INCLUSION CRITERIA:

1. Documented exceptional response. Reports of radiologic scans or other evidence documenting response will be submitted for review. Cases where response is not assessable (e.g. adjuvant treatment) will not be eligible because the outcome can not be attributed to a specific treatment.
2. Treatment history must be available, for prior treatment and for the drug to which the exceptional response occurred.
3. Patient must meet consent criteria detailed in section VII.2.0. This requires: (i) current ER consent by a living participant not lost to follow-up, (ii) prior consent for future research by a participant not known to be deceased, but lost to follow-up, or (iii) if patient is deceased and did not decline to participate in research at the time of tissue removal for any tissue that would be used in this study, then no consent is required.
4. Tumor sample available that meets study requirements.
5. Required tumor samples MUST exist and be able to be submitted. Investigators wishing to submit samples must not have made agreements that would prohibit the free use of data from such samples. The NCI will provide investigators with a letter for the collaborator amending their existing agreement to allow for the case to be submitted. 5.1 Tumor tissue from prior to administration of the drug to which the exceptional response occurred is required. Ideally this sample will have been collected just prior to treatment, but other prior tissue will be considered. Tissue may be fresh frozen or formalin-fixed paraffin embedded 5.2 Tumor tissue amount must be at least a core biopsy, and meet minimum specimen requirements as described below in METHODS.
6. Encouraged: Normal tissue sample: (optional): Blood or other specimen source for germline sequencing.
7. The tumor samples and clinical data submitted to the Exceptional Responders Database in dbGaP will need to have appropriate agreements in place to allow for the submission. The Exceptional Responders Database can accept clinical data and samples from cases enrolled on a CTEP sponsored clinical trial and cases that were not enrolled on any clinical trial. If the response occurred on a trial that was not CTEP-sponsored, there are existing agreements between the submitting site and the pharmaceutical company. If existing agreements do not allow for the submission of sample and clinical data, the NCI will provide the investigators with a letter that allows the tissue to be used for the Exceptional Responders study if signed by the appropriate collaborator. The letter modifies the existing agreement to include the CTEP IP Option language that would allow the case to be submitted to the Exceptional Responders Database. If the existing agreement cannot be modified and the letter cannot be signed, the proposed case will not be accepted.

EXCLUSION CRITERIA:

Cases or tissue meeting these requirements will not be accepted into this study:

1. Patient's response did not meet criteria for an exceptional response 1.1 Patient's treatment regimen is expected to lead to CR or durable PR in > 10% of patients. 1.2 Patient s duration of response is not > 3x expected median length of response. 1.3 Response not evaluable or not able to be attributed to systemic treatment (e.g.adjuvant treatment)
2. Patient refused consent for use of tissue for research activities included in the Exceptional Responders study.
3. Tumor sample from prior to the exceptional response is not available, or does not meet quality metrics.