Sixteen percent of the patients had laryngeal cancer, 77%
had pharyngeal cancer, of which 51% were p16 positive oropharynx carcinoma. Seven
percent of the cohort had oral cavity cancer.
Clinical evaluation at 2 months after (C-)RT revealed
that 74% of patients were clinically in complete remission. Of those, 5% of
patients had persistent disease suspected by MRI at 3 months and proved by
pathology.
Twenty-two percent of patients were clinically suspicious
for residual tumor at 2 months' clinical evaluation after (C-)RT. MRI found that
57% of these had suspicious/uncertain changes, and 46% of MRI suspicious
changes lead to a positive biopsy. Of patients clinically suspicious for
residual tumor, 22% had pathologically confirmed disease.
Four percent of the cohort did not undergo clinical evaluation
nor MRI (e.g. died or discontinued (C-)RT).
In total there
were 5%, 3%, and 0.4% of the total cohort with treatment failure at the nodal
site (N), primary tumor (T), or both T and N, respectively, proved by pathology
after a suspicious MRI evaluation. The 1 year follow up of those patients
revealed that, for N failures 64% were disease free at 1 year after salvage
treatment. While 9 %, 18%, and 9% of patients with N site failure died from the
disease, died from other causes/other cancer or had a recurrence within 1 year
of residual tumor diagnosis respectively.
Eighty-nine percent of patients with failure at T site died from the
disease within 1 year of diagnosis of the treatment failure.