Fig. 2.17. Sinonasal NK/T lymphoma. a Angiocentric infiltrate of atypical lymphocytes with extensive necrotic areas. b Strongly positive CD56 immunoreaction v . r.
Fig. 2.17. Sinonasal NK/T lymphoma. a Angiocentric infiltrate of atypical lymphocytes with extensive necrotic areas. b Strongly positive CD56 immunoreaction inflammatory cells. Pseudoepitheliomatous hyperplasia of the covering epithelium may occur . NK/T cell lymphoma is almost always associated with EBV posi-tivity. The most typical immunophenotypes are CD2+, CD56+ (Fig. 2.17b), surface CD3-, and cytoplasmic CD3epsilon+. Most cases are also positive for cytotoxic granule-associated proteins (granzyme B, TIA-1 and perforin). They are usually negative for other T and NK-cell associated markers. Sinonasal lymphomas demonstrating CD3epsilon+, CD56-, cytotoxic molecule+, and EBV+ are also included within the NK/T category. The commonest cytogenetic abnormality found in NK/T-cell lymphoma is the 6q-22-23 deletion . The prognosis of nasal NK/T-cell lymphoma is variable. Some patients respond well to therapy and others die of disease despite aggressive therapy .
Sinonasal malignant lymphomas of either B-cell or T-cell derivation need a careful differential diagnosis with other small round cell tumours (Table 2.2) and with ex-tramedullary plasmacytoma [6, 46], as well as with ex-tramedullary tumours composed of myeloid or lymphoid blasts .
Plasmacytoma of the sinonasal tract appears as a diffuse infiltration of mature plasma cells of the mucosa; occasionally, tumour cells are less differentiated, and diagnosis may be difficult on a histologic basis [2, 6, 46, 185]. Immunohistochemical staining for CD138 and k and X chains may be helpful. Full examination of the patient is required to exclude disseminated disease.
Was this article helpful?
Moles, warts, and other unsightly irregularities of the skin can be bothersome and even embarrassing. They can be removed naturally... Removing Warts and Moles Naturally! If you have moles, warts, and other skin irregularities that you cannot cover up affecting the way you look, you can have them removed. Doctors can be extremely expensive. Learn the natural ways you can remove these irregularities in the comfort of your own home.