Characterizing gastrointestinal stromal tumors and evaluating neoadjuvant imatinib by sequencing of endoscopic ultrasound-biopsies

Figure 1 Flow charts of the study inclusion process, February 2006-December 2015. A: The Baseline Period, observational study design (2006-2011); B: The Study Period, interventional study design (2012-2015). GIST: Gastrointestinal stromal tumor; EUS: Endoscopic ultrasound; FNA: Fine-needle aspiration; FNB: Fine-needle biopsy.

Figure 2 The diagnostic sensitivity of endoscopic ultrasound-guided sampling in unique Gastrointestinal stromal tumor-cases (n_tot = 64) examined at the Sahlgrenska University Hospital from 2006 to 2015. The error bars represent the 95%CI. FNA: Fine-needle aspiration; FNB: Fine-needle biopsy; TCB: Trucut-biopsy; GIST: Gastrointestinal stromal tumor; EUS: Endoscopic ultrasound.

Figure 3 The Ki-67-index (%) of the fine-needle biopsy and of the corresponding resected specimen in each patient who underwent resection. A: Patients not treated with neoadjuvant imatinib; B: Patients treated with neoadjuvant imatinib who carried an imatinib-sensitizing KIT- or PDGFRA-mutation; C: Patients treated with neoadjuvant imatinib who carried a KIT- or PDGFRA-mutation (or wild type profile), which indicates resistance to imatinib.

Figure 4 Ki-67-immunostaining of gastrointestinal stromal tumors-tumor tissue in three endoscopic ultrasound-biopsies and in the three corresponding resected specimens. Digital photos (magnification × 40): EUS-biopsy-tissue (left) and resected specimen tissue (right). Cell nuclei (brown color) are positive for Ki-67 while other cell nuclei (blue color) are negative for Ki-67. Scale bar equals 50 μm. A and B: Case #18, Neo- group (KIT exon 11 D579del, Ki-67_EUS: 6.6%, Ki-67_SURG: 6.3%); C and D: Case #22, Neo + s group (KIT exon 11 V559D, Ki-67_EUS: 5.6%, Ki-67_SURG 0.3%); E and F: Case #26, Neo + r group (PDGFRA exon 18 p.D842V, Ki-67_EUS: 2.7%, Ki-67_SURG 2.5%). EUS: Endoscopic ultrasound.