KRAS mutations have been detected in approximately 30% of all human tumors, and have been shown to predict response to some targeted therapies. The most common KRAS mutation-detection strategy consists of conventional PCR and direct sequencing. This approach has a 10-20% detection sensitivity depending on whether pyrosequencing or Sanger sequencing is used. To improve detection sensitivity, we compared our conventional method with the recently described co-amplification-at-lower denaturation-temperature PCR (COLD-PCR) method, which selectively amplifies minority alleles. In COLD-PCR, the critical denaturation temperature is lowered to 801C (vs 941C in conventional PCR). The sensitivity of COLD-PCR was determined by assessing serial dilutions. Fifty clinical samples were used, including 20 fresh bone-marrow aspirate specimens and the formalin-fixed paraffin-embedded (FFPE) tissue of 30 solid tumors. Implementation of COLD-PCR was straightforward and required no additional cost for reagents or instruments. The method was specific and reproducible. COLD-PCR successfully detected mutations in all samples that were positive by conventional PCR, and enhanced the mutant-to-wild-type ratio by 44.74-fold, increasing the mutation detection sensitivity to 1.5%. The enhancement of mutation detection by COLD-PCR inversely correlated with the tumor-cell percentage in a sample. In conclusion, we validated the utility and superior sensitivity of COLD-PCR for detecting KRAS mutations in a variety of hematopoietic and solid tumors using either fresh or fixed, paraffinembedded tissue.

Hepatic epithelioid hemangioendothelioma (HEH) is extremely rare, occurring in 1 to 2 per 100,000, with chemotherapy options not well defined. Our case involved a 49-year-old female who had hepatic masses and metastasis to the lungs with a liver biopsy revealing HEH. After developing a rash from sorafenib, thalidomide was started with the progression of disease stabilized. Resection is only an option in 10% of the cases; therefore, chemotherapy is the only line of treatment. Newer chemotherapy alternatives are targeting angiogenesis via the vascular endothelial growth factor. Thalidomide was first used as an antiemetic, but, sadly, soon linked to phocomelia birth defects. Given the mechanism of action against angiogenesis, thalidomide has a valid role in vascular tumors. In conclusion, the use of thalidomide as chemotherapy is novel and promising, especially in the setting of a rare vascular liver tumor such as HEH.

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