1432P - Second primary malignances (SPMs) in patients (p) with gastrointestinal stromal tumors (GISTs) - a coincidence or an effect of imatinib?

Date 29 September 2014
Event ESMO 2014
Session Poster Display session
Topics Anti-Cancer Agents & Biologic Therapy
GIST
Presenter Anna Estival
Citation Annals of Oncology (2014) 25 (suppl_4): iv494-iv510. 10.1093/annonc/mdu354
Authors A. Estival1, O. Etxaniz1, J.L. Cuadra Urteaga2, M. Romeo3, I. Blanco4, M. Gil5, S. Ahlal6, I. Ojanguren4, A. Indacochea7, L. Vila5, C. Balana5
  • 1Medical Oncology, Catalan Institute of Oncology ICO Badalona Hospital Germans Trias i Pujol, Medical Oncology, 08916 - Badalona/ES
  • 2Medical Oncology Service, Catalan Institute of Oncology, Hospital Germans Trias i Pujol, 08916 - Badalona/ES
  • 3Medical Oncology, Institut Català d'Oncologia- Badalona, 08916 - Badalona/ES
  • 4Medical Oncology, hospital germans Trias i PUjol, badalona/ES
  • 5Medical Oncology, Catalan Institute of Oncology, Hospital Germans Trias i Pujol, 08916 - Badalona/ES
  • 6Medical Oncology, Institut Català d'Oncologia-Badalona, 08916 - Badalona/ES
  • 7Medical Oncology Department, Catalan Institute of Oncology ICO Badalona Hospital Germans Trias i Pujol, Medical Oncology, 08916 - Badalona/ES

Abstract

Aim

GISTs are the most common mesenchymal tumors of the gastrointestinal tract. Imatinib has become the standard treatment for unresectable metastatic GISTs and as adjuvant treatment in high-risk p. A high rate of SPMs (4.5 -33.3%) has been reported in p with sporadic GISTs and a potential association between imatinib treatment and the development of SPMs has been postulated.

Methods

We have retrospectively reviewed the incidence of SPMs in all p diagnosed with GIST and treated at a single institution between 1997 and 2012.

Results

A total of 95 p were diagnosed with GIST, 21 (22%) of whom developed SPMs. In addition, 18 of the 95 p (18.9%) had premalignant lesions, the most common of which were tubular adenoma (5 p) and melanocytic nevus (4 p). For the 21 p with SPMs, median age at GIST diagnosis was 45.6 years (range, 27-75). The GIST was located in the stomach in 10 p (47.6%) and in the small bowel in 11 (52.4%). The SPMs were in colon (6 p), breast (4 p), kidney (4 p), bladder (3 p), head and neck cancer (3 p), esophagus (2 p), lymphoproliferative disease (2 p), adrenal gland (2 p), skin cancer (1 p), prostate (1 p), pancreas (1 p), bone and soft tissue sarcoma (1 p), pheochromocytoma (1 p), and oligodendroglioma (1 p). 7p had more than one SPM. Only 1 p had been diagnosed with neurofibromatosis as a genetic syndrome. The SPMs were metachronous in 17 p (81%). Only 4 p (19.4%) received imatinib, 2 of whom developed SPMs after treatment.

Conclusions

We have observed SPMs in 22% and premalignant lesions in 18.9% of p with GISTs. While the cause of this high rate of SPMs is difficult to determine, it seems that factors other than imatinib treatment may play a role. Further investigation is warranted.

Disclosure

All authors have declared no conflicts of interest.