Local control assessment in clinical oncology

The true significance of achieving local control has been a matter for debate among clinical oncologists for many years and still is for those tumors where distant metastases are the major cause of failure and mortality. The assessment of local control appears elusive as it may be conceived as the local eradication of neoplastic cells while this should be confirmed by no risk for recurrence. Tools and procedures are available to assess separately the local response after treatment and at long term. Direct methods are quite different according to the different clinical and pathologic conditions. Complete local responses may be followed by recurrence leading to a different approach: to wait for the appearance of recurrence rather than to pursue a complete response. The diagnostic clinical and instrumental methods while easy in superficial tumors, are complex, expensive and poorly reliable in deep-seated tumors. Thus, in general, any assessment of local control in terms of diagnostic work-up can frequently be difficult and misleading.