US Evaluation of Axillary Lymph Nodes

Transcription

1 US Evaluation of Axillary Lymph Nodes Jose M. Net, MD Tarun M. Mirpuri, MD Michael J. Plaza, MD Cristina A. Escobar, MD Elizabeth E. Whittington, MD Fernando Collado-Mesa, MD Monica M. Yepes, MD All authors have disclosed no relevant relationships. Address correspondence to J.M.N., Breast Imaging Section, Department of Radiology, University of Miami Sylvester Comprehensive Cancer Care Center, 1475 NW 12 th Ave, Miami, FL (

2 Introduction Axillary adenopathy is frequently encountered during breast cancer screening and in the diagnostic work-up of symptomatic patients. A broad spectrum of disease processes may result in axillary adenopathy. Knowledge of normal nodal morphologic characteristics and distribution and of the various possible causes of lymph node enlargement, combined with patient-specific clinical information, aids in accurate diagnosis. After viewing this presentation, readers should be able to: Describe the imaging appearance of the normal nodal anatomy Identify abnormal nodes List differential causes of unilateral versus bilateral adenopathy Discuss possible reasons for increased nodal density and nodal calcification Describe possible causes of a palpable axillary mass or masses, including processes that mimic axillary adenopathy

3 Key Concepts Ultrasonography (US) is the preferred modality for assessing axillary lymph nodes Thickness and uniformity of the nodal cortex are the most important criteria for distinguishing normal lymph nodes from abnormal ones Cortical thickness should be less than or equal to 3 mm; the cortical margin should be smooth, and the fatty hilum should be intact If an abnormal axillary node is found, the ipsilateral breast and contralateral axilla should be closely examined and the patient s medical history reviewed If adenopathy is unilateral: breast cancer, metastasis, and infectious cellulitis should be included in the differential diagnosis Ipsilateral breast cancer is the most common cause of unilateral axillary adenopathy If adenopathy is bilateral: consider the possibility of a systemic process Lymphoma, human immunodeficiency virus (HIV), autoimmune or connective tissue disorder Various mimics of axillary adenopathy may prompt imaging work-up and should be included in the differential diagnosis of any palpable axillary abnormality Sebaceous cyst, accessory breast tissue, lipoma, and seroma are possible mimics In a patient with a known malignancy, normal nodal morphologic features do not necessarily permit the exclusion of malignancy from the differential diagnosis; a sentinel node biopsy may be needed for that purpose

4 Axillary Anatomy Axillary lymph nodes are described according to their location relative to the pectoralis minor muscle: Level I nodes are lateral to the muscle Level II nodes are deep to the muscle Level III nodes are medial to the muscle Nodes at level I are better depicted at US than are those at level II or III. (Courtesy of Albert Fung, MScBMC, Department of Surgical Oncology, University of Toronto Princess Margaret Hospital, Toronto, Ontario, Canada.) Level III Level I Level II Axial T1-weighted fat-saturated magnetic resonance (MR) image obtained after the injection of a gadolinium-based contrast material (left) and three-dimensional illustration (above) show the zonal anatomy of axillary lymph nodes.

5 Normal or Pathologic? Criteria for Assessing Axillary Lymph Nodes Observation Normal Abnormal Shape Reniform Rounded Cortical thickness 3 mm, smooth cortex with uniform thickness >3 mm, eccentric thickening of cortex Fatty hilum Present Displaced or absent Cortical echotexture Homogeneous Hypoechoic; may be heterogeneous with calcifications Color Doppler findings Blood supplied via a single vessel entering at the hilum Blood supplied by multiple peripheral vessels Margins Smooth Angulated, irregular Appearance relative to that of adjacent lymph nodes Similar Different

6 Differentiation at US: Normal Lymph Node vs Lymphadenopathy Normal shape: reniform Abnormal shape: rounded Normal cortical thickness: 3 mm Abnormal cortical thickness: >3 mm (continues)

7 Differentiation at US: Normal Lymph Node vs Lymphadenopathy Normal flow at Doppler imaging: blood supplied by a vessel entering the hilum Abnormal flow at Doppler imaging: blood supplied only by peripheral vessels Normal appearance of fatty hilum Fatty hilum displaced or absent

8 Unilateral Axillary Adenopathy: Differential Diagnosis Benign causes Regional infection (eg, cat-scratch disease, toxoplasmosis, tuberculosis, ipsilateral upper-extremity cellulitis, mastitis) Dermatopathic lymphadenopathy Silicone-induced granulomatous lymphadenitis Malignant causes Metastasis from primary breast cancer Metastasis from nonbreast primary malignancy (eg, melanoma; cancer of the thyroid, lung, gastrointestinal tract, pancreas, or ovary) Lymphoma occasionally occurs unilaterally

9 Unilateral Axillary Adenopathy: Metastasis from Primary Breast Cancer Right mediolateral oblique (MLO) and magnified views from screening mammography in a 47-year-old woman show a rounded, dense axillary node with irregular margins, but no obvious breast mass. Transverse US image shows a round, hypoechoic axillary node with replaced fatty hilum. US-guided core biopsy of the lymph node yielded metastatic mammary carcinoma.

10 Unilateral Axillary Adenopathy: Metastasis from Primary Breast Cancer MLO view obtained at screening mammography in a 50-year-old asymptomatic woman shows a right breast mass and ipsilateral axillary adenopathy. Gray-scale US image obtained in the same patient for further characterization of the abnormal nodes shows nodal rounding with eccentric cortical thickening and hilar encroachment.

