Table 2

Anatomic localization, histological characteristics, and predominant neoplastic cell size in 331 invasive anal squamous cell carcinomas

No. of cancers (% hrHPV-positive)
Women (nNULL =NULL 253)Men (nNULL =NULL 78)
Anatomic localizationa
 Most proximal lesion extent (87%)
  Anal canal, colorectal zone96 (99)21 (90)
  Anal canal, anal transitional zone15 (80)2 (100)
  Anal canal, squamous zone55 (91)17 (71)
  Perianal skin56 (80)25 (28)
P-trendbNULL <NULL 0.001P-trendbNULL <NULL 0.001
 Anal epithelial zones involvedc (87%)
  Anal canal, colorectal zone96 (99)21 (90)
  Anal canal, anal transitional zone36 (92)5 (100)
  Anal canal, squamous zone77 (92)20 (70)
  Perianal skin64 (81)30 (33)
P-trenddNULL <NULL 0.001P-trenddNULL =NULL 0.01
Histological characteristicsa
 Basaloid featurese (95%)
  No117 (87)51 (49)
  Yes122 (94)23 (87)
PNULL =NULL 0.06PNULL =NULL 0.002
 Keratinization (95%)
  No127 (92)31 (84)
  Yes,NULL +NULL (poorly keratinized)54 (94)13 (69)
  Yes, ++ (moderately keratinized)30 (87)12 (42)
  Yes, +++ (well keratinized)28 (82)18 (28)
P-trendbNULL =NULL 0.10P-trendbNULL <NULL 0.001
 Associated AIN (95%)
  No155 (88)54 (50)
  Yes84 (96)20 (90)
PNULL =NULL 0.03PNULL =NULL 0.001
Neoplastic cell typea
 Predominant cell-size in lesion (98%)
  Large48 (81)32 (25)
  Medium97 (93)24 (88)
  Small105 (93)20 (90)
PNULL =NULL 0.04PNULL <NULL 0.001
  • a Numbers do not add up to 253 for women and 78 for men because not all characteristics could be assessed for all specimens. Percentages indicate the proportion of cancer specimens assessable for the individual characteristic.

  • b Mantel-Haenszel χ2 test for trend.

  • c Each cancer specimen examined may extend over more than one of the four epithelial zones.

  • d Wald test for trend based on generalized estimating equations method for correlated data.

  • e Basaloid features comprise eosinophilic necrosis and/or peripheral palisading.