How do you assess for lymphedema?

Assessment of Lymphedema

Lymphedema assessment begins with investigating self-reported symptoms of swelling, heaviness, and numbness, followed by physical examination including palpation for tissue changes and the Stemmer sign test, with circumferential measurements serving as the standard diagnostic method for confirmation. 1

Clinical History and Risk Factor Assessment

• Identify prior cancer treatment history, particularly lymph node dissection (axillary or sentinel node biopsy) and radiation therapy, as these are the primary risk factors for secondary lymphedema 1
• Document history of trauma, infection, or congenital abnormalities that may contribute to lymphatic dysfunction 1
• For breast cancer survivors specifically, assess for symptoms in the arm, breast, or chest wall on the affected side 1
• Note that lymphedema can develop immediately after treatment or up to 30 years later 2

Physical Examination Techniques

Stemmer Sign Test

• Perform the Stemmer sign: attempt to lift the skin fold at the base of the second toe or finger 1
• Inability to lift the skin fold compared to the contralateral limb indicates lymphedema 1
• Caution: Obesity can cause a false-positive Stemmer sign 1

Tissue Assessment

• Palpate the affected area for fibrosis, pitting edema, and overall tissue quality 2, 1
• For head and neck lymphedema, use the Modified Head and Neck External Lymphedema and Fibrosis assessment criteria 2, 1
• Distinguish lymphedema from other causes of edema by evaluating for unilaterality and lack of response to elevation or diuretics 1

Objective Measurement Methods

Circumferential Measurement (Primary Diagnostic Tool)

• Circumferential measurement is the standard method for diagnosing upper extremity lymphedema at Stage 1 or greater 2, 1
• Measure at nine standardized levels on the affected limb 3
• A calculated volume differential ≥200 mL between limbs helps confirm lymphedema 2
• If preoperative measures are available, a 5% or greater volume change from baseline above and below the elbow is diagnostic 1

Water Displacement Volumetry

• Use water displacement to diagnose lymphedema with volumetry >200 mL compared to the contralateral limb 2, 1
• A volume difference >10% interlimb difference is diagnostic 2, 1

Bioimpedance Analysis (BIA)

• BIA should be used to detect lymphatic transport impairments and diagnose subclinical and early-stage lymphedema (Stage 0 and 1) 2, 1
• L-Dex score >7.1 is diagnostic for breast cancer-related lymphedema when no preoperative assessment is available 2, 1
• L-Dex score >10 above preoperative baseline is diagnostic when baseline measures exist 2
• Important caveat: In moderate to late-stage lymphedema with fibrosis, BIA may show decreasing extracellular fluid even with increased tissue volume 2, 1

Diagnostic Questionnaires

• Utilize the Norman Questionnaire to assist in diagnosis of secondary upper quadrant lymphedema 2, 1
• Use the Morbidity Screening Tool as an additional validated assessment 2, 1

Advanced Imaging (When Diagnosis is Uncertain)

First-Line Imaging

• Ultrasound should be used as a diagnostic tool to identify tissue changes 2, 1
• Lymphoscintigraphy may be used to detect lymphatic system impairment when the diagnosis is uncertain 2, 1, 4

Additional Imaging Modalities

• MRI and CT may be used as diagnostic tools in complex cases 2, 1, 4
• Lymphography may be used to detect lymphatic system impairment in specialized settings 2, 1

Assessment Tools NOT Recommended for Diagnosis

• Perometry may be used for volume assessment but NOT as a diagnostic tool 2, 1
• Tissue Dielectric Constant may be used for assessment but NOT as a diagnostic tool 2, 1
• Tonometry is NOT recommended as a diagnostic tool 2, 1

Staging and Severity Assessment

• Use the International Society of Lymphology staging system to categorize lymphedema extent 2, 1
• Grade 1: 5-10% interlimb discrepancy 2
• Grade 3: >30% interlimb discrepancy 2
• A volume ratio of 1.04 may be indicative of upper extremity lymphedema 2

Referral Criteria

Patients with clinical symptoms or swelling suggestive of lymphedema should be referred to a therapist knowledgeable about lymphedema diagnosis and treatment, such as a physical therapist, occupational therapist, or lymphedema specialist 2, 5, 1

Common Pitfalls to Avoid

• Do not delay investigation of self-reported symptoms, as early diagnosis facilitates more effective intervention 1
• Regular examination is required even among patients without lymph node dissection 5
• Do not rely solely on visual inspection; objective measurements are essential for accurate diagnosis 1
• Be aware that obesity complicates diagnosis and may cause false-positive findings 1
• Remember that lymphedema can develop decades after cancer treatment, requiring long-term vigilance 2