POST-BREAST CANCER LYMPHEDEMA: INCIDENCE INCREASES FROM 12 TO 30 TO 60 MONTHS

Abstract

Breast cancer survivors are at life-timerisk of developing lymphedema (LE).Quantification of LE has been problematic asthe criteria used to identify lymphedema usevarious methods to assess changes in thevolume of the affected limb. In part because ofdifficulties and variability in measurement anddiagnosis, the reported incidence of LE variesgreatly among women treated with surgery andradiation for breast cancer. The goal of thisresearch was to describe the trends for LEoccurrence over three points in time (12, 30,and 60 months) among breast cancer survivorsusing four diagnostic criteria based on threemeasurement techniques. Participants wereenrolled following diagnosis of breast cancerbut before surgery. Baseline limb volume andsymptom assessment data were obtained.Participants were followed every 3 months for12 months, then every 6 months thereafter fora total of 60 months. Limb volume changes(LVC) in both limbs were measured usingthree techniques: objectively by (a) circumferencesat 4 cm intervals and (b) perometryand subjectively by (c) symptom experiencevia interview. Four diagnostic criteria for LEmost often reported in the literature wereused: (i) 2 cm circumferential change; (ii) 200mL perometry LVC; (iii) 10% perometry LVC;and (iv) signs and symptoms (SS) report oflimb heaviness and swelling, either ‘now’ or‘in the past year’ (diagnostic criteria i-iiidefine increases/differences in limb volumefrom baseline and/or between the affected andnon-affected limb). Standard survival analysismethods were applied to identify when thecriteria corresponding to LE were met. Trendsin LE occurrence are reported for preliminaryanalysis of data from 236 participantscollected at 6-, 12-, 18-, 24-, 30-, and 60-months post-op. At 60 months post-treatment,LE incidence using the four criteria rangedfrom 43% to 94%, with 2 cm associated withthe highest frequency for lymphedemaoccurrence and SS the lowest. Sixty-monthtrends are compared to earlier trends at 12-and 30-months, per criterion. These preliminaryfindings provide additional evidence thatbreast cancer survivors are at risk fordeveloping LE beyond the first year followingtreatment. Cases of lymphedema continue toemerge through 60-months post-breast cancersurgery. This 60-month analysis supports theprevious 12- and 30-month analyses in findingthe 2 cm criteria to be the most liberal definitionof LE. The self-report of heaviness andswelling, along with 10% LVC, represent themost conservative definitions (41% and 45%,respectively). Furthermore, the variety ofcriteria used to identify LE, along with theabsence of baseline (pre-treatment) measurements,likely contribute to the wide range ofLE incidence rates reported in the literature.