I am staying in Singapore, planning to hire a helper from India. As part of process got a medical test done for her in India and in X-RAY chest PA report Radiologists impression is given as "Right Apical Fibrosis".
What does that mean? How serious is that?

There would be mandatory medical tests done in Singapore once she arrives and should sent back if anything serious comes out of test reports. So it is necessary to ensure that she is fine and healthy before travel.