Metachronous breast cancer

Case contribution: Dr Radhiana Hassan


  • A 58 years old
  • History of right breast cancer 9 years ago
  • WLE, axillary clearance and radiotherapy treatment (in another hospital)
  • No chemotherapy or hormonal therapy after that
  • Complaint of recently felt left breast lump

Mammogram findings:

  • Moderately dense breasts (BIRADS B) with symmetrical pattern
  • A high density mass at left lower inner quadrant (arrows)
  • Lobulated appearance with no associated suspicious clustered microcalcification
  • A density and stromal distortion at right breast from previous operation
  • No skin thickening. No abnormal axillary nodes.

Ultrasound findings:

  • A suspicious mass at Lt6H measuring 23x18x16 mm
  • It shows irregular outline with finger-like infiltration
  • Posterior shadowing is also seen
  • No abnormal vascularity
  • No abnormal axillary node

HPE: invasive carcinoma, no special type

Diagnosis: Metachronous breast cancer


  • Metachronous breast cancers are two breast cancers that occur in either breast in two different time periods.
  • Others defined metachronous as those diagnosed after 6 months from the first BC diagnosis in the contralateral breast or in the same breast but with different histology.
  • The prevalence of metachronous breast cancer is 5-7%
  • Bilaterality is greatest with invasive lobular carcinoma
  • Metastasis to the breast from opposite breast is one of the cause especially with other evidence of metastasis
  • The risk of developing metachronous contralateral carcinoma can be 0.9% per year, with a cumulative risk of 12% at 15 years. Thus, support continuous long term cancer surveillance.
Author: radhianahassan