What is drug is given for stage 2 medistanial b cell lymphoma, is hair loss unavoidable?

Depends on subtype. Drug combinations are usually given for b-cell lymphomas in the mediastinum. The particular subtype of lymphoma determines the drug selection. Aggressive lymphomas require chemo drugs that almost always cause hair loss. However, some "low grade" lymphomas appear in the chest and can be treated with drugs that do not require alopecia. However, hair loss is reversible, so make sure rx is curative!