Juvenile papillomatosis is a benign breast lesion with pathologic findings consist of papillomatosis and extensive cyst formation [1,2,3] (Fig. 1). It is first described by Rosen PP et al. in 1980 [3]. Patients have complained of a firm, well-defined, mobile mass in the periphery of the breast without nipple discharge, so clinical findings are very similar to a fibroadenoma [1,4]. It is usually solitary, but occasionally it can be seen synchronous, metachronous, and bilateral [5].

Juvenile papillomatosis is not a well known clinicopathologic entity and has similar clinical findings with fibroadenoma. Because of this, its prevalence is not well known, and it is an underdiagnosed entity [2]. In one study, the prevalence of juvenile papillomatosis was found in 1 of 519 forensic autopsies conducted on virtually all females 14 years or older [6].

Macroscopically, the resected mass is well-circumscribed and has multiple cysts (smaller than 2 cm) within a dense fibrous stroma. Because of this macroscopic appearance, it is also called as swiss cheese disease [1]. Tumor size range from 1 to 8 cm [1,3].

Radiologically it can be seen with mammography, sonography, and magnetic resonance imaging [4]. Detailed information about imaging procedures is discussed in "Findings and procedure details." 

It is called "juvenile" because the mean patient age at diagnosis is 19 years, and it has been diagnosed in patient of 6-48 years of age in literature [1]. In our clinic, we have eight patients. They have been diagnosed 26-58 years of age, and the mean age is 34,625. It is known as 'juvenile' but our clinical experience shows that it can also be seen patients in the postmenopausal period. Because of this reason, juvenile papillomatosis has to be kept in mind even in the postmenopausal period.

Although it is a benign pathology, patients, diagnosed with juvenile papillomatosis, have increased risk for breast cancer [1,2,3,4]. It can be associated with carcinoma in up to 15% of cases. Also, carcinomas detected in nearly 50% of cases in follow-up [4]. Juvenile papillomatosis with a family history of breast cancer, multifocal, and bilateral lesions are related to increased breast cancer risk [5]. In these cases, reported carcinoma types are ductal carcinoma in situ, lobular carcinoma in situ, and juvenile secretory carcinoma [5].

Because of this association between juvenile papillomatosis and breast cancer; radiologists, clinicians, and pathologists have to be aware of this clinicopathological entity. Patients who diagnosed with juvenile papillomatosis have to have more strict and early follow-ups than the normal population [1,4,5].

Treatment of juvenile papillomatosis is surgical. Local excision with negative margins is required to avoid local recurrence [4].