cystic hypersecretory carcinoma ( chc ) and cystic hypersecretory hyperplasia ( chh ) were first described in 1984 ( 1 ) . the characteristic features of these lesions are dilated ducts and cysts containing an eosinophilic secretory product resembling thyroid colloid . after the initial report of chc and chh , the entire spectrum of cystic hypersecretory lesions of the breast was described by guerry et al . in 1988 these lesions range from benign chh to the intermediate chh with atypia and the frankly malignant chc . there have been only seven cases of invasive chc reported in the literature ( 1 - 5 ) . a 45-yr - old woman was admitted to the hospital for diagnosis and treatment of a palpable mass in the lower quadrant of the left breast . the mass was soft and focally hard . gross pathologic examination of the excisied specimen revealed an ill - defined , mucoid mass . the cut surface of the mass , which was 4.73.73 cm , revealed multiple cystic spaces , and the cysts were filled with thick , gelatinous secretions . the homogeneous secretions were retracted from the surrounding epithelia , producing scalloped margins ( fig . the lining of the cysts in most areas was of flat or cuboidal epithelium and devoid of cellular atypia ( fig . the epithelium of some cysts showed proliferative change ranging from atypical hyperplasia to intraductal carcinoma , micropapillary type ( fig . 2c ) . the intraductal carcinoma component was accompanied by an invasive component with small solid nests ( fig . histochemical staining of the secretory material in the cysts was positive with periodic acid - schiff ( pas ) and alcian blue . immunohistochemically , the cystic contents were positive for carcinoembryonic antigen ( cea ) ( zymed , san franciscoa , ca , u.s.a immunostains for estrogen and progesterone receptors ( dako , glostrup , denmark , predilute ) and p53 protein ( dako , dilution 1:100 ) were negative in the neoplastic epithelial cells . cystic hypersecretory lesions of the breast have a spectrum of morphologic features ranging from the clearly benign ( chh ) , a combination of benign and atypical epithelium ( chh with atypia ) , to cases that combine benign , atypical , and frankly malignant epithelium ( chc ) ( 2 ) . the characteristic gross features are the formation of dilated ducts and cysts filled with a colloid - like secretion . although cystic hypersecretory lesions have a distinctive gross appearance , it is usually not possible to distinguish chc from chh grossly . if no cytologic atypia is present and the epithelium is flat or cuboidal , the lesion is characterized as chh . invasion is heralded by solid nests of invasive carcinoma and is usually poorly differentiated with no secretory characteristics . as a consequence , total excisional biopsy is required for definitive diagnosis of cystic hypersecretory lesions of the breast . about 50 cases of cystic hypersecretory breast lesions have been reported ( 1 - 7 ) . most cases of chc have been intraductal and only seven cases of invasive chc have been reported ( 1 - 5 ) . one patient developed invasive lobular carcinoma of the contralateral breast 10 yr after ipsilateral mastectomy for invasive chc ( 3 ) . in addition , micropapillary intraductal chc and focal high - grade invasive carcinoma were also observed . our case supports the concept that cystic hypersecretory breast lesions encompass a spectrum of pathologic lesions including chh , atypical chh , chc , and invasive chc . the progression of these lesions from chh , through intraductal chc , to invasive chc may be possible . the differential diagnosis of invasive chc includes secretory carcinoma , mucinous carcinoma , malignant mucocele - like tumor , and metastatic thyroid carcinoma . secretory carcinoma contains vacuolated cytoplasm and more bubbly secretions , which are not typical features of chc ( 8) . mucinous carcinoma and malignant mucocele - like tumor also show cystically dilated ducts ( 9 ) . however , the secretions in these lesions are rather pale and basophilic and do not show linear cracking artifacts .
cystic hypersecretory lesions of the breast are rare . 
 these breast lesions include cystic hypersecretory hyperplasia ( chh ) , atypical chh , and cystic hypersecretory carcinoma ( chc ) . 
 the characteristic features are dilated ducts and cysts filled with thyroid colloid - like eosinophilic secretion . 
 only seven cases of invasive chc have been reported in the literature . here , we report an additional case of invasive chc 
 . the histologic features of the tumor showed both micropapillary intraductal carcinoma and focal high - grade invasive carcinoma in a background of chh . 
 this case suggests that cystic hypersecretory breast lesions encompass a spectrum of pathologic lesions including chh , atypical chh , chc , and invasive chc .