-
Possible Association: While overwhelmingly caused by dandruff, psoriasis, or folliculitis, intense, recalcitrant scalp itch has been reported in cases of brain tumors or CNS lymphomas due to direct pressure or inflammation. This is exceptionally rare.
5. The Genital or Anal Area
-
Possible Association: Persistent itch here must first rule out common infections (fungal, bacterial), skin conditions (lichen sclerosus), and STIs. Rarely, it can be associated with anal, vulvar, or penile cancers, or Paget’s disease of the skin.
6. The Trunk and Torso (Generalized)
-
Possible Association: A generalized itch that seems to come from “under the skin” with no rash is a classic description of paraneoplastic itch, potentially linked to lymphomas (Hodgkin and non-Hodgkin), leukemias, or solid tumors like gastric, lung, or breast cancer.
7. The Skin All Over (Generalized Pruritus) – The Most Common Warning Sign
-
This is the most frequently cited pattern associated with internal malignancy. It is a whole-body itch, often worse at night, and unrelieved by scratching. It is most strongly associated with:
-
Hodgkin Lymphoma (affects up to 30% of patients).
-
Polycythemia Vera (affects up to 50% of patients).
-
Other lymphomas, leukemias, and cancers of the liver, pancreas, bile ducts, and kidney.
-
8. Inside the Ear Canals
continued on the next page
