Evaluation of a solitary breast mass in a woman less than 35 years old should begin with ultrasound; if ultrasound demonstrates a complex cyst or solid mass, a fine needle aspiration is needed to obtain a diagnosis.
For an ultrasound showing a solid mass or complex cyst, an ultrasound-guided core needle biopsy is another viable alternative to a fine needle aspiration. In comparison, fine needle aspiration (FNA) is more user-dependent; however, it is an accurate technique when conducted and interpreted by experienced providers. FNA also may yield insufficient or inconclusive results, requiring follow-up core needle or surgical biopsy. FNA is preferred when there is a low pre-test probability of cancer (such as in this patient without any identifiable risk factors).
Salzman et al. discuss the approach and work-up of a patient with a palpable breast mass. Mammography is the recommended evaluation of a palpable breast mass in women older than 30 or in patients younger than 30 who are at high risk for breast cancer. Ultrasound is the preferred imaging modality in patients younger than 30. If fine needle aspiration, clinical examination, and imaging all suggest a benign process, there is a greater than 99% chance that the mass is benign.
Brancato et al. discuss needle biopsy and compare core needle biopsy (CNB) versus FNA for diagnosis of breast lesions that are visible on ultrasound. They found that CNB is more sensitive but less specific in comparison to FNA. Although CNB is more reliable overall, FNA still has a predominant role as a first-line test. When FNA results are inadequate or inconclusive, diagnosis can be resolved with repeat sampling by CNB.
Figure A is an ultrasound image showing a complex breast cyst; note the coexistence of solid and cystic components to the mass. Illustration A summarizes the initial work-up required for a patient with a palpable breast mass. Illustration B shows an algorithm by Klein in her article in American Family Physician for the evaluation of a palpable breast mass.
Answer 1: A complex cyst on breast ultrasound requires continued work-up with fine needle aspiration in order to rule out malignancy and other pathologies. If the ultrasound had shown a simple cyst, no further work-up would be required.
Answer 2: Correct treatment for a simple cyst (not a complex cyst as in this patient) detected on ultrasound is to aspirate the lesion and have the patient return in 4-6 weeks for re-examination.
Answer 3: Ultrasound is a more effective imaging modality in women less than 35 years of age, as the dense breast tissue of younger women leads to poor image quality on mammography. However, mammography may be attempted, but, given the ultrasound results in this case, it should be combined with a biopsy (CNB or FNA) as well.
Answer 5: Excisional biopsy is reserved for lesions that cannot be definitely diagnosed by imaging and biopsy techniques or for patients that request removal of a benign mass for comfort or cosmetic reasons.
Salzman B, Fleegle S, Tully AS. Common breast problems. Am Fam Physician. 2012 Aug 15;86(4):343-9.
PMID:22963023 (Link to Abstract)
Brancato B, Crocetti E, Bianchi S, Catarzi S, Risso GG, Bulgaresi P, Piscioli F, Scialpi M, Ciatto S, Houssami N. Accuracy of needle biopsy of breast lesions visible on ultrasound: audit of fine needle versus core needle biopsy in 3233 consecutive samplings with ascertained outcomes. Breast. 2012 Aug;21(4):449-54.
PMID:22088803 (Link to Abstract)
Klein S. Evaluation of palpable breast masses. Am Fam Physician. 2005 May 1;71(9):1731-8.
PMID:15887452 (Link to Abstract)