How would you treat an elderly patient with CD30 negative PTCL NOS involving base of tongue, vallecula and bilateral cervical lymph nodes?

This appears to be a stage II PTCL, NOS. Involvement of the tonsils, base of the tongue, and surrounding lymphoid tissue is considered nodal disease. If there is true involvement of the airway then it may be called "extranodal", but the treatment remains unchanged.

Randomized studies are lacking/limited in CD30 negative peripheral T-cell lymphomas (see Wulf et al., ACT-2 trial), but for this patient, I would use CHOP every 21 days and aim to complete 6 cycles of therapy if disease is responsive, ...