Objective assessment of aesthetic outcomes of breast cancer treatment: Measuring ptosis from clinical photographs

Abstract

The aesthetic outcome of breast cancer treatment is an important factor in breast cancer survivors’ quality of life. We investigated new quantitative, objective measurements of breast ptosis based on ratios of distances between fiducial points manually identified in oblique and lateral clinical photographs. Ptosis refers to the extent to which the nipple is lower than the inframammary fold. The new objective measures were compared to ratings made using an existing subjective scale. The variability in the objective measurements due to intra- and inter-observer variability in marking fiducial points was shown to be equivalent to less than one point on the subjective ptosis scale.

Introduction

Breast cancer is the most common type of cancer among women in the US, excluding skin cancer. It is predicted that in 2005, there will be 212,118 new cases diagnosed [1]. The breast cancer survival rate has increased because of development of improved detection techniques and treatment methods [2], [3]. Breast reconstructive surgery is a crucial part of breast cancer treatment, which can help breast cancer survivors regain a high quality of life. The American Society of Plastic Surgeons estimates that 74,000 breast reconstructive surgeries were performed in the US in 2002 [4]. Breast cancer survivors are now assured the benefit of breast reconstructive surgeries as well as breast conservation therapies according to the Women's Health and Cancer Rights Act of 1998 (P.L. 105-277). Restored function and aesthetics are the goals of any reconstructive surgery. However, current techniques of breast reconstructive surgery cannot restore lactation and normal sensation. Therefore, the main goal of breast reconstructive surgery is restoration of aesthetics to assist breast cancer survivors in regaining a high quality of life. Aesthetics refers to physical characteristics of the breasts, such as shape, symmetry, and ptosis.

Adequate measures of surgical outcome are important to protect patients’ health and well-being. Healthcare providers, the insurance industry, and the government also need objective measures to set up reasonable guidelines for care. The lack of a generally accepted quantitative method for assessing breast aesthetics limits the effective assessment of the outcomes after breast reconstructive surgery.

Currently, physicians, patients, or other observers report subjective assessments of breast aesthetics based on printed photographs, digital images, or directly viewing patients [5], [6], [7], [8], [9], [10], [11], [12], [13], [14]. However, these methods have been shown to have low intra- and inter-observer agreement. Quantitative, objective measures with high reliability are needed in order to investigate the relationships between patient and surgical variables and aesthetic outcomes.

The previous studies of photogrammetry to quantify breast aesthetics provide a strong foundation for our work [18], [20], [36], [37], [38], [39]. However, there are certain limitations that must be overcome through additional investigations. First, prior studies have only used only AP views. Important aesthetic properties, such as ptosis described below, may not be adequately visible in the AP view. Second, the objective photogrammetry measures proposed in the literature are focused on symmetry characteristics to the point that some other properties such as ptosis are not addressed. Third, since prior photogrammetry studies were concerned with breast conservation therapy, assumptions were made that are not met in reconstructive surgery. In particular, measures were calculated assuming that only one breast was surgically altered, whereas even in unilateral reconstruction procedures it is often necessary to modify the unaffected breast to achieve symmetry.

An important aesthetic property that has not been addressed by prior photogrammetry studies is ptosis. Ptosis of the breast is classified according to the relationship between the nipple and the inframammary fold, the crease beneath the breast. Unacceptable ptosis occurs when nipple and lower pole of the breast descend lower than the level of inframammary fold [15]. Regnault [16] defined four grades of ptosis. A patient has no ptosis when the nipple and most of the breast gland is located above the level of submammary fold (Grade 0). In first degree or minor ptosis, the nipple is at the level of submammary fold and above the lower contour of the breast (Grade 1). Second degree or moderate ptosis is when the nipple lies below the fold but above the lower contour (Grade 2). Third degree or major ptosis is when the nipple lies at the lower breast contour and most of the breast is below the fold (Grade 3). The ptosis scale with example photographs is described in Table 1 and Fig. 1.

In this study, we designed quantitative, objective measurements of breast ptosis based on ratios of distances between fiducial points manually identified in lateral and oblique views of clinical photographs. The new objective measures were compared to ratings on a subjective scale made by three experienced clinical observers. Intra- and inter-observer variability of the new objective measures and subjective ratings were investigated.