Waldeyer's Ring Marginal Zone B-Cell Lymphoma: Which Is Their Clinical and Prognostic Feature, Nodal or Extranodal?

Waldeyer's ring (WR) is circular band of lymphoid tissue located at the opening of the respiratory and digestive tract. There is controversy as to whether WR should be considered as a nodal or extranodal site. In this study, we conducted retrospective analyses of WR involving MZLs (WR-MZLs) to identify their clinical features, treatment, prognosis- favor nodal or extranodal. And we want to get additional information about specific organ relationship between WR-MZL and other MALT sites.

From 1987 to 2010, 124 patients who were histologically confirmed as a MZL arising from head and neck (H&N) area was including WR (47 patients) were reviewed. Primary orbit and ocular adnexa MZL patient was excluded this data collection.

The male/female ratio of the 47 patients was 23 to 24. The median age was 53 years (range, 17–77). The commonly involving sites were tonsil (53.2%) followed by nasopharyn (40.4%). Fourteen patients (29.7%) were accompanied with extra-WR area MALT site- gastrointestinal tract (14.9%), ocular and adnexa (12.8%). Ann Arbor stage I/II disease was present in 50% (23 out of 46). Thirty-nine patients were categorized into the low/low-intermediate risk group (84.8%) according to International Prognostic Index (IPI). Complete and partial remissions were achieved in 18 (78.3%) and 2 (8.7%) of the 23 stage I/II patients. In 23 patients with stage III/IV, CR and PR were achieved in 15 (65.2%) and 4 (17.4%), respectively. The median progression-free survival (PFS) was 3.6 years (95% CI, 2.4–4.8 years). The estimated 5-year overall survival (OS) was 88%. Compared with H&N MALT site MZLs, WR-MZLs were significantly poor in PFS and OS (P=0.005 and P=0.007).

WR-MZLs were also an indolent disease like general MZL. But, WR-MZL patients presented with more advanced stage and poorer survivals than other site H&N MZL patients. Therefore, even though WR has been considered histologically extranodal MALT organ, clinically it is closer to nodal MZL.

No relevant conflicts of interest to declare.