Assessment of CGH-Array Usefulness in Metachronous Tumors
Francois Le Loarer, Pauline Lagarde, Agnes Neuville, Jean Michel Coindre, Frederic Chibon. Rouen University Hospital, Rouen, France; Institut Bergonié, Bordeaux, France
Background: Poorly differentiated metachronous tumors challenge pathologists ability to distinguish confidently a recurrence of the first tumor from a distinct tumor event. Traditional approach is based upon conventional morphology supplemented by immunohistochemistry. The use of molecular tools on a routine basis has long been hindered by the requirement of frozen material. CGH-array protocols have been recently adapted to comply with formalin-fixed paraffin-embedded (FFPE) material. We assessed CGH array technical feasability and diagnostic utility in a series of metachronous tumors.
Design: We selected seven consecutive cases of metachronous malignancies submitted for expert review from December 2010 to April 2011. In all cases, the second event was a poorly differentiated sarcomatoid malignant tumor. CGH-array was performed on Agilent platform with 60k oligo-array. The molecular biologist compared blindly the genomic profiles of couples of metachronous tumors to render a diagnosis of recurrence of the first tumor or distinct tumor events.
Results: Two out of seven cases provided poor quality genomic DNA precluding confident CGH analysis. Technical limitations were due to cellularity of one specimen and poor quality fixation step in the other one. Apart these limitations, we reached high quality CGH-array analysis equivalent to frozen sample-based analysis. Genomic-based diagnoses were in accordance with morphology in three cases out of five and contradicted morphology in one case. No definitive genomic diagnosis could be rendered in one case.
|Gender - Age*||Primary site||Date of primary||Diagnosis of primary||Second site||Histologic diagnosis||Genomic analysis|
|female 63||maxilla||2010||sarcomatoid carcinoma||adrenal gland||metastasis||same tumor|
|male 56||kidney||2000||clear cell carcinoma||maxilla||pleomorphic sarcoma||distinct tumor|
|male 70||tongue||2004||squamous carcinoma||gengiva||recurrence of carcinoma||distinct tumor|
|female 61||meninges||2007||meningioma||adrenal gland||metastasis||same tumor|
|male 69||cervical lymph node||2008||squamous carcinoma||breast||metastasis||NA|
|female 68||kidney||2008||papillary carcinoma||humerus||metastasis||NA|
|male 76||kidney||2007||papillary carcinoma||liver||metastasis||uncertain|