Completing a genomic characterisation of microscopic tumour samples with copy number

BACKGROUND

Genomic insights in settings where tumour sample sizes are limited to just hundreds or even tens of cells hold great clinical potential, but also present significant technical challenges. We previously developed the DigiPico sequencing platform to accurately identify somatic mutations from such samples.

RESULTS

Here, we complete this genomic characterisation with copy number. We present a novel protocol, PicoCNV, to call allele-specific somatic copy number alterations from picogram quantities of tumour DNA. We find that PicoCNV provides exactly accurate copy number in 84% of the genome for even the smallest samples, and demonstrate its clinical potential in maintenance therapy.

CONCLUSIONS

PicoCNV complements our existing platform, allowing for accurate and comprehensive genomic characterisations of cancers in settings where only microscopic samples are available.

Incidence of bony secondary at presentation of breast carcinoma in our region

Study is conducted to evaluate the incidence of bony secondary and to evaluate the need for routine bone scintigraphy at the time of presentation of breast carcinoma in this region. Of the total 130 patients evaluated by bone scan, sixty (n = 60, 46.15%) had secondary lesion in bone. Among the 54 preoperative patients, all with positive FNAC, twenty (n = 20, 37.03%) had bony metastases. Of the 76 post-operative patients, forty (n = 40, 52.63%) had secondary bone lesions. Single lesion was seen in only five (n = 5, 8.53%) cases. Rest fifty five (n = 55, 91.67%) had multiple bony secondaries. Most of the postoperative cases (n = 40, 52.63%) were invasive/infiltrative duct cell carcinoma. The very high incidence of bony secondary appears to be due to delayed presentation associated with poor socioeconomic condition, ignorance and also shyness. Bony metastases at the time of presentation suggests poor prognosis. As it can affect therapeutic management of these patients, routine bone scintigraphy at the time of presentation of breast carcinoma patients to a tertiary label hospital is proposed, against conflicting conclusion by papers in the developed countries.