A wireless communication node (10) dynamically estimates passive intermodulation (PIM) interference coupled into the node's receive path from the transmission of a composite signal through the node's transmit path. The node (10) then cancels the estimated PIM interference in the receive path. In some embodiments, the node dynamically estimates the PIM interference as a function of the composite signal that models PIM interference generation and coupling in the node (10) according to one or more coefficients (30). The coefficients (30) may be determined by transmitting a test signal (34) during a test stage, when the node (10) is not scheduled to receive any signal. Later, when the composite signal (18) is transmitted, the node (10) uses the coefficients (10) to dynamically estimate and cancel the resulting PIM interference.