Skip to Main Content

We have a new app!

Take the Access library with you wherever you go—easy access to books, videos, images, podcasts, personalized features, and more.

Download the Access App here: iOS and Android. Learn more here!

Response Evaluation Criteria in Solid Tumors

ABBR: RECIST. A means of evaluating whether a cancer shrinks during radiotherapy or chemotherapy by measuring the size of the tumor with imaging techniques before and during treatment. Tumors that shrink are classified as showing either a complete response (CR) or a partial response (PR). Some patients have no response to treatment, i.e., they either have no visible effect on tumor size (stable disease [SD]), or their tumor enlarges despite treatment (progressive disease [PD]).

response-guided therapy

Treatment that is continued or stopped depending on the patient’s clinical or biochemical responses. For example, during treatment of chronic hepatitis C virus infection, continuation of treatment depends on an inability to detect live virus after a specified number of weeks.


(rē-spŏn″sĭ-bĭ′lĭ-tē) 1. Accountability. 2. Trustworthiness.

responsible party

The individual whose actions or inactions caused injury, harm, or damage to something or someone.


(rest) 1. Repose of the body as in and caused by sleep. 2. Freedom from activity, as of mind or body. 3. To lie down; to cease voluntary motion. 4. A remnant of embryonic tissue that persists in the adult.


A measurement of the extent of a patient’s tumor burden after the completion of an initial course of cancer treatment.


(res″tĕ-nō′sĭs) [re- + stenosis] Recurrence of a blockage in a previously opened heart valve, blood vessel, or tube.

REST factor

repressor element-1 silencing transcription factor.

rest home

Nursing home.


(rĕs′tĭ-form) [L. restis, rope, + forma, shape] Ropelike; ropeshaped.

restiform body

SEE: under body.


1. Inactive, at rest. 2. Neither in motion nor exerting any muscular effort.

resting energy expenditure

Basal metabolic rate.

restitutio ad integrum

(rĕs″tĭ-tū′shē-ō ăd ĭn-tĕ′grŭm) [L.] Complete restoration to health.


(res″tĭ-too′shŏn, -tū′) [L. restitutio, restoration, rebuilding] 1. The return to a former status. 2. The act of making amends. 3. The turning of a fetal head to the right or left after it has completely emerged through the vagina in order to align the head with the spine. SYN: movement of restitution; external rotation.

restless legs syndrome

A condition marked by an intolerable creeping sensation or itching in the lower extremities and causing an almost irresistible urge to move the legs. The symptoms are worse at ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.