Increased asymmetry with larger breast size following the oncoplastic parallelogram mastopexy lumpectomy for cancer

The parallelogram mastopexy lumpectomy (PML) was named from its rounded parallelogram skin incision. ¹ This procedure was conceptualized based on Veronesi's “quadrantectomy” with its radially oriented, full‐thickness glandular excision. ² Subsequent undermining of the breast gland with reapproximation of the tissues at the chest wall, that is, mastopexy closure, reduces the extent of postoperative skin retraction and cavitation, but may lead to asymmetry requiring a contralateral breast lift and/or reduction for symmetry restoration. ¹ , ³ The Breast Retraction Assessment (BRA) test quantifies the degree of cosmetic asymmetry by measuring the distance of nipple‐areolar complex deviation of the treated breast compared with the normal breast (Figure 1). ⁴

FIGURE 1.

Breast retraction assessment (BRA) for the PML. ⁴ From the sternal notch and median line of chest, the nipple of normal breast was localized by x‐axis and y‐axis at a₁ and b₁. The expected neutral position (a₂, b₂) of the operated breast would be the opposite side of a₁ and b₁. BRA was the distance (cm) of retraction

Among 123 women with breast cancer who underwent PML resections between 2009 and 2015, 86 had formal breast cosmetic assessment including the Breast Retraction Assessment (BRA) test at least 6 months following the completion of radiation therapy. In the original study, Pezner and colleagues found that BRA values ranged from 0 to 3.1 cm among normal (control) subjects and ranged from 0 to 8.5 cm in patients who had undergone surgical resection. ⁴ We therefore defined a favorable BRA measurement to be <3 cm (Figure 1).

The ages of patients were 30–80 years with a mean of 55 years; 91% of women had stage 0, 1, or 2 breast cancers. After surgery, 3 of 123 patients (2.4%) had positive or 1 mm margins; of these, two women underwent mastectomy and one woman had a re‐excision lumpectomy. Most patients (111/123, 90%) had margins greater than 10 mm. Median follow‐up time was 6.5 years (range: 0.4–11.4 years). There were 4 women who developed in‐breast local recurrences and one of axillary lymph node recurrence, yielding a Kaplan‐Meier 5‐year local recurrence‐free survival rate of 97% (95% confidence interval = 91% to 99%). All cases of in‐breast local recurrence, each of whom had >10 mm margins at the first resection, underwent subsequent mastectomy. The 5‐year overall survival rate was 95% (95% confidence interval = 89% to 98%).

Of the 123 patients, 86 consented to receive formal cosmetic evaluation. The results of BRA were compared to multiple factors including age, BMI, estimated breast volume, clinical tumor size, tumor location, and stage (Table 1). The women with significant breast retraction (BRA >3 cm, n = 36) had a larger breast volume (mean = 902 cm³, 95% confidence interval = 791–1012 cm³) compared with those of women without significant asymmetry (BRA ≤ 3 cm, n = 50, mean breast volume = 619 cm³, 95% confidence interval = 543–695 cm³, p < 0.001). Women with significant asymmetry (BRA > 3 cm) were more likely to have stage III cancers (11% to 2%), while fewer had stage 0 cancer (3% to 26%, p = 0.014). Multivariate analyses (including parameters of age, tumor size, breast volume, BMI, location, and stage) revealed that breast volume was an independent parameter predicting breast asymmetry of BRA >3 cm (p < 0.001). In the linear regression analysis, there was a moderate positive correlation between breast volume and BRA, r(95) = 0.394, p < 0.001. When two outliers of large BRA (>13 cm) were deleted, the positive correlation persisted with r(95) = 0.377 (p < 0.001).

TABLE 1.

Cosmetic outcomes by breast retraction assessment (n = 86)

Patient characteristics	BRA > 3 cm (n = 36)	95% CI or percentage	BRA ≤ 3 cm (n = 50)	95% CI or percentage	p values
Mean age (year)	58	54–62	54	51–57	0.093
Breast volume (cm3)	902	791–1012	619	543–695	0.000
Body mass index	25	24–27	24	23–25	0.076
Tumor size					0.956
≤1 cm	12	33%	19	38%
1–2 cm	18	50%	23	46%
2–5 cm >5 cm	6	17%	8	16%
Tumor location					0.464
Upper outer	20	56%	28	56%
Upper inner	7	19%	14	28%
Lower	9	25%	8	16%
Stage					0.014
0	1	3%	13	26%
I	17	47%	19	38%
II	13	36%	16	32%
III	4	11%	1	2%
IV	1	3%	1	2%

Abbreviation: 95% CI, 95% confidence interval.

Chagpar and colleagues showed in a prospective randomized trial that cavity shaving reduces the rate of positive margins (19% vs. 34%, p = 0.01) and need for surgical re‐excision (10% vs. 21%, p = 0.02). ⁵ By contrast, our PML series shows a positive margin and re‐excision rate of 2.4%, which compares quite favorably to routine margin shaving. After oncoplastic breast‐conserving surgery, local recurrences have been reported to occur in 0% to 7% of patients. ⁶ Our 5‐year local recurrence‐free survival rate was 97% and was comparable to those of previous reports.

Asymmetry is a practical cosmetic feature to measure, because it can be surgically repaired (if so desired by the patient) using a contralateral breast lift and/or reduction. Boost irradiation had been reported to have adverse effect on the cosmetic result with breast conservation therapy. ⁷ All of our patients with invasive breast cancer underwent whole breast radiotherapy with a boost dose to the lumpectomy site. The slightly better outcome for women of noninvasive stage 0 cancer may have resulted from not receiving boost radiation to the lumpectomy site.

Mastopexy was originally a cosmetic glandular reshaping surgery in treating breast ptosis. Among the patients of larger breast volume, which was frequently associated with ptosis, mastopexy might bring about lifting effects on their nipple‐areolar complex, which was demonstrated in our analyses of BRA. The potential need for surgical correction by reducing the opposite breast should be discussed with patients for whom asymmetry is a predictable or likely postoperative outcome.