It is described a tissue anomaly detection apparatus (1000) comprising: a probe transmitter device (2) structured to radiate a radio-frequency signal (SRAD) to irradiate a patient tissue in near-field conditions ; the probe transmitter device (2) being provided with: an antenna radiating element (12) configured to radiate the radio-frequency signal with a linear polarization (E) and an actuator (13) mechanically coupled to the antenna radiating element (12) to cause a rotation of the antenna radiating element so as to rotate the polarization of the radiofrequency signal.