Additional Info

  • CPT Code(s)***: 88365 (Global); 88365TC (Technical Component Only)
  • Methodology: In Situ Hybridization (ISH)
  • Specimen Requirements:

    5 formalin-fixed (10% neutral buffered formalin), paraffin-embedded tissue sections on "plus" (positively) charged slides or a paraffin tissue block.

  • Shipping Instructions:

    Ship blocks with cold pack. Ship formalin-fixed, paraffin-embedded tissue with an absorbent, secondary containment pack.

  • Clinical Utility:

    The demonstration of kappa and lambda light chains in formalin fixed paraffin embedded tissue can be used to assess clonality of a lesion of B cell origin. Mature B cells do not actively produce kappa and lambda light chains. They are only expressed as proteins on the cell surface, and therefore will not stain with ISH. However B cells which terminally differentiate into plasma cells which actively produce kappa and lambda will be detected by ISH, as high levels of kappa and lambda mRNA will be present in these cells.

  • Turnaround Time: 24-36 Hours
  • ***: CPT codes are based on American Medical Association guidelines and are for informational purposes only. The billing party is responsible for CPT coding.