The Rare Isolated Solitary Muscle Metastasis of Breast Carcinoma Confirmed by 18F-FDG PET/CT

Abstract

ÖzetMeme kanserinin kas dokusuna metastaz yapması oldukça nadirdir. Kas metastazları ise sıklıkla diğer organ metastazları ile birliktedir. İnvaziv duktal karsinoma sahip, uzak metastazı olmayan lokal ileri meme karsinomlu 51 yaşındaki hastada tanıdan 1 yıl sonra solda sternokleidomastoid kasında 5 cm çapında kitle tespit edildi. Bu lezyondan 2 kez biyopsi yapılmasına rağmen malignite lehine bulgu tespit edilmedi. Ancak klinik olarak metastaz düşünülen hastaya yeniden evreleme amacıyla 18F-FDG PET/BT yapıldı. Sol sternokleidomastoid kasındaki hipermetabolik alandan yapılan tru-cut biyopside osteoklast içeren dev hücreli meme karsinomu tespit edildi. Bizim olgumuz ilk metastazını soliter olarak sternokleidomastoid kasına yapan literatürdeki ilk meme karsinomu olgusudur. Anahtar KelimelerMeme Kanseri; Fluorodeoksiglukoz F18; Metastaz; Kas-İskelet Sistemi AbstractMuscle metastasis of breast carcinoma is a rare condition. It often coexists with other organ metastases. A mass in the left sternocleidomastoid muscle was detected 1 year after diagnosis in a 51-year-old patient with locally advanced invasive ductal breast carcinoma. Although biopsy from this lesion was applied two times, the malignancy was not found. However, the patient had clinicallysuspected metastasis. The 18F-FDG PET/CT was performed for restaging. The tru-cut biopsy from the hypermetabolic area in muscle mass proved the metastasis contained osteoclast giant cell carcinoma of the breast. Our patient is the first case in the literature of the diagnosis of breast cancer with initial solitary metastasis to the sternocleidomastoid muscle.

Malignant Phyllodes Breast Tumor: A Rare Case of Metastasis in Skeletal Muscle Detected on 18-Fluorodeoxyglucose Positron Emission Tomography

“…Atypical distant metastasis from malignant PT of the breast has been reported in the literature [3][4][5][6]. However, there are few isolated reports in the literature emphasizing the usefulness of FDG PET-CT in PT [6].…”

“…Literature review reveals limited case reports in which rare metastatic sites, such as skeletal muscle involvement, are observed. A mass lesion in the sternocleidomastoid detected using FDG PET-CT and confirmed to be the metastasis of invasive ductal breast carcinoma using a tru-cut biopsy has been reported in the literature [ 5 ].…”

“…These can be benign, borderline, or malignant depending on histological characteristics, such as margin involvement, cellularity, mitosis, and cellular atypia [1,2]. Distant metastasis and recurrence are rare among benign and borderline cases; however, they are not uncommon in malignant PT and range from 25% to 40% [3][4][5]. The tumor tends to metastasize via hematogenous spreading.…”

“…The most common sites of involvement are bones, lungs, liver, and heart. Skeletal muscle metastasis is extremely rare in malignant PT [1,5]. Surgery is the preferred treatment for PT [1].…”