premalignant (Solar keratosis, arsenical keratosis
, Bowen's disease) or malignant (Squamous cell carcinoma, rarely, basal cell carcinoma, metastatic renal carcinoma, granular cell tumor, sebaceous carcinoma or Kaposi's sarcoma.
5 The disease should be differentiated from arsenical keratosis
, porokeratotic eccrine ostial and dermal duct nevus, porokeratosis palmaris et plantaris disseminate and punctate porokeratotic keratoderma which may have same presentation.
appears as diffuse thickening involving palms and soles, alone or in combination with nodules usually symmetrically distributed.
Our patient came from an endemic area where levels of arsenic are high in drinking water and had features of arsenical keratosis
for past fifteen years along with metastatic testicular cancer at the time of presentation.
Hypomelanotic guttate macules on diffuse hyperpigmentation and arsenical keratosis
may be formed.
Similarly the premalignant and malignant conditions associated with the horns7,8 include adenoacanthoma, actinic keratosis, Bowen's disease, arsenical keratosis
, Paget's disease, Kaposi sarcoma, malignant melanoma, sebaceous carcinoma9 and squamous cell carcinoma.