If a stage I laryngeal cancer completely responds to FU-based chemotherapy (given for another malignancy) would you consider observation?  

We expect 60-80% response rate with induction chemo data with 20% having complete response. That doesn’t preclude local treatment but predicts for better outcome

Holding RT and following early stage laryngeal cancer seems like a risky proposition. You have a high likelihood of a favorable outcome with microscopic residual disease treated with small field definitive radiotherapy. The late toxicities are low with RT for early glottic cancer and it’s a re...

2019-03-03 Addendum: 10 yr update of Univ. Paris results using CTX alone for N0M0 larynx and pharynx SqCCa. Please see new reference below.Laccourreye, O et al. Ten-year outcome of curative "exclusive" chemotherapy in N0M0 SqCCa of the larynx and pharynx with complete clinical response. Head and Nec...

No.  I would irradiate.  Jim Parsons (UF alumni) used to say a "CR is only half way to a C-U-R-E."