Prospective study of shoulder strength, shoulder range of motion, and lymphedema in breast cancer patients from pre-surgery to 5 years after ALND or SLNB

Roser Belmonte, Monique Messaggi-Sartor, Montse Ferrer, Angels Pont & Ferran Escalada. Supportive Care in Cancer. April, 2018

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Prospective study of shoulder strength, shoulder range of motion, and lymphedema in breast cancer patients from pre-surgery to 5 years after ALND or SLNB

Roser Belmonte, Monique Messaggi-Sartor, Montse Ferrer, Angels Pont & Ferran Escalada. Supportive Care in Cancer. April, 2018

Objective

Determine the changes in shoulder strength, shoulder range of motion, and arm volume in breast cancer patients treated with sentinel lymph node biopsy (SLNB) or axillary lymph node dissection (ALND)

Method

Sixty-eight SLNB and 44 ALND patients were followed up from pre-surgery to 5 years after surgery. Primary outcomes were the differences between affected and non-affected sides for the following: shoulder strength measured by dynamometry, shoulder range of motion measured by goniometry, and lymphedema measured by volume. As a secondary outcome, health-related quality of life (HRQL) was assessed by the Short Form-36 Health Survey (SF-36) and the Functional Assessment of Cancer Therapy for breast cancer (FACT-B+4) questionnaires. Changes over time were tested for SLNB and ALND using univariate repeated measures analysis of variance. Generalized estimating equation models were constructed to assess the effect of SLNB and ALND over time. Results After 5 years, the ALND group had significant loss of strength for internal rotators (1.39 kg, p=0.001) and significant arm volume increase (132.45mL,p=0.031). The ALND group had a greater number of patients with clinically relevant internal rotator strength loss (38.7 vs. 13.6%, p=0.012) and a greater number of lymphedema requiring treatment (33.3 vs. 3.4%, p<0.001) than the SLNB group. A loss of strength for shoulder external rotators, shoulder range of motion, and HRQL in physical and arm domains persisted at 5 years in both SLNB and ALND groups.

Conclusion

These results could help understand and plan the prevention, needs, and long-term care of breast cancer patients.

Main findings

  • Knowing which muscles or groups of muscles are responsible for the loss of strength could help more precise identification of the cause and possibly preventing it. Moreover, this information could help develop strategies for more efficient rehabilitation treatments.
  • Clinical assessment and patient self-completion of HRQL questionnaires took place in the rehabilitation setting of the breast cancer unit, at baseline (pre-surgery) and at the first and fifth year post-surgery.
  • The shoulder strength of both arms was measured in kilograms by a hand-held dynamometer assessing external rotators, internal rotators, abductors, and the serratus anterior muscles.
  • The shoulder range of motion of both arms was measured by a goniometer in degrees (flexion, abduction, external rotation, and internal rotation).
  • The presence of lymphoedema was assessed pre surgery and at the follow up appointments. The patients were asked if they experienced pain, heaviness, tightness, hardness, or any other symptoms.
  • The circumference of both upper limbs were measured at seven pre-established points and the volume was calculated via the truncated cone formula.
  • HRQL questionnaires were self-administered in the waiting room which included the Short Form-36 Health Survey (SF-36) and the FACT-B+4 questionnaire.
  • The analysis was performed with the groups treated by SLNB and ALND pre-surgery, at 1, and at 5 years of follow-up. The primary outcomes were the difference between affected and unaffected sides for the following: shoulder strength, shoulder range of motion, and arm volume.
  • Lymphoedema was considered clinically relevant when it required treatment and 2cm or greater in circumference.
  • Among patients undergoing SLNB, the unaffected side showed after 1 year significant loss of serratus anterior muscle strength from pre-surgery and an almost significant increase in external rotators strength after 5 years.
  • The ALND group showed losses in the strength of the affected side for external rotators 1 year after surgery and for internal rotators at 1 and 5 years after surgery. The unaffected side of the ALND group showed an increase of external rotator strength from pre-surgery to 5 years after.
  • The differences between affected and unaffected sides in ALND group showed a significant loss of strength for internal rotators after 1 (1.68 kg, p<0.001) and 5 years (1.39 kg, p=0.001). The mean change of differences between affected and unaffected sides at 5 years showed a significantly greater loss for internal rotator strength in the ALND group than the SLNB group.
  • The ALND group only differed from SLNB for internal rotators’ strength 1 year after surgery.
  • The affected side of the ALND group lost shoulder range of motion comparing pre-surgery with both 1 and 5 years after.
  • From pre-surgery to 5 years of follow-up, there was a persistent loss of shoulder strength of the affected side for the internal rotators in the ALND group, which also presented more cases of upper limb lymphedema than the SLNB group.
  • From pre-surgery to 5 years of follow-up, both SLNB and ALND groups showed impairment in the Physical and Arm components of HRQL scales, while Emotional components improved.
  • There was no significant differences when comparing elbow or grip strength of the affected side.
  • The most important shoulder internal rotator muscles are subscapularis, pectoralis major, teres major, and latissimus dorsi, and these muscles are part of the anatomy of the axillary fossa. Both ALND and radiotherapy affect the axillary fossa and pectoral area and may cause damage to its structures. This could explain the internal rotator loss of strength observed in the present study.
  • Shoulder abduction and scaption mainly depends on the deltoid and supraspinatus, muscles that are not part of the axillary fossa. Exploring the shoulder abductors is not enough to detect all deficits in shoulder strength after breast cancer surgery, and neither is the measure of elbow or grip strength.
  • ALND group had 33.3% of lymphedema requiring treatment while the SLNB group only had 3.4%.
  • Both SLNB and ALND groups showed impairment in the Physical and Arm components of HRQL scales, while emotional components improved over time from pre surgery to 5 years of follow-up. At 5 years, the improvement in the Emotional component was only significant for the SLNB group.
  • This study had some limitations. The number of patients lost during follow-up was close to one third in each group.
  • The present study was carried out in a rehabilitation setting where the shoulder range of motion was systematically included in the prevention protocol and treated when necessary, and this must have interfered by improving the results for this variable.
  • More research is warranted to know which shoulder muscles lose strength in these patients.