Περίληψη:
AIM: To investigate the incidence of KIT immunohostochemical staining in
(GI) stromal tumors (GISTs), and to analyze the clinical manifestations
of the tumors and prognostic indicators.
METHODS: We retrospectively analyzed 50 cases of previously diagnosed
GISTs. Tissue samples were assessed with KIT (CD117 antigen), CD34, SMA,
desmin, S-100, NSE, PCNA, Ki-67, and BCL-2 for immunohistochemical study
and pathological characteristics were analyzed for prognostic factors.
RESULTS: Fifteen tumors (30%) were negative in KIT staining. A
significant association was observed between gender (male patients:
14/15) and KIT-negative staining (P = 0.003). The patients’s mean age
was 56.6 years. Tumors developed in stomach (n = 8), small intestine (n
= 5), large intestine (n = 1) and oesophagus (n = 1). The mean tumor
size was 5.72 cm. The mitotic count ranged from 0-29/50 HPF (mean: 3.4)
and 73% of tumors showed no necrosis. The majority of the tumors (67%)
had dual or epithelioid differentiation. Tumors were classified as very
low or low risk (n = 7), intermediate risk (n = 5), and high risk (n =
3) groups. Twelve (80%) patients were alive without evidence of
residual tumor for an average period of 40.25 mo (12-82 mo); three
patients developed metastatic disease to the liver and eventually died
within 2-12 mo (median survival: 8.6 mo).
CONCLUSION: A small subgroup of GISTs fulfils the clinical and
morphological criteria of these tumors, and lacks KIT expression. These
tumors predominantly developed in the stomach, being dual or epithelioid
in morphology, which are classified as low risk tumors and presented a
better survival status than KIT-positive tumors. The ability to diagnose
GISTs still depends on immunohistochemical staining but the research
should extend in gene mutations. (c) 2007 The WJG Press. All rights
reserved.
Συγγραφείς:
Kontogianni-Katsarou, Katerina
Lariou, Constantina
Tsompanaki,
Eugenia
Vourlakou, Christina
Kairi-Vassilatou, Evi
Mastoris,
Costas
Pantazi, Georgia
Kondi-Pafiti, Agatha
