The utilization of multidisciplinary tumor boards (MDT) in clinical routine: results of a health care research study focusing on patients with metastasized colorectal cancer.

PURPOSE: Multidisciplinary tumor boards (MDT) have been advocated as standard of care in modern oncology. German guidelines for metastasized colorectal cancer (mCRC) recommend MDT discussion of colon cancer patients after completion of primary tumor therapy but stage IV colon cancer as well as rectal cancer patients prior to any therapy. In this health care research study, we evaluated application and decisional consequences of this approach in clinical routine. METHODS: All major institutions providing oncological care in southern Lower Saxony and Northern Hesse (N = 11) were invited. Patients with mCRC diagnosed between 01/2011 and 12/2013 were eligible. Data were collected using a standardized patient report form and stored in a GCP-conform EDC-system (secuTrial®). RESULTS: A university medical center, four teaching hospitals, one communal hospital, and three oncological focus practices participated in the study. In total, 470 patients with a median age of 70 years were enrolled. Guideline conform MDT discussion was performed in 63% of operated colon cancer patients, 38% of stage IV colon cancer patients and 47% of rectal cancer patients, respectively. Resection of metastases was performed in 41% of cases. Patients ≥70 years (n = 250) received significantly more often treatment following MDT discussion (86 versus 64%, p = 0.0002). Not the resection rate (48 versus 57%, p = 0.1574) but indication for preoperative chemotherapy (57 versus 33%, p = 0.0056) significantly differed when patients with single organ metastases experienced MDT discussion. CONCLUSIONS: MDT discussion is not as established as advocated by national guidelines. Treatment decisions differ especially in older patients and those with single organ metastases.

Molecular cytogenetic monitoring from CD34+ peripheral blood cells in myelodysplastic syndromes: first results from a prospective multicenter German diagnostic study.

The gold standard of cytogenetic analysis in myelodysplastic syndromes (MDS) is conventional chromosome banding (CCB) analysis of bone marrow (BM) metaphases. Most aberrations can also be detected by fluorescence-in situ-hybridization (FISH). For this prospective multicenter German diagnostic study (www.clinicaltrials.gov: #NCT01355913) 360 patients, as yet, were followed up to 3 years by sequential FISH analyses of immunomagnetically enriched CD34+ peripheral blood (PB) cells using comprehensive FISH probe panels, resulting in a total number of 19,516 FISH analyses. We demonstrate that CD34+ PB FISH correlates significantly with CCB analysis and represents a feasible method for a reliable non-invasive cytogenetic monitoring from PB.

Surgical management after neoadjuvant imatinib therapy in gastrointestinal stromal tumours (GISTs) with respect to imatinib resistance caused by secondary KIT mutations.

BACKGROUND: In metastasized GISTs, resistance to imatinib after initial tumour response has been associated with observation of secondary mutations in the activation loop of KIT. The aim of the current study was to evaluate the tumour response and observance of secondary KIT mutations in a case of GIST undergoing neoadjuvant imatinib therapy. METHODS: We report on a case of an initially unresectable gastric GIST with curative resection after 10 months of neoadjuvant imatinib therapy. Mutation analysis of KIT was performed on a pretherapeutic biopsy specimen, as well as on the resected tumour specimen. RESULTS: The pretherapeutic biopsy revealed cKit positive tumour cells with mutation of KIT exon 11 Del 560-576. The remaining tumour mass after neoadjuvant imatinib therapy almost exclusively consisted of hypocellular myxohyalinale stroma with rare microfoci of cKit positive tumour cells. Laser microdissection of several tumour microfoci revealed two additional point mutations located in the activation loop of KIT exon 17, C809G and N822Y, each observed separately in a distinct microfocus. Neither of these two point mutations has been reported in a GIST so far. CONCLUSIONS: Neoadjuvant imatinib therapy successfully reduces tumour size in GISTs. Since resistance relevant secondary mutations of the activation loop of KIT may be observed after neoadjuvant imatinib therapy, the time elapse with preoperative imatinib therapy should be chosen as short as curative tumour resection or function sparing surgery can be carried out. The determination of the optimal time point for surgery is therefore a critical event and will be discussed.