RECIST (Response Evaluation Criteria in Solid Tumors) is used in all oncology clinical trials with solid tumors. The main purpose of RECIST is to have consistency in tumor evaluation in clinical trials and make sure that all tumors are assessed using the same standard. Without RECIST the data from different countries or even different hospitals participating in the same study will vary to such extend that the results will not be comparable.  

Although radiology teams do not have any issues using the latest version of RECIST 1.1 often study coordinators and data managers at the hospitals who are involved in data entry do not have enough experience with solid tumor criteria or are confused with RECIST 1.0. Inadequate data entry could be a serious challenge in data review and analysis and often result in additional work for clinical trial team and radiology team who have to review again the all radiology data.

What are the most common RECIST 1.1 data entry issues?

1. Lesion description should be the same for all assessments – for example, if you have lesion description “left axillary lymph node”, it should be the same for all assessments. If there is a discrepancy in radiology report you have to contact radiology team for clarification. 

2. Lots of target lesions per organ – While RECIST 1.0 allowed up to 5 target lesions per organ in RECIST 1.1 this was reduced to 2 target lesions per organ. Please note that lymph system is considered as “1 organ” and if you have more than 2 lymph nodes listed as target lesions you will need to contact radiology team for clarification.

3. Non-measurable lymph nodes entered as measurable – lymph nodes are pathologically enlarged is they are >10 mm in short axis diameter (SAD). In order nodal lesion to be considered measurable it should be ≥ 15 mm in SAD.

4. Some bone and cystic lesions could be measurable – lytic or lytic-blastic bone lesions with a soft tissue component and metastatic cystic lesions could be measurable if they meet the minimum size criteria.

5. Inconsistency in “too small to measure” lesions – if the target lesion is too small to be measured it should be entered as “5 mm” (which is the value of slice thickness of most spiral CT scans). However, if the lesion has disappeared it should be documented as “0 mm”. If it is not clear from radiology report, please contact your radiology team for clarification.

6. Inconsistent tumor response data entry: 

  • Complete Response (CR) requires disappearance of all extranodal lesions, regression of all nodal lesions to < 10 mm SAD and normalization of tumor markers level. 
  • Progressive Disease (PD) is assessed when the sum of the diameters has increased by ≥ 20% and ≥ 5 mm from nadir (including baseline if it is the smallest sum). 
  • Recurrence of Lesions – For patients with Complete Response (CR) reappearance of a lesion would be considered Progressive Disease (PD).
  • Unable to assess – For example, if one of the target lesions has status “unable to assess” then the overall status of the target lesions should also be “unable to assess”. Same principle applies for non-target lesions. Please note that this could change your overall tumor response as well.

If you have any doubts about radiology data entry always contact your radiology team for guidance or clarification.

Author: Olga Peycheva

Olga is a clinical research professional who has been working in clinical research since 2005. She has extensive experience in clinical research in Eastern and Western Europe. 

Originally published on 1 Oct 2015