Tumors that metastasize to bone may be remembered using the mnemonic “lead kettle” spelled PBKTL (“Pb” from the Latin plumbum which is the periodic table name for Lead).
- PB-KTL
Mnemonic
- P: prostate
- B: breast
- K: kidney
- T: thyroid
- L: lung

For females, breast and lung are the most common primary sites; nearly 80% of cancers that spread to the skeleton are from these locations. In males, prostate and lung cancers make up 80% of carcinomas metastasizing to bone. The other 20% of primary disease sites in both sexes are: kidney, thyroid, gastrointestinal tract and other locations.
Lytic vs blastic in the “lead kettle” PB-KTL mnemonic
By knowing the typical behavior of the metastatic lesion – lytic or blastic – you can help sort between the types to make the mnemonic even more useful.
- prostate = blastic/sclerotic (induces bone growth)
- breast = mixed pattern
- kidney, thyroid, lung = lytic (induces bone destruction)
Hope that mnemonic helped. Read more medical mnemonics here.