Dataset Information

Rare Incidence of ROS1 Rearrangement in Cholangiocarcinoma.

ABSTRACT:

Purpose

The recent discovery and characterization of an oncogenic ROS1 gene rearrangement has raised significant interest because small molecule inhibitors are effective in these tumors. The aim of this study was to determine frequency and clinicopathological features associated with ROS1 rearrangement in patients with cholangiocarcinoma (CCA).

Materials and methods

A total of 261 patients who underwent surgery for CCA between October 1997 and August 2013 were identified from an international, multi-institutional database. ROS1 rearrangement was evaluated by break-apart fluorescence in situ hybridization using tissue microarrays of these patients.

Results

Of 261 CCA evaluated, three cases (1.1%) showed ROS1 rearrangement by fluorescence in situ hybridization (FISH), all of which were derived from intrahepatic origin. ROS1 protein expression was observed in 38 samples (19.1%). Significantly larger tumor size was observed in ROS1 immunohistochemistry (IHC)-negative patients compared with ROS1 IHC-positive patients. ROS1 FISH-positive patients had a single tumor with a median size of 4 cm and well-to-moderate differentiation. Overall, there was no difference in terms of baseline characteristics, overall survival, and recurrence-free survival between ROS1-positive and -negative patients.

Conclusion

ROS1 rearrangement was detected in 1.1% of CCA patients. Although rare, conduct of clinical trials using ROS1 inhibitors in these genetically unique patients is warranted.

SUBMITTER: Lim SM

PROVIDER: S-EPMC5266400 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Publications

Rare Incidence of <i>ROS1</i> Rearrangement in Cholangiocarcinoma.

Lim Sun Min SM Yoo Jeong Eun JE Lim Kiat Hon KH Meng Tai David Wai DW Cho Byoung Chul BC Park Young Nyun YN

Cancer research and treatment 20160427 1

<h4>Purpose</h4>The recent discovery and characterization of an oncogenic <i>ROS1</i> gene rearrangement has raised significant interest because small molecule inhibitors are effective in these tumors. The aim of this study was to determine frequency and clinicopathological features associated with <i>ROS1</i> rearrangement in patients with cholangiocarcinoma (CCA).<h4>Materials and methods</h4>A total of 261 patients who underwent surgery for CCA between October 1997 and August 2013 were identi ...[more]

PMID: 27121721

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