Small foci of suspected neoplasia, particularly in core biopsies, may cut out on subsequent sectioning of a paraffin block. There are a number of techniques for coping with this problem.
The use of antibody cocktails allows two, sometimes three, antibodies to be assessed n the same section. This has particularly be applied to prostatic core biopsies.
The preemptive cutting of interval sections with mounting onto coated slides. This has cost and labour implications if done routinely.
Immunostaining the original H/E section. If there are several sections on the slide, one or more of the H/E stained sections can be protected by covering with mountant. If the tissue is retained on the original uncoated slide, sections may be lost, particularly with heat-induced antigen retrieval. Alternatively, one or more of the sections may be transferred to a coated slide.
References
1 Hammed O, Humphrey PA. Immunohistochemistry in the diagnosis of minimal prostate cancer. Current Diagnostic Pathology 2006;12:279-291.