Bröker Mirelle E E, Bekken Joost A, Reijnen Michel M P J, Bröker Willem F H L
Erasmus MC, afd. Chirurgie, Rotterdam, The Netherlands.
Ned Tijdschr Geneeskd. 2011;155(41):A3638.
There are two types of ectopic breast tissue: accessory breast (polymastia) and aberrant breast tissue. Breast cancer may arise in any type of ectopic breast tissue, although rarely.
A 50-year old woman had a palpable mass near an accessory nipple. Physical and X-ray examination suggested a benign tumour, but after excision and pathological examination it turned out to be breast cancer. After follow-up examination a re-excision with a sentinel node procedure was performed. There was no indication for adjuvant therapy.
Due to the atypical location, the diagnosis 'breast cancer in an accessory breast' is usually made in a late stage. Due to the small amount of breast tissue, invasion of skin or underlying tissue is more common. Drainage of lymph fluids may be different as well, which has to be taken into account when performing a sentinel node procedure. Also, lymph node metastases may present in the ipsilateral mamma. These particulars should be taken into account in the treatment of cancer in ectopic breast tissue.
异位乳腺组织有两种类型：副乳腺（多乳症）和迷走乳腺组织。乳腺癌可发生于任何类型的异位乳腺组织，尽管很少见。
一名50岁女性在副乳头附近可触及肿块。体格检查和X线检查提示为良性肿瘤，但切除并经病理检查后发现是乳腺癌。随访检查后进行了前哨淋巴结活检的再次切除手术。没有辅助治疗的指征。
由于位置不典型，“副乳腺乳腺癌”的诊断通常在晚期做出。由于乳腺组织量少，皮肤或深层组织受侵更为常见。淋巴液引流也可能不同，在进行前哨淋巴结活检时必须予以考虑。此外，同侧乳房可能出现淋巴结转移。在治疗异位乳腺组织的癌症时应考虑到这些特殊情况。
