Primary extranodal lymphoma: response to treatment and factors influencing prognosis.

The cumulative 10 year lymphoma experience of a teaching hospital and two of its affiliated institutions was reviewed. From this group, a series of 39 cases of regionally localized primary extranodal lymphomas (Ann Arbor Stages IE and IIE) were selected for study. This group of patients was analyzed for response to initial curative treatment and factors influencing prognosis. The disease-free survival rate following initial treatment is 41% and the rate is 51% if those treated for a single relapse are included. Factors which clearly influence prognosis in this group are stage (extent of disease) at presentation and Rappaport histologic subclassification. The relationships of anatomic site and age to prognosis independent of other factors are unclear. There appears to be an association between sites of involvement in Waldeyer's Ring and the gastrointestinal tract seen both initially and in sites of relapse. An analysis of relapse patterns revealed that 33% of relapses occur as solitary extranodal "skip" recurrences that when treated with radical local treatment may result in long disease-free survival. The latter is one of several findings which suggest that a modification of the current Ann Arbor staging system may be necessary to encompass certain unique features of this group of tumors.