Controversies Surrounding the BMD Reporting Standard for the Determination of 10-Year Absolute Fracture Risk: A Canadian Perspective.

The Canadian Association of Radiologists and Osteoporosis Canada currently endorse a fracture risk prediction tool called CAROC. It has been used in Canada since 2005 with an update in 2010. It is an integral part of bone mineral densitometry reporting across the country.

Junctioning longitudinally adjacent PTVs with Helical TomoTherapy.

Irradiation of longitudinally adjacent PTVs with Helical TomoTherapy (HT) may be clinically necessary, for example in treating a recurrent PTV adjacent to a previously-treated volume. In this work, the parameters which influence the cumulative dose distribution resulting from treating longitudinally adjacent PTVs are examined, including field width, pitch, and PTV location. In-phantom dose distributions were calculated for various on- and off-axis cylindrical PTVs and were verified by ion chamber and film measurement.

Evaluation of cisplatin treatment given concurrently with pulsed irradiation in cisplatin sensitive and resistant human ovarian carcinoma cell lines.

The aim was to investigate the effect of combined treatment of cisplatin with acute or pulsed radiation in human ovarian carcinoma cells sensitive and resistant to cisplatin. Human ovarian cancer cell parental line A2780s and a derivative cisplatin-resistant line A2780cp were given cisplatin treatment before a single acute dose irradiation or concurrently during a pulsed-dose irradiation sequence. Cells were irradiated in the confluent state, trypsinized and plated after treatment.

TCP isoeffect analysis using a heterogeneous distribution of radiosensitivity.

A formula for the alpha/beta ratio is derived using the heterogeneous (population averaged) tumor control model. This formula is nearly identical to the formula obtained using the homogeneous (individual) tumor control model, but the new formula includes extra terms showing that the alpha/beta ratio, the ratio of the mean value of a divided by the mean value of beta that would be observed in a patient population, explicitly depends on the survival level and heterogeneity. The magnitude of this correction is estimated for prostate cancer, and this appears to raise the mean value of the ratio estimate by about 20%.