What is the evaluation and management plan for a perimenopausal female with left breast itching and left axillary odor after showering and applying deodorant?

Evaluation and Management of Perimenopausal Female with Left Breast Itching and Left Axillary Odor

This patient requires urgent bilateral diagnostic mammography with or without ultrasound to rule out Paget's disease of the breast, as unilateral breast itching is a red flag symptom that warrants immediate malignancy evaluation, regardless of the concurrent axillary odor complaint. 1

Initial Diagnostic Workup

Breast imaging must be performed first, as the combination of unilateral breast itching with ipsilateral axillary symptoms raises concern for serious pathology:

• Obtain bilateral diagnostic mammography with or without ultrasound as the initial imaging study 1
• The itching symptom specifically raises suspicion for Paget's disease, which presents with eczema of the nipple or areola, bleeding, ulceration, and itching of the nipple 1
• Paget's disease is frequently occult on mammography, so a negative mammogram does not exclude the diagnosis 1

Skin Biopsy Protocol Based on Imaging Results

If imaging shows BI-RADS category 1-3 (negative, benign, or probably benign):

• Perform punch biopsy of the affected breast skin or nipple biopsy 1
• Do not delay biopsy based on normal imaging, as Paget's disease can be mammographically occult 1
• If biopsy results are benign, reassess clinical-pathologic correlation and consider breast MRI, repeat biopsy, and consultation with a breast specialist 1

If imaging shows BI-RADS category 4-5 (suspicious or highly suggestive of malignancy):

• Perform core needle biopsy with or without punch biopsy as the preferred option 1
• If core biopsy is benign but clinical suspicion remains, proceed with punch biopsy of the skin 1

Axillary Evaluation

After addressing the breast concern, evaluate the axillary symptoms:

• Perform axillary ultrasound to assess for lymphadenopathy, as this is the primary modality for evaluating axillary nodes 2, 3
• Look for morphologically abnormal lymph nodes with abnormal cortical thickness, loss of fatty hilum, or abnormal vascularity 2
• If suspicious nodes are identified on ultrasound, perform ultrasound-guided core needle biopsy for definitive diagnosis 2, 3

Differential Diagnosis for Axillary Odor

If malignancy is excluded, the axillary odor is likely benign and related to:

• Bacterial decomposition of apocrine secretions by aerobic coryneforms (particularly Corynebacterium species) and Anaerococcus species in the axilla 4, 5
• This is a common phenomenon that can be exacerbated by deodorant use in some individuals 6, 7

Management of Benign Axillary Odor (Only After Malignancy Excluded)

Conservative measures:

• Improve hygiene practices and consider changing deodorant products 7
• Topical antimicrobial agents targeting axillary bacteria 4, 5

If conservative measures fail:

• Botulinum toxin A injection (100 U) into the affected axilla, which significantly reduces odor intensity and unpleasantness 6
• This is the best non-surgical treatment option based on network meta-analysis 8

Critical Pitfalls to Avoid

• Never dismiss unilateral breast itching as a benign dermatologic condition without imaging and potential biopsy, as Paget's disease diagnosis is often delayed due to confusion with benign conditions 1
• Do not attribute axillary symptoms to simple body odor until breast malignancy with axillary metastases has been excluded 1, 2
• Do not rely on clinical breast examination alone, as sensitivity and specificity are limited for detecting both breast cancer and axillary disease 3
• Do not allow antibiotics to delay diagnostic evaluation if given empirically for suspected infection 1