Large Malignant Phyllodes Tumor With Rapid Growth During Pregnancy: Images of a Case

Abstract

with focal areas of necrosis (Fig. 1a). Microscopically the tumor cells were arranged in sheets separated by fibrous septae (Fig. 1b). The cells were polygonal to ovoid cells had moderate amount of clear cytoplasm, oval nuclei with moderate pleomorphism, inconspicuous nucleoli, and 4-6 mitosis per high power field with areas of necrosis (Fig. 1c). The tumor involved the overlying skin and was fungating through it; however the nipple and areola were uninvolved. No areas suggestive of adenomyoepithelioma were seen. The cells were negative for glycogen, mucin, and lipid. On immunohistochemistry the cells expressed smooth muscle actin (SMA) and S-100 ( Fig. 2a, b) and weekly expressed Her 2 Neu and were negative for estrogen and progesterone receptor. Thus a final diagnosis of myoepithelial carcinoma was made.Malignant myoepithelioma (MM) can be seen in association with adenomyoepithelioma, but only rare cases of pure MM have been reported. It is commonly seen in 53-81 years of age, as a firm, rubbery, painless palpable tumor, which may rarely fungate. Microscopically shows solid proliferation of spindle cells. Immunoreactivity for myoepithelial markers, such as SMA, S-100 protein, CK14 calponin, and caldesmon aids in definitive diagnosis. Differential diagnosis includes other clear cell tumors such as glycogen-rich, lipid-rich, and secretory carcinoma. Glycogen-rich carcinomas show abundant clear cytoplasm that is periodic acid-schiff (PAS)-positive diastase-labile material, and are negative for SMA and S-100. Lipid-rich carcinomas show clear cells, containing lipid, demonstrated by oil red O or Sudan IV methods and are negative for glycogen and mucin. Secretory carcinomas are mainly seen in children; the tumor consists of glands and microcystic spaces that contain abundant pink, foamy secretions with clear or vacuolated cytoplasm. Apocrine and mucinous carcinomas can rarely show clear cell change. Apocrine carcinomas have dense homogenous or granular eosinophilic cytoplasm with apical snouts. Mucinous carcinoma is characterized by malignant cells floating in lakes of mucin. MM of the breast with fungating mass are uncommon tumors and often present a diagnostic challenge, these should also be considered in the differential diagnosis of clear cell tumors of the breast.

Histological type and grade of breast cancer tumors by parity, age at birth, and time since birth: a register-based study in Norway

“…Malignant sarcomas (mainly phyllodes tumor) occurred at significantly higher frequency in women diagnosed <2 years after birth. A rapid growth of a phyllodes tumor during pregnancy has been reported previously [33]. Patients with phyllodes tumors have in general been found to have a good prognosis [27,34], except those with large and poorly differentiated tumors [35,36].…”

A Case of a Giant Borderline Phyllodes Tumor Early in Pregnancy Treated with Mastectomy and Immediate Breast Reconstruction

“…Recognizing this potential continuum of transformation, in 2003, the World Health Organization proposed an international grading classification for (Table 1), the majority of cases presenting in the second half of pregnancy (6/9 cases). Including our case, six were malignant (1,2,(11)(12)(13)(14), one was borderline, and three were benign (15,16) (Table 1). The median malignant tumor size was 17 cm, ranging from 4 to 21 cm.…”

“…A comprehensive literature search revealed nine cases of phyllodes tumors during pregnancy (Table ), the majority of cases presenting in the second half of pregnancy (6/9 cases). Including our case, six were malignant , one was borderline, and three were benign (Table ). The median malignant tumor size was 17 cm, ranging from 4 to 21 cm.…”

Malignant Phyllodes Tumor Including Aneurysmal Bone Cyst-Like Areas in Pregnancy - a Case Report and Review of the Literature

“…A PT may present during pregnancy like all other breast tumors, but this is very rare. To the best of our knowledge, 8 cases of PT related to pregnancy have been reported in the literature [2,3,4,5,6,7,8,9]. We report another malignant PT in a 37-year-old newly delivered woman.…”

“…Only a few cases of PTs during pregnancy have been reported in the literature between 1998 and 2011 [2,3,4,5,6,7,8,9]. The median age of the patients was 31 years.…”