Contradictions in women's health care provision: a case study of attendance for breast cancer screening.

Breast cancer screening facilities operated by the Ontario Breast Screening Program (OBSP) have recently been added to the existing geography of diagnostic mammography facilities in hospitals and private clinics in Eastern Ontario. While diagnostic facilities require a physician's referral for access, the new centres offer mammograms by self-referral. Other work has shown the utilization of mammography screening services to be quite low despite widespread acceptance of early diagnosis through mammographic screening as the best method to lower breast cancer mortality. Major findings are that spatial variation does exist in attendance rates in the townships and census tracts surrounding the screening centre. At the regional level, physician referral patterns and the presence of local diagnostic mammography units appear to affect the uptake of screening at the Kingston facility. The individual level analysis confirms the importance of the primary care physician's referral with two-thirds of the client sample indicating that they were referred for screening by their family physician. The sample of clients are also very mobile women who have comparatively greater access to financial resources than other women of screening age. The results of ecological and individual level analyses of attendance at OBSP's Kingston Centre reveal contradictions in the provision of this service. Spatially, the centres follow a location pattern of a much higher order health facility yet women are expected to include screening as part of their routine care. Attenders at the Centre were found to be of higher socioeconomic status, married and have access to a private automobile. The finding that the primary care physician's referral is an important prerequisite for attendance raises questions about the feasibility of providing health care for women which encourages individual responsibility for health within the existing paternalistic health care system.

Photodynamic therapy with endogenous protoporphyrin IX: basic principles and present clinical experience.

5-Aminolaevulinic acid (ALA) is a precursor of protoporphyrin IX (Pp IX) in the biosynthetic pathway for haem. Certain types of cells have a large capacity to synthesize Pp IX when exposed to an adequate concentration of exogenous ALA. Since the conversion of Pp IX into haem is relatively slow, such cells tend to accumulate photosensitizing concentrations of Pp IX. Pp IX photosensitization can be induced in cells of the epidermis and its appendages, but not in the dermis. Moreover, since ALA in aqueous solution passes readily through abnormal keratin, but not through normal keratin, the topical application of ALA in aqueous solution to actinic keratoses or superficial basal cell or squamous cell carcinomas induces Pp IX photosensitization that is restricted primarily to the abnormal epithelium. Subsequent exposure to photoactivating light selectively destroys such lesions. In our ongoing clinical trial of ALA-induced Pp IX photodynamic therapy, the response rate for basal cell carcinomas following a single treatment has been 90% complete response and 7.5% partial response for the first 80 lesions treated. The cosmetic results have been excellent, and patient acceptance has been very good.