Table 2

International Cowden Consortium operational criteria for the diagnosis of CS, Ver 2000

Pathognomonic criteria
Mucocutaneous lesions
 Trichilemmomas, facial
 Acral keratoses
 Papillomatous papules
 Mucosal lesions
Major criteria
Breast carcinoma
Thyroid carcinoma (non-medullary), especially follicular thyroid carcinoma
Macrocephaly (megalencephaly) (say, ⩾95th centile)
Lhermitte-Duclos disease (LDD)
Endometrial carcinoma
Minor criteria
Other thyroid lesions (eg, adenoma or multinodular goitre)
Mental retardation (say, IQ ⩽75)
GI hamartomas
Fibrocystic disease of the breast
GU tumours (eg, renal cell carcinoma, uterine fibroids) or malformation
Operational diagnosis in a person
(1) Mucocutaneous lesions alone if:
 (a) there are 6 or more facial papules, of which 3 or more must be trichilemmoma, or
 (b) cutaneous facial papules and oral mucosal papillomatosis, or
 (c) oral mucosal papillomatosis and acral keratoses, or
 (d) palmoplantar keratoses, 6 or more
(2) 2 major criteria but one must include macrocephaly or LDD
(3) 1 major and 3 minor criteria
(4) 4 minor criteria
Operational diagnosis in a family where one person is diagnostic for Cowden syndrome
(1) The pathognomonic criterion/ia
(2) Any one major criterion with or without minor criteria
(3) Two minor criteria
  • Operational diagnostic criteria are reviewed and revised on a continuous basis as new clinical and genetic information becomes available.