Mild volume loss of mass lesion in TB.

My mother was diagnosed with Pulmonary TB via Genexper Test and AFB culture and also noticed a mass lesion measuring 1.9x2.9x2.2cm (ap x trans x si) and two months completed so far with ATT drugs excluding Pyrazinmide since she had severe toxicity. Now when plain ct is done mass lesion measures 1.7 x 2.7 cm ( ap x trans) with mild reduction in few other tree in bud pattern nodule densities. She has increased appetite, strength compared before treatment occasional cough with on/off sputum. No loss of weight. So my question is, does this mass lesion is of TB or something else? Is mild volume loss is a good sign that lesion is of TB? How much time it takes to reduce in such mass lesion for TB?