[1149] Amplification and Overexpression of HER-2/neu in Salivary Duct Carcinoma and Salivary Duct Carcinoma Ex Pleomorphic Adenoma of the Salivary Gland

M Urano, Y Kiriyama, Y Takakuwa, Y Mizoguchi, M Kuroda. Fujita Health University, School of Medicine, Toyoake, Aichi, Japan

Background: Salivary duct carcinoma (SDC) is an aggressive malignant tumor associated with high mortality. Recently, the indications for use of trastuzumab (Herceptin) as adjuvant therapy for SDC, similar to breast cancer, has been discussed. The object of this study is to clarify the relationship between HER-2/neu protein overexpression in immunohistochemistry (IHC) and gene amplification detected by fluorescence in situ hybridization (FISH) in SDC.
Design: We studied five cases of pure SDC and nine cases of SDC ex pleomorphic adenoma (PA) (13 male and 1 female, age 37 to 85, Ave. 62 yr) diagnosed between 1997 and 2007. Formalin-fixed, paraffin-embedded tissue from 14 cases were evaluated by IHC and FISH for HER-2/neu status.
Results: Of the 6 cases (43%) scored 3+ by IHC and all of them showed gene amplification by FISH. 4 cases (29%) scored 2+ and half of them showed amplification. 3 cases (21%) scored 1+ and 1 case (7%) scored 0 showed no amplification. 8 of 10 cases (80%) scored more than 2+ by IHC showed HER-2/neu gene amplification consequently.

table 1
casehistologyAgeGenderOutcomeHER2-IHCHER2-FISH
1SDC66MDead3+Amplified
2SDC85MDead0Not Amplified
3SDC60MDead3+Amplified
4SDC62MDead3+Amplified
5SDC78MDead2+Not Amplified
6SDC ex PA37MAlive2+Amplified
7SDC ex PA77MAlive1+Not Amplified
8SDC ex PA72MDead1+Not Amplified
9SDC ex PA55MAlive2+Not Amplified
10SDC ex PA70MDead1+Not Amplified
11SDC ex PA55MDead2+Amplified
12SDC ex PA41FAlive3+Amplified
13SDC ex PA66MAlive3+Amplified
14SDC ex PA50MAlive3+Amplified



Conclusions: Clinically, most patients with SDC are in advanced stage and are metastasized when they visit clinics, and it is difficult to perform curable surgical treatment on them and some are inoperable. Our data demonstrate that Trastuzumab has a possibility of adjuvant therapy on the patients with FISH-positive HER-2/neu SDC and may play a role for improvement of their prognosis.
Category: Head & Neck

Monday, March 9, 2009 1:00 PM

Poster Session II # 154, Monday Afternoon

 

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