The positive impact of cytological specimens for EGFR mutation testing in non-small cell lung cancer: a single South East Asian laboratory's analysis of 670 cases.

OBJECTIVES: To compare the rejection rates of non-small cell lung cancer (NSCLC) samples obtained by differing sampling methods for testing by Sanger sequencing for epidermal growth factor receptor (EGFR) mutations. To assess the association between unsatisfactory outcomes and the quantity of DNA extracted from cytological versus histological samples. METHODS: Six hundred and seventy NSCLC samples referred to our centre from 2008 to 2010 were reviewed as a consequence of sample rejection, presence of EGFR mutations, cytological versus histological sampling methods, DNA quantity and the unsatisfactory genotyping rate. RESULTS: Eighty samples were rejected for testing in similar proportions of histological and cytological samples (11.9% versus 10.9%) usually (n = 75) because the amount of cellular material was judged insufficient in small biopsies or cytology samples. The remaining 590 samples on which EGFR testing was attempted yielded 51 (8.6%) unsatisfactory test outcomes caused by failure of the polymerase chain reaction (PCR) (n = 47 cases), uninterpretable Sanger chromatograms (n = 3 cases) and insufficient DNA extracted for PCR (n = 1 case). The difference in rates of unsatisfactory outcomes between cytological samples (seven of 147 samples or 4.7%) versus tissue samples (44 of 443 samples or 9.9%) was clinically relevant but not statistically significant (Mann-Whitney test; P < 0.081). There was no association between the concentration of DNA extracted and the likelihood of an unsatisfactory analysis; which was similar in all types of sections (large and small) while 0% of 37 cytology slides were unsatisfactory. CONCLUSIONS: Utilizing cytology samples for EGFR testing avoids unnecessary patient re-biopsing and yields a clinically superior satisfactory rate to the overall satisfactory rate of tissue biopsies of NSCLC. The quality rather than quantity of DNA extracted may be a more important determinant of a satisfactory result.

KRAS and BRAF mutation analysis can be reliably performed on aspirated cytological specimens of metastatic colorectal carcinoma.

BACKGROUND: Sanger sequencing is one of several reliable methods in use to detect KRAS and BRAF mutations to facilitate clinical patient selection for anti-epidermal growth factor receptor (EGFR) monoclonal antibody therapy in unresectable metastatic colorectal adenocarcinoma (CRC). Most analyses are made on pretreatment biopsy or resection specimens. There is a scarcity of published studies on the suitability of cytological samples for KRAS testing in this setting. METHODS: DNA extraction was attempted on 11 search-retrieved paired cases of histological resections or excisions of CRC and their corresponding cytological samples (representing metastases) and tested for KRAS mutations in exon 2 and 3, as well as BRAF exon 15 mutations by Sanger sequencing. Only KRAS wild-type cases were subjected to BRAF analysis because this is the setting with true diagnostic value, as these mutations are mutually exclusive. RESULTS: Of the 11 paired cases analysed, only eight histology cases showed satisfactory DNA quality for sequencing. Thus, only eight of the corresponding cytology cases were analysed. Seven of the eight cases tested showed the same KRAS genotype on both the aspirated cytology specimen of metastatic carcinoma and the primary tumour (histological specimen), from which we derive an overall concordance rate of 87.5%. The single discordant case was likely to be a true difference as it was demonstrated again on repeat testing of both samples. No BRAF mutations were detected on the four KRAS wild-type cases. CONCLUSION: A range of cytological samples are suitable for KRAS and BRAF mutation testing, be it from previously stained preparations or cell blocks. These samples would be highly valuable in cases where cytological samples are the only material available for mutation testing.

The use of Imagent BP as a blood pool contrast agent to visualize and quantitate liver tumor burden.

The accurate quantitation of liver tumor burden and visualization of lesions in three dimensions (3D) can assist in treatment planning and can allow monitoring of therapy. Previous attempts have used CT and standard contrast media. Because the iodinated agents rapidly diffuse into tumors, usually effacing, and at time enhancing tumor edges, they decrease accuracy and make image segmentation difficult. CT portography suffers from flow related artifacts and does not allow the distinction of tumors from hemangiomas. Blood pool contrast is ideal in this setting since it enhances liver, liver vessels and hemangiomas, but not tumors, 'physiologically' splitting the image into normal and abnormal tissues. This ongoing study assesses the feasibility of this technique to visualize tumor and presents a scheme to automatically quantitate tumor volume. It utilized a rabbit VX2 liver tumor model and CT scanning shortly after the infusion of 3 ml/kg perflubron emulsion. Cut sections of the frozen carcass served as gross pathologic correlation. Images were imported onto a Sparc workstation, 3D reformatted and tumor and liver volume calculated. Histograms of pixel intensity clearly separated tumors from liver and liver from surrounding structures allowing the easy demarcation of tumor and liver margins.

Post-menopausal smear patterns--a review of vaginal smears in 480 women.

Cytohormonal evaluation was done on the vaginal smears of 480 normal, asymptomatic, post-menopausal women whose ages ranged from 36 to 74 years. About 50% showed atrophic smears consistent with total oestrogen lack. 41% had mild to moderately proliferative smears compatible with sub-optimal oestrogen stimulus. 9% showed a highly proliferative pattern typical of unopposed oestrogen effect and in this group two women had atypical endometrial cells in their smears, which subsequently were found to come from an atypical endometrial hyperplasia and an endometrial adenocarcinoma-in-situ. The clinical relevance of cytohormonal studies in post-menopausal women is briefly discussed.