Clinical findings of extranodal SNT lymphoid malignancies in a four-decade single-centre series.

Sinonasally located lymphoid malignancies are rare lesions with first symptoms similar to other obstructive conditions. Additionally, they often coexist with nasal inflammation and mucosal necrosis. Therefore, time from the first symptoms to diagnosis tends to be long. Awareness and early diagnosis of this disease entity could improve treatment outcome. Altogether, 142 patients with sinonasal or nasopharyngeal (i.e. sinonasal tract, SNT) lymphoid malignancies, diagnosed and treated at the Helsinki University Hospital, during a 39-year period from 1975 to 2013, were retrospectively reviewed. There were 90 males (63 %) and 52 females (37 %) with a median age of 64 years (range 26-92). Eighty-four percent of the patients had primary diseases and 16 % had relapses of lymphoid malignancies primarily diagnosed at other locations. The mean duration of symptoms prior to diagnosis was 4.8 months (range 0.5-24). The most common histological entity was diffuse large B-cell lymphoma (43 %), followed by plasmacytoma (18 %). The most common location was nasopharynx (58 %) followed by nasal cavity (44 %) and paranasal sinuses (35 %). Sixty-nine percent of the lesions were at a single anatomic location of the sinonasal tract. Fifty-two percent of the cases were of Ann Arbor Stage I. Lymphoid malignancies form an important and diverse group in the differential diagnosis of SNT tumours. They most often present with general obstructive nasal symptoms due to tumour location. Most of them are primary lesions, highlighting the importance of an accurate diagnosis as early as possible.