Table 2

Histological techniques used in the assessment of rectal tissue

TechniqueTarget and brief utility
Tinctorial stains
 H&E on multiple blocks/levelsGeneral structure
 Elastic van GiesonConnective tissue (collagen, elastin)
 Congo redAmyloid
 Periodic acid-Schiff±diastaseCarbohydrates and mucins
 MTOCH1*Identification and quantification of neurons and cell morphology (diagnosis of aganglionosis, hypoganglionosis and hyperganglionosis)
 c-Kit (CD117)Interstitial cells of Cajal, mast cells
 CD45/CD3White cells/T lymphocytes: to clarify nature of inflammatory infiltrates in ganglionitis or leiomyositis
 Alpha smooth muscle actin and desminConfirm myocyte loss in myopathies; specific deficiency may also accompany some forms of gastrointestinal neuromuscular diseases
  • *Alternative to the London classification,21 which recommends NSE, PGP9.5 or Hu C/D.