Aetiology : can complicate an established history of gluten-sensitive enteropathy (celiac disease
)
but most often occurs following a short history of celiac disease and/or
dermatitis herpetiformis (Jaffe ES, Railfkiaer E. Mature T-cell and NK
neoplasms: introduction. In: Jaffe ES, Harris NL, Stein H, Vardiman JW,
eds World Health Organization Classification of Tumours: Pathology and
Genetics of Tumours of Hematopoetic and lymphoid Tissues. IARC Press: Lyon;
2001:191–194). Even in the absence of a known history of celiac disease,
there is usually histologic evidence of villous atrophy and crypt hyperplasia
in the adjacent bowel when the tumor is excised. In the past several years
the understanding of celiac-associated lymphoma has improved. Isaacson
and Wrightref
have shown that celiac-associated lymphomas were of single histogenetic
type and probably derived from histiocytes. Subsequent immunohistochemical
and molecular studies indicated that these tumors are of T-cell originref1,
ref2.
Wright et alref
later described a patient with CD, jejunal ulcerations, and a clonal rearrangement
of the TCRg and TCRb
chain gene together with karytotype abnormalities of jejunal T cells. From
this case report, they hypothesized that adult-onset CD could be a low-grade
lymphoma of intraepithelial T lymphocytesref.
However, other studies performed on isolated gd
T-cell clonesref
or fresh biopsy materialref
from duodenojejunal mucosa of CD patients have found no evidence of the
expansion of one or more T-cell clones in CD. It may be suggested that
monoclonal T cells arose from a polyclonal infiltrate after long years
of untreated, asymptomatic CDref.23
Studies performed in human normal colon and jejunum have shown oligoclonality
of IEL bearing phenotyperef1,
ref2,
ref324-26
and TCR-bearing cellsref1,
ref2.27,28
It was thus not unexpected that some patients with uncomplicated CD and
controls had an oligoclonal pattern. However, in patients with complicated
CD, a dominant clone was evidenced, indicating a preferential expansion
of a T-cell clone among a highly cellular inflammatory mucosa
Symptoms & signs :
