hyperpigmentation on posterior aspect of the neck

answer

the question is basically a 2 step question..first it want's u to identify what the patient is having??

it is- Acanthosis Nigricans-defined as an asymptomatic area of skin darkening and thickening..(may be associated with pruritus)
Next- u should know common malignancies associated with it-
out of the options given,breast,stomach,lung,uterus are known to be associated with this.
so answer is COLON.(ref-F.A.2010,pg 222)

u should also know why this is being seen in this patient,
because acanthosis nigricans is seen in Insulin resistance states...

hyperpigmentation questn contd

another very imp fact to know is in which else endocrine conditions acanthosis nigricans seen-

1-Diabetes Mellitus
2-Cushing's disease
3-polycystic ovarian disease