Microcalcification

Associations:

Follow the links to the relevant sections....

From the above benign lists microcalcification is very commonly seen in association with SCLEROSING ADENOSIS, COLUMNAR CELL CHANGE, OLD FIBROADENOMAS & ALH and less commonly with apocrine metaplasia and radial scars.

From the above malignant list microcalcification is particularly common in association with DCIS (much more so than LCIS) and in the invasive component of low grade carcinomas rather than high grade carcinomas.

I am extremely grateful to Dr James Walsh, Consultant Radiologist, Edinburgh, who has commented on this section of the website and has with Pat Forrest contributed some superb radiographs as acknowledged individually.

Practice Points:

• Microcalcification is a common mammographic abnormality often requiring further investigation



• A major component of the specimen load from screening but also seen in the symptomatic setting - usually follow-up patients



• Many radiological patterns of calcification are indeterminate and biopsy is often required



• Microcalcification may be associated with both BENIGN and MALIGNANT processes in the same biopsy:
  
  
  • It is vital to point this out to ensure that the extent of the malignant process is not over-estimated radiologically
  
  
  
• An x ray is often provided with the specimen to guide the pathologist as to the number and nature of the calcs he/she is trying to identify in tissue sections and should stimulate the following questions:



• Have I seen all the calcs that are present on the x ray in the initial levels?
• Do I need to cut more levels? - a good default position is 'Yes'
• What pathological processes do the calcs co-locate with?
• Do the calcs co-locate consistently with a particular pathology? :-



• this is important when trying to map the extent of a process, particularly DCIS


• Do coarse calcs correspond to one pathology and fine calcs with another?



• Remember to use the polariser to look for oxalate calcs


• Calcs may be located within ductal or acinar lumens or in connective tissue stroma



• Most microcalcification (90 - 95%) is composed of calcium phosphate while less commonly (<5%) calcium oxalate (Wedellite)



• Calcium oxalate is easy to miss on routine H&E sections, especially under medium or high power objectives, and is much more easily seen under polarised light. It is most commonly seen in association with apocrine metaplasia.