However, it is only after 1400 that we can be certain that it was being used as a surname rather than as a description of someone's occupation or status. There was never a Highland clan of that name. However, it is frequently found among the Clan Chattan confederacy. Clarks appear to have been a sept (under the protection) of the MacPhersons (whose origins were also from the church, Mac-a Phearsain meaning in Gaelic son of the parson in the days when celibacy of the priesthood was not enforced).
Prostate cancer is frequently seen as an area of low signal abnormality in the peripheral zone. Some cancers are isointense and cannot be seen on standard MRI. Other conditions, such as prostatitis, atrophy and calcifications, may also cause low signal intensity and result in a number of false positives.
1 15% of men with prostate cancer have a normal PSA. 2  There is no conclusive evidence that detection of early prostate cancer leads to longer survival. 3  The test cannot distinguish between aggressive and slow-growing cancers and may detect tumours that would not otherwise become evident in the patient's lifetime. 15% of men with prostate cancer have a normal PSA. 2  There is no conclusive evidence that detection of early prostate cancer leads to longer survival. 3  The test cannot distinguish between aggressive and slow-growing cancers and may detect tumours that would not otherwise become evident in the patient's lifetime.