The geographical assignment of cancer units: patient accessibility as an optimal allocation problem.

The seminal report A Policy Framework for Commissioning Cancer Services provides the foundation for a major reorganisation of cancer service provision in England and Wales. One central recommendation of the report, the establishment of a tier of specialised cancer units in each Health Authority Region has raised the fundamental question of where those units are to be located. In particular, a declared objective of the report is for services to be planned to maximise their accessibility to patients. This paper demonstrates a classical method (location-allocation modelling) by which the accessibility criterion can be used to determine the optimal number, location and capacity of units for a given cancer site. The method is illustrated with reference to cervical cancer in Trent Health Authority Region. The implications of the method for the guidance of access-related decisions on the placement of cancer services are considered, and the wider relevance of the method to the organisation of service provision in other branches of medicine is suggested.