Preliminary investigation of human lung cancer cells' interaction with millimeter wavelength electromagnetic waves was carried out. The irradiation was performed in vitro by sweeping in frequency in the range 75-110 GHz (W-band), for different exposition times. Frequency spectra of the reflected signal were analyzed and compared for different exposure times. Also, a statistical analysis of the cell populations obtained by microscope imaging was performed. The following effects were observed: 1) retraction of the mean size of the population under irradiation; 2) appearance of the population of large cells (“monsters”); 3) formation of multi-nuclear (polyploidy) cells; 4) dependence of power absorption on the exposition time.