CPT® Code 88369

Add-On Code

Morphometric analysis, in situ hybridization (quantitative or semi-quantitative), manual, per specimen; each additional single probe stain procedure (List separately in addition to code for primary procedure)

Morphometric analysis, in situ hybridization (quantitative or semi-quantitative) is a specialized laboratory technique utilized primarily by pathologists and geneticists to visualize and analyze specific genes or segments of genes within biological specimens. This method employs fluorescent tagging to detect genetic abnormalities, which may include translocations, deletions, duplications, amplifications, and inversions on chromosomes, as well as in hematologic cells and solid tumor cancers. The process begins with the fixation of cells onto a microscope slide, followed by treatment to denature the DNA, converting it into single strands. A short sequence of single-stranded DNA, known as a probe, is designed to match a specific portion of the target gene(s) and is tagged with fluorescent labels. This probe is then applied to the slide, where it hybridizes, or binds, to the complementary DNA strands present in the specimen. After allowing sufficient time for hybridization, the slide is washed to eliminate any unbound probe, ensuring that only the specifically hybridized areas remain. The final step involves manual examination of the slide under a microscope, where the pathologist or geneticist can identify and interpret the presence of genetic abnormalities. This detailed analysis is crucial for determining patient eligibility for targeted treatments, planning appropriate treatment courses, and monitoring the effectiveness of ongoing therapies. For billing purposes, CPT® Code 88368 is used for the initial single probe stain performed, while CPT® Code 88369 is designated for each additional single probe stain procedure conducted on the same specimen.