A method for detecting active malignancy in a subject patient, comprising: mixing a labeled hydrophobic probe capable of binding to specific and non-specific hydrophobic binding sites of serum albumin with an aliquot of a first sample of a subject patient's serum albumin-containing extracellular fluid, the amount of probe such that the molar ratio of the probe to the serum albumin is between 2 and 7, the probe optionally comprising two or more substances; mixing a solvent with the aliquot of the first sample, the solvent such that when added to the aliquot and probe the solubility of the probe is increased in the aliquot, and the amount of solvent is sufficient to dissociate a portion of the probe from the serum albumin without causing significant dissociation of hydrophobic metabolites from the serum albumin, the solvent optionally comprising two or more substances; analyzing the mixture of aliquot, probe, and solvent to determine for the first sample one or more binding parameters of the probe, where analyzing the mixture comprises: substantially excluding from the mixture a portion of the probe that is bound on lipoproteins and a portion of the probe that is aggregated into micelles; and determining the one or more probe binding parameters of the sample from the remaining portion of the probe in the mixture; and comparing the one or more binding parameters of the first sample to one or more control binding parameters of a probe binding to serum albumin in the extracellular fluid of at least one of: a cancer-free control patient and a control patient with an active malignancy. mixing a labeled hydrophobic probe capable of binding to specific and non-specific hydrophobic binding sites of serum albumin with an aliquot of a first sample of a subject patient's serum albumin-containing extracellular fluid, the amount of probe such that the molar ratio of the probe to the serum albumin is between 2 and 7, the probe optionally comprising two or more substances; mixing a solvent with the aliquot of the first sample, the solvent such that when added to the aliquot and probe the solubility of the probe is increased in the aliquot, and the amount of solvent is sufficient to dissociate a portion of the probe from the serum albumin without causing significant dissociation of hydrophobic metabolites from the serum albumin, the solvent optionally comprising two or more substances; analyzing the mixture of aliquot, probe, and solvent to determine for the first sample one or more binding parameters of the probe, where analyzing the mixture comprises: substantially excluding from the mixture a portion of the probe that is bound on lipoproteins and a portion of the probe that is aggregated into micelles; and determining the one or more probe binding parameters of the sample from the remaining portion of the probe in the mixture; and substantially excluding from the mixture a portion of the probe that is bound on lipoproteins and a portion of the probe that is aggregated into micelles; and determining the one or more probe binding parameters of the sample from the remaining portion of the probe in the mixture; and comparing the one or more binding parameters of the first sample to one or more control binding parameters of a probe binding to serum albumin in the extracellular fluid of at least one of: a cancer-free control patient and a control patient with an active malignancy.