Features of signet ring cell lymphomas:
(1) The presence of signet ring cells.
(2) Cytokeratin markers are negative.
(3) Markers for other tumors with signet ring cells negative.
(4) Markers for lymphoid differentiation are positive.
Signet ring cell lymphomas may be:
(1) B cell (CD20, other)
(2) T cell
(3) myeloma
The diagnosis may not be a problem if
(1) there is involvement of the lymph nodes or spleen.
(2) there is evidence of progression to a higher grade of lymphoma
Diagnosis can be a problem if the lymphoma involves extranodal sites - skin, thyroid, tonsil, central nervous system, salivary gland, etc. It can be a real problem if it involves the stomach or large intestine.
