E. DEMIRALAY ET AL.
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tochemistry proces. Based on this pattern of reactivity we
concluded that our tumor has distinctive character.
Others suggested embryologic hypothesis as mullerian
displacement in the kidney [13]. Another hypothesis to
be considered is that of an epithelial-stromal interaction
in a status of hormonal hyperstimulation [11]. Estrogen
seems to be important, but its role may be to promote
rather than initiate oncogenesis [14]. A case with trans-
location t (1;19) has recently been described [5].
By electron microscopy, it has been shown that some
tubules within the tumor had features of the proximal
tubular epithelium, while other tubules had features of
the thin segment of the loop of Henle, suggesting that the
tubules are entrapped rather than neoplastic [6].
Malign transformation, recurrence, and metastasis are
rare; however, a few cases of malignant MESTK have
been reported in the literature recently [2,4,5,10]. Al-
though malignancy of the epithelial component in these
tumors has not yet been documented, some authors re-
ported stromal malignancy [2,15,16].
MESTK have excellent prognosis and should be dif-
ferentiated especially from renal cell carcinoma. These
tumors do not hold diagnostic characteristics due to that
fact the tumors clinically and radiologically can not be
distinguished.
In conclusion, to distinguish non-diagnostic tumors;
radiological research could be the most appropriate solu-
tion. We hope the suggested area will provide solid re-
sults for the non-diagnostic cases.
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