|Home | About | Journals | Submit | Contact Us | Français|
Phyllodes tumors are fibroepithelial lesions and malign forms are rare neoplasms with lower than 1% of all primary breast tumors. Malign forms are usually behaves like sarcomas because they occur in the stroma of the breast. Also proliferation of epithelium occurs and even it is less often, the epithelial component of phyllodes tumors can transform into malignancy too. This epithelial malignancies are usually in the form of infiltrative carcinomas and non-invasive tumors arising in benign phyllodes tumors are much rarer but can be seen. Literature include very few cases about this situation and cases are usually old woman. We report a 19-year old patient who was diagnosed with ductal carcinoma in situ arising in benign phyllodes tumor of the breast.
Phyllodes tumors are a group of uncommon breast tumors involving biphasic proliferation of stroma and breast epithelium (1). The majority present a benign process but with increasing cellularity, invasive margins and actual sarcomatous behaviour, they can represent different characteristics from borderline to a malignant process (2, 3). Histologically they seem similar to fibroadenomas but are typically organized in leaf-like structures because of more cellular stroma. They usually appear as a fast growing, firm and well demarcated mass. While local excision is adequate for benign phyllodes tumors, surgical margins must be over 1 cm for borderline tumors. Malignant phyllodes tumors are treated like sarcomas and en bloc surgical resection is recommended. Recurrence rates for benign, borderline and malignant phyllodes tumors are %17, %25, %27, respectively (4, 5). Malignant transformation of the tumor usually occurs in the stromal part of the tumor but the epithelial component of phyllodes tumors can transform into a malignancy too (6). Even this transformation is rare, most of them are infiltrative ductal carcinomas (2). Documented literature about ductal carcinoma in situ arising in phyllodes tumor is a rare situation (7–16). We report a 19-year old patient who was diagnosed with ductal carcinoma in situ arising in a benign phyllodes tumor of the breast.
A 19-year old woman who discovered a painless mass in her right breast was admitted to Ankara Oncology Training and Research Hospital. She had no family history of cancer. The mass had grown rapidly over a 1 month period and was palpated in the upper outer quadrant of the right breast. It was well-defined, freely movable and 2.0×2.0 cm in size. The tumor was nonadherent to the skin and there were no palpable lymph nodes in the axilla or supraclavicular fossa on physical examination. Breast ultrasonography showed a 23×12 mm in size, regular, heterogenous, hypoechogenic mass in her right breast and the radiology department suggested excision of the lesion. Mammography was not performed because of patient’s age. The serum levels of tumor markers (CA 15-3, CEA) were within normal range. The tumor was locally excised under local anaesthesia. The patient had a rapid recovery and was discharged on the same day.
The final pathology result was benign phyllodes tumor. The tumor was 18 mm in greatest diameter and was well-demarcated. Histologically, the tumor consisted of both epithelial and stromal elements. Stromal elements showed mild cellularity and 1–2 mitoses per 10 high power fields. Expression of Ki-67 nuclear antigen was also examined and Ki-67 proliferative activity index was %5–10 in the stromal component. A focus of an 8 mm ductal carcinoma in situ nuclear grade 2, with a cribriform pattern was observed in the ductal part of the tumor (Figure 1, ,2).2). Immunohistochemically, estrogen and progesterone receptors were positive in the ductal carcinoma in situ component. Based on these findings, the tumor was diagnosed as ductal carcinoma in situ arising in a benign phyllodes tumor.
Consequently, we administered radiation therapy and endocrine therapy with tamoxifen citrate to our patient for in situ carcinoma and she remains well during a 3 year follow-up period.
Phyllodes tumors of the breast are fibroepithelial lesions that account for fewer than 1% of all breast neoplasms. They are usually classified into three categories like benign, borderline and malignant. This classification is based on some histological factors such as stromal cellularity, cellular atypia, mitotic activity, stromal overgrowth, tumor necrosis and the nature of the tumor margins (6). Because malignant transformation of a phyllodes tumor mostly occurs in the stromal component, many studies are centred upon this component.
