Imatinib as adjuvant therapy for high risk GIST: a case report

We here report a case of 42 years old man who experienced sudden abdominal cramps and then underwent explorative laparotomy because of the CT-finding of a 23 cm abdominal mass at the stomach. Frozen specimen analysis indicated a probable gastrointestinal stromal tumor (GIST). Radical excision was performed. Definitive pathological analysis revealed a CD34 and CD 117(c-KIT) positive GIST with a mitotic count of 15/50 HPF. These features indicate a disease with an high risk of recurrence within few years. Molecular analysis found a WK557-558 deletion of c-KIT exon 11, that indicates a poor prognosis in patients with completely resected GIST. In april 2010 he started adjuvant therapy with imatinib at standard dose of 400 mg/day that was well tolerated: he reported only G1 periocular edema and conjunctivitis. Considering the risk of disease recurrence he continued adjuvant therapy beyond the first year

Different quality of treatment in retroperitoneal sarcomas (RPS) according to hospital-case volume and surgeon-case volume: a retrospective regional analysis in Italy

Abstract Background Retroperitoneal sarcomas (RPS) should be surgically managed in specialized sarcoma centers. However, it is not clearly demonstrated if clinical outcome is more influenced by Center Case Volume (CCV) or by Surgeon Case Volume (SCV). The aim of this study is to retrospectively explore the relationship between CCV and SCV and the quality of surgery in a wide region of Northern Italy. Methods We retrospectively collected data about patients M0 surgically treated for RPSs in 22 different hospitals from 2006 to 2011, dividing them in two hospital groups according to sarcoma clinical activity volume (HCV, high case volume or LCV, low case volume hospitals). The HCV group (> 100 sarcomas observed per year) included a Comprehensive Cancer Center (HVCCC) with a high sarcoma SCV (> 20 cases/year), and a Tertiary Academic Hospital (HVTCA) with multiple surgeon teams and a low sarcoma SCV (≤ 5 cases/year for each involved surgeon). All other hospitals were included in the LCV group (< 100 sarcomas observed per year). Results Data regarding 138 patients were collected. Patients coming from LCV hospitals (66) were excluded from the analysis as prognostic data were frequently not available. Among the 72 remaining cases of HCV hospitals 60% of cases had R0/R1 margins, with a more favorable distribution of R0/R1 versus R2 in HVCCC compared to HVTCA. Conclusions In HCV hospitals, sarcoma SCV may significantly influence RPS treatment quality. In low-volume centers surgical reports can often miss important prognostic issues and surgical quality is generally poor

Clonal evolution and resistance to EGFR blockade in the blood of colorectal cancer patients

Colorectal cancers (CRCs) evolve by a reiterative process of genetic diversification and clonal evolution. The molecular profile of CRC is routinely assessed in surgical or bioptic samples. Genotyping of CRC tissue has inherent limitations; a tissue sample represents a single snapshot in time, and it is subjected to spatial selection bias owing to tumor heterogeneity. Repeated tissue samples are difficult to obtain and cannot be used for dynamic monitoring of disease progression and response to therapy. We exploited circulating tumor DNA (ctDNA) to genotype colorectal tumors and track clonal evolution during treatment with the epidermal growth factor receptor (EGFR)-specific antibodies cetuximab or panitumumab. We identified alterations in ctDNA of patients with primary or acquired resistance to EGFR blockade in the following genes: KRAS, NRAS, MET, ERBB2, FLT3, EGFR and MAP2K1. Mutated KRAS clones, which emerge in blood during EGFR blockade, decline upon withdrawal of EGFR-specific antibodies, indicating that clonal evolution continues beyond clinical progression. Pharmacogenomic analysis of CRC cells that had acquired resistance to cetuximab reveals that upon antibody withdrawal KRAS clones decay, whereas the population regains drug sensitivity. ctDNA profiles of individuals who benefit from multiple challenges with anti-EGFR antibodies exhibit pulsatile levels of mutant KRAS. These results indicate that the CRC genome adapts dynamically to intermittent drug schedules and provide a molecular explanation for the efficacy of rechallenge therapies based on EGFR blockade