to LMWH of one brand or another. Aside from bleeding complications, which are always a risk with blood thinners, 10-20% of patients receiving heparin develop heparin-induced thrombocytopenia (HIT), or low blood counts from heparin, which is an immune-mediated condition in which a person who has been on heparin (most commonly unfractionated heparin, but this can occur with LMWH as well) develops antibodies to heparin that cross-react with platelets, leading to a potentially serious decline in the platelet count in patients who remain on heparin. So there can be negative consequences with these agents, so we’ll need to carefully explore the favorable and unfavorable findings with this class of drugs in cancer management. Read the rest of this entry »