Breast pain and MPS

Stimulated by Mandiroğlu et al 2021.[1]

MPS – myofascial pain syndrome
PM&R – physical medicine and rehabilitation
SF–MPQ – Short Form McGill Pain Questionnaire
FiRST – Fibromyalgia Rapid Screening Tool

key to acronyms

Referred pain from muscle has been an interest of mine since my earliest days in clinical medicine, and in particular my developing interest in sports and musculoskeletal medicine. Adopting filiform acupuncture needles whilst in military general practice, and mostly discarding the cutting hypodermic ones, led me to use the needles as probes to examine referred pain from muscle. Due to the high and tissue specific pressure applied by an acupuncture needle, the referred phenomena would often be much clearer to the patient than with palpation alone.

Where referred pain from muscle overlaps with pain from other tissues, the other tissues usually take priority in the differential diagnosis, and appropriately so, but the potential muscle source is often overlooked.

Breast pain is a good example. When a female patient presents with breast pain, the immediate thought is to assess the glandular tissue for mastitis, fibrocystic disease or malignancy, and rarely would somatic pain be considered.

This paper from Ankara investigates, for the first time, the frequency of MPS in women presenting to a general surgery outpatient department, and the results are quite interesting, so I thought I should share them here.

131 consecutive patients with breast pain in the last week were included provided that they did not meet any of the exclusion criteria:

• Known organic disease
• Previous breast surgery
• Irregular menstrual cycle
• Pregnant or breastfeeding

A breast pain or mastalgia score was measured using a previously developed modification of the short form McGill Pain Questionnaire (SF-MPQ).[2] They also used the Turkish version of the fibromyalgia rapid screening tool (FiRST).[3]

Four diagnostic categories were used:

• MPS
• Cyclical mastalgia
• Fibrocystic disease
• Mastitis

Patients were only included in the MPS category if they had active trigger points in pectoral muscles or latissimus dorsi, and did not fit into either of the other diagnostic categories.

35% of breast pain patients were diagnosed with MPS

Of the 131 patients, 46 (35%) were diagnosed with MPS, 34 (26%) with cyclical mastalgia, 21 (16%) with fibrocystic disease, 15 (11.5%) with mastitis, and the remaining 15 (11.5%) had mastalgia related to cancer, hormone replacement therapy or fibromyalgia.

The breast pain scores were highest on average in the mastitis group, similar in the MPS and fibrocystic disease groups and lowest in the cyclical mastalgia group. The majority of women with MPS presented with unilateral pain (97.8) in the upper quadrants of the breast (78.3%), and those with cyclical mastalgia mostly had bilateral pain (88.2%) in the lower quadrants (70.6%).

This cohort of 131 patients presenting with breast pain were screened for fibromyalgia using FiRST, which has a sensitivity of over 90%. They only found 4 cases, but 46 with MPS. The authors make a good point that the studies that have suggested fibromyalgia and mastalgia may be associated,[4,5] with each group having a significant overlap with the other, have not looked for MPS.

References

1          Mandiroğlu S, Yüksel UM, Ünsal Delialioğlu S, et al. Is it mastalgia or myofascial pain? A clinical confusion. Arch Rheumatol 2021;36:114–9. doi:10.46497/ArchRheumatol.2021.8255

2          Khan SA, Apkarian AV. The characteristics of cyclical and non-cyclical mastalgia: a prospective study using a modified McGill Pain Questionnaire. Breast Cancer Res Treat 2002;75:147–57. doi:10.1023/a:1019685829799

3          Perrot S, Bouhassira D, Fermanian J, et al. Development and validation of the Fibromyalgia Rapid Screening Tool (FiRST). Pain 2010;150:250–6. doi:10.1016/j.pain.2010.03.034

4          Genc V, Genc A, Ustuner E, et al. Is there an association between mastalgia and fibromyalgia? Comparing prevalence and symptom severity. Breast Edinb Scotl 2011;20:314–8. doi:10.1016/j.breast.2011.01.016

5          Sen M, Kilic MO, Cemeroglu O, et al. Can mastalgia be another somatic symptom in fibromyalgia syndrome? Clin Sao Paulo Braz 2015;70:733–7. doi:10.6061/clinics/2015(11)03

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Declaration of interests MC