I have read with great interest the retrospective single-center review evaluating the oncologic safety of autologous fat grafting as an additional reconstructive modality in patients undergoing mastectomy and implant/autologous breast reconstruction published by Cohen et al.1 I have a few concerns to share with the authors regarding the validity of conclusions.
The authors have evaluated the breasts separately in the individual patients without respect to the pathologic condition in the opposite breast. The contralateral mastectomy in a patient who has presented with breast cancer is considered as prophylactic mastectomy and yet was classified the same as a bilateral mastectomy performed in the BRCA patient. These two mastectomies, although both can be considered prophylactic mastectomies, are a heterogeneous group and in my opinion should not be pooled together.
The authors reported a significantly higher number of cases of ductal carcinoma in situ and lower cancer stage in the autologous fat grafting group, which demonstrates that the groups were not comparable in terms of pathology.1 Pathologic stages were very different between the groups; 34.6 percent stage II and III disease in the autologous fat grafting group, yet 43.9 percent of the patient without autologous fat grafting had stage II and III disease.1 With this difference in pathologic stages between the groups, conclusions should be viewed with caution.
In the current study, a unified treatment protocol was not followed because the protocol was selected by several different oncologists. Thus, the autologous fat grafting group had a significantly decreased incidence of hormone replacement therapy for both therapeutic (58 percent versus 69 percent; p = 0.01) and prophylactic groups (41.9 percent versus 62.9 percent; p = 0.001).1 The autologous fat grafting therapeutic group had higher rates of nipple-sparing mastectomy (33 percent versus 22 percent), and a lower rate of axillary node dissection (21 percent versus 31.9 percent). As a result, the surgical procedures were not completely comparable.1 Differences in the rate of node dissection between the groups not only confirms intergroup differences in disease stages, but also raises concerns of differences in accuracy of the nodal staging and future risk of local recurrence between the two groups. Patients who underwent autologous fat grafting were also significantly younger in the current study. Age is proposed as an independent predictor for breast cancer recurrence by some authors.2,3 Given the differences in the important characteristics of age, type and stage of abnormality, treatment modalities (surgery and hormone therapy), can we expect the study to be able to yield a valid comparison?
The authors compared receptor status (positive versus negative) for individual hormones, but they did not examine for the frequency of triple-negative breast cancer category, high-grade neoplasia, and Ki-67 marker between the groups. Some authors have proposed menopausal status and triple-negative breast cancer as determinants of the locoregional disease-free survival and breast cancer–specific survival following mastectomy.5 We suggest addition of the above factors in any future comparison between the autologous fat grafting group and their controls.
A concern always exists that autologous fat grafting may interfere with the possibility of early detection of the breast cancer recurrence and may also impact the accuracy of imaging modalities and physical examination during follow-up. In this study, mean time to recurrence was significantly longer in the autologous fat grafting group (52.3 months versus 22.8 months). Although authors have used this finding in support of oncologic safety of autologous fat grafting, we caution and remind them that an alternative explanation could be a delay in the diagnosis of recurrence canceled by autologous fat grafting. Only more lengthy long-term follow-up (i.e., 12 to 15 years) may address this concern.
Demicheli et al. reviewed a total of 1173 patients undergoing mastectomy for evaluation of the timing of breast cancer recurrence.6 These patients did not undergo any adjuvant treatment. The first recurrence peaked at approximately 18 months, with a second peak at approximately 60 months. Subsequently, the recurrence rate tapered to a plateau-like tail extending up to 15 years after surgery. The current follow-up time would certainly miss the timing of the second peak recurrence and events occurring afterward. Future studies with more controlled, comparable tumor and patient characteristics and preferentially a prospective randomized design with a longer follow-up are required to shed light on the oncologic safety and impact of autologous fat grafting in the patients undergoing mastectomy and reconstruction for breast cancer.
The author would like to thank Edward Luce, M.D., for providing editorial assistance.
The author has no financial disclosure to report in relation to the content of this communication.
Alireza Hamidian Jahromi, M.D.Department of Plastic and Reconstructive SurgeryUniversity of Tennessee–Memphis910 Madison Avenue, Suite 315Memphis, Tenn. firstname.lastname@example.org
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2. El Chediak A, Alameddine RS, Hakim A, et al. Younger age is an independent predictor of worse prognosis among Lebanese nonmetastatic breast cancer patients: Analysis of a prospective cohort. Breast Cancer (Dove Med Press) 2017;9:407414.
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5. Li Q, Wu S, Zhou J, et al. Risk factors for locoregional recurrence after postmastectomy radiotherapy in breast cancer patients with four or more positive axillary lymph nodes. Curr Oncol. 2014;21:e685e690.
6. Demicheli R, Abbattista A, Miceli R, Valagussa P, Bonadonna G. Time distribution of the recurrence risk for breast cancer patients undergoing mastectomy: Further support about the concept of tumor dormancy. Breast Cancer Res Treat. 1996;41:177185.