DETECTION OF SPECIMEN CONTAMINATION IN ROUTINE HISTOPATHOLOGY BY HLA CLASS-II TYPING USING THE POLYMERASE CHAIN-REACTION AND SEQUENCE-SPECIFIC OLIGONUCLEOTIDE PROBING

This study evaluates the use of human leukocyte antigen (HLA) class II PCR-SSO typing for the investigation of suspected specimen contaminat ion in four routine surgical histopathology cases. Two cases were of p atients undergoing transurethral resection of the prostate gland. The third case was a patient undergoing excision of a subcutaneous small c ell carcinoma. The fourth case was a patient undergoing reversal of a Hartman's procedure for adenocarcinoma of the colon. Tissue was extrac ted from routinely processed formalin-fixed, paraffin-embedded materia l and HLA class II typed, using a non-radioactive polymerase chain rea ction-sequence specific oligonucleotide probe technique (PCR-SSO), usi ng probes specific for the DRB, DQA, and DQB loci. The accuracy of PCR -SSO typing of DNA extracted from paraffin biopsy material was confirm ed by concordant results for DRB, DQA, and DQB typing in five separate control individuals from whom frozen and paraffin lymph node biopsies were available. PCR-SSO typing was also successful in the four study cases and revealed that contamination had occurred in two cases, elimi nating this possibility in the remaining cases. This study demonstrate s that DNA can be reliably amplified and accurately typed from routine ly processed material, and reveals a useful new application for PCR-SS O tissue typing.