The defining features of ductal carcinoma in situ include; malignant cytologic features (monomorphic or pleomorphic), involvement of two duct cross-sections and/or the sum of the duct diameters involved in the lesion greater than 2 mm, and malignant cells confined to the basement membrane inside the duct. Ductal carcinoma in situ arising from the ducts in phyllodes tumors should be differentiated from the usual epithelial hyerplasia. Usually, hyperplasia of epithelial cells show overlapping proliferation. It was the rigid epithelial bars and cribriform lumina that signified the lesion as atypical epithelial hyperplasia and with the size of the lesion being 8 mm, it reached the definition of ductal carcinoma in situ.
Nio et al. (17) reported 53-year old female patient and Yamaguchi et al. (5) reported 53-year old female patient both with a benign phyllodes tumor with ductal carcinoma in situ. Quinlan-Davidson et al. (18) reported a 53-year old female patient with a borderline phyllodes tumor with tubular carcinoma and lobular carcinoma in situ. Neto et al. (19) reported a 66-year old female with the coexistence of benign phyllodes tumor and synchronous, independent and invasive ductal carcinoma in separate breasts. Although the median age of occurrence of disease is 40–50 years, and the documented literature about ductal carcinoma in situ arising in phyllodes tumor is a rare situation especially in older patients, our case illustrates that this situation can be seen in younger ages. Moreover, our case presented here is the youngest patient with ductal carcinoma in situ arising in phyllodes tumor according to documented in the literature (7–19).
There are different opinions about the carcinomas arising from phyllodes tumor. Malignant transformation of epithelial hyperplasia in the phyllodes tumor is one of them. In 2005, Tan et al. (20) studied the pathology specimens of 335 Asian women with phyllodes tumor and reported the epithelial hyperplasia rate as 74% (247 cases). Even though it is a reliable hypothesis, the relationship between phyllodes tumors and carcinomas is still unknown. Nomura et al. (7) reported a 75-year old case with ductal carcinoma in situ arising in a malignant phyllodes tumor and estrogen and progesterone receptors were both negative in that case.
A variety of therapies were applied to the various cases. These are local excision and local radiation therapy, mastectomy, and axillary lymph node dissection. It appears that mastectomy or local excision was selected according to the size of the phyllodes tumor. Axillary dissection was applied for large phyllodes tumors, but no lymph nodes involved in the cases. Also post-surgical radiation therapy and endocrine therapy were applied. The prognosis for cases of ductal carcinoma in situ within phyllodes tumors is generally favorable, with no deaths yet reported. Axillary lymph node dissection is not part of the standard treatment for phyllodes tumors as lymph node spread is rare, and may thus be restricted to patients suspected of having lymph node involvement by image diagnosis (5, 9, 16).
In situ carcinomas, even infiltrating ones, arising in phyllodes tumors cannot be detected preoperatively in many of the cases. In all patients with suspected phyllodes tumors, even young ones like this case, the radiologists must be aware of the possibility of concurrent carcinoma or in situ carcinoma. It is very difficult to identify this kind of tumor preoperatively because, in many cases, phyllodes tumors encircle the actual malignant or premalignant lesion. Also histopathological examination must be done meticulously because it is very easy to overlook small in situ lesions under the actual pathologic diagnosis of benign phyllodes tumor. As in the stromal component, the epithelial component must be carefully investigated for malignancy.
This case was presented at 16th Annual Meeting of the European Society of Surgery, 22–24 November 2012, İstanbul, Turkey.
Conflict of Interest: No conflict of interest was declared by the authors.
Peer-review: Externally peer-reviewed.
Informed Consent: Written informed consent was obtained from patients who participated in this case.
Author Contributions: Concept - M.K.Ç., E.Y.; Design - M.K.Ç., E.Y.; Supervision - M.A.G., M.Ç.; Funding - M.K.Ç., E.Y.; Materials - M.K.Ç., E.Y.; Data Collection and/or Processing - M.K.Ç., Y.Ö., S.Ç.I.; Analysis and/or Interpretation - S.Ç.I., M.A.G., M.Ç.; Literature Review - M.K.Ç., E.Y., G.G.A.; Writer - M.K.Ç., E.Y.; Critical Review - M.A.G., M.Ç.
Financial Disclosure: The authors declared that this study has received no financial support.