Mercury cadmium telluride Hg1-xCdxTe, x < ~ 0.16 semiconductors demonstrate inverted band structure ordering which corresponds to the topological phase. The conduction band and the heavy hole subband touch each other providing a gapless state in the whole composition range 0 < x < 0.16. The direct band structure with the positive energy gap is realized at x > 0.16 (the trivial state). In contrast to the most of 3D topological phases, the free carrier concentration in Hg1-xCdxTe topological phase is low enough to observe the photoconductivity effect in the terahertz spectral range. In this work, we present our experimental results on the photoconductivity excited by terahertz laser pulses in Hg1-xCdxTe epitaxial films in a close vicinity to the band inversion point. We have observed the positive and the negative photoconductivity effects in the absence of the magnetic field in the samples with the inverted and the direct energy spectrum, respectively. We demonstrate that, for the topological phase, the photoresponse is an uneven function of the magnetic field applied. This behavior is atypical for the conductivity and photoconductivity, which normally do not depend on the magnetic field polarity. This may be considered as breaking of the T-symmetry in the photoconductivity. Moreover, the mirror-like potential probes across the sample demonstrate a non-even behavior in magnetic field as well, which may be regarded as breaking of the P-symmetry. At the same time, reversing of the magnetic field direction and the position of the otential probes simultaneously does not affect the photoconductivity demonstrating thus the PT-symmetry. It should be noted that the equilibrium magnetoresistance, as well as photoconductivity in the trivial phase are even functions of the magnetic field, as it normally is. The possible mechanisms of the positive and negative photoconductivity are discussed.