11 Unilateral Axillary Adenopathy: Metastasis from Occult Primary Breast Cancer Left MLO mammogram in a 79-year-old woman with a palpable left axillary mass and history of a right mastectomy shows isolated axillary adenopathy (arrow) with no definite breast mass. US image shows a hypoechoic lymph node with replacement of the fatty hilum. No evidence of a primary breast malignancy was seen at US. MR image of the left breast and axilla shows an indistinct breast mass with surrounding clumped nonmass enhancement and a rounded axillary lymph node. Biopsy yielded invasive ductal carcinoma with metastasis to the ipsilateral axilla.

12 Axillary Metastases from Primary Breast Cancer: Summary

13 Metastases from Nonbreast Primary Malignancies: Melanoma Axillary mass in a 48-yearold woman with a history of melanoma. US image shows an enlarged, hypoechoic lymph node with loss of the normal fatty hilum, an appearance that is suggestive of malignancy. Metastasis from melanoma was subsequently found at biopsy.

14 Infectious Lymphadenitis: Cat-Scratch Disease Left mammogram and left axillary US images, obtained in a 46-year-old woman with acute symptoms like those of influenza, show markedly enlarged axillary lymph nodes, with cortical thickening and displacement of the fatty hilum. (Case continues.)

15 Infectious Lymphadenitis: Cat-Scratch Disease Photomicrographs (left: original magnification, 20; right: original magnification, 10; both, hematoxylin-eosin stain) of histologic slices obtained at surgical biopsy of a lymph node show necrotizing granulomatous lymphadenitis. These findings are characteristic of cat-scratch disease.

16 Dermatopathic Lymphadenopathy Mammogram obtained in a 57-yearold woman with palpable left axillary nodes and a history of multiple furuncles on her upper extremities shows an enlarged node (arrow) but no suspicious breast mass or calcifications. (Case continues on next slide.) Axillary US image shows a lymph node with a thickened cortex (red arrow) relative to that of a normal adjacent node (black arrow).

17 Dermatopathic Lymphadenopathy Photomicrograph (original magnification, 20; hematoxylin-eosin stain) of a lymph node biopsy specimen shows features consistent with a diagnosis of dermatopathic lymphadenopathy, including nodular expansion of the interfollicular region with histiocytes containing melanin (black arrows), eosinophils, and plasma cells. Prominent postcapillary venules (white arrow) and follicular hyperplasia also are seen.

18 Granulomatous Lymphadenitis Noninfectious subtypes: Sarcoidosis lymphadenitis Sarcoidlike lymphadenitis (eg, in Hodgkin and non-hodgkin lymphomas) Berylliosis Infectious and suppurative subtypes: Tularemic lymphadenitis Cat-scratch disease Yersiniosis Venereal lymphogranuloma Fungal lymphadenitis Infectious and nonsuppurative subtypes: Tuberculous lymphadenitis Atypical mycobacterial infection BCG lymphadenitis Toxoplasmic lymphadenitis (Piringer-Kuchinka lymphadenopathy) Syphilitic lymphadenitis Brucellosis lymphadenitis Fungal lymphadenitis

19 Granulomatous Lymphadenitis MLO view obtained at screening mammography shows a markedly enlarged left axillary lymph node in a 52-year-old asymptomatic woman with a history of negative findings at left breast biopsy. US image (left) shows an enlarged, heterogeneous lymph node in the left axilla. Photomicrograph (below; original magnification, 10; hematoxylineosin stain) of a specimen from US-guided core biopsy shows findings indicative of granulomatous lymphadenitis. The cause was not determined.

20 Histiocytic Reaction Left MLO and magnified views from screening mammography in a 52- year-old asymptomatic woman show an enlarged calcified axillary lymph node (arrows, left) and an ovoid circumscribed mass in the upper breast quadrants (far left). The mass had a cystic appearance at US. (The dermal calcifications are unrelated.) US image at right shows enlarged axillary lymph nodes with a thickened cortex. Pathologic analysis of a biopsy specimen showed the presence of reactive histiocytosis.

21 Bilateral Axillary Adenopathy: Differential Diagnosis Benign causes HIV Autoimmune and connective tissue diseases such as rheumatoid arthritis, scleroderma, dermatomyositis, systemic lupus erythematosus (SLE), and psoriasis Lymphoid hyperplasia due to infectious-inflammatory conditions such as infectious mononucleosis and cat-scratch disease Granulomatous lymphadenitis (sarcoidosis, tuberculosis) Malignant causes Lymphoma Leukemia HIV-associated malignancies (eg, Kaposi sarcoma) Metastases from lung cancer, melanoma, and (uncommonly) breast cancer

22 Bilateral Axillary Adenopathy: Lymphoma Bilateral enlarged lymph nodes are seen with no evidence of breast cancer at screening mammography (left) in a 67-year-old asymptomatic woman. US images (right) show nodal enlargement and cortical thickening. (Case continues.)

23 Bilateral Axillary Adenopathy: Lymphoma Photomicrographs (left: original magnification, 4; right: original magnification, 50; both, hematoxylin-eosin stain) of specimens from US-guided core biopsy of a left axillary lymph node show non-hodgkin lymphoma of the mantle cell type.

24 Bilateral Axillary Adenopathy: Leukemia Bilateral rounded and markedly enlarged axillary lymph nodes were seen on screening mammograms (left) obtained in a 68-year-old woman with recently diagnosed chronic lymphocytic leukemia. Axial CT image shows rounded axillary nodes (arrows, right).

25 Bilateral Axillary Adenopathy Due to HIV Infection MLO mammograms obtained in an asymptomatic 41-year-old woman with known HIV infection show bilateral enlarged axillary nodes. US images show enlarged axillary lymph nodes with loss of normal fatty hilum. USguided core biopsy yielded evidence of reactive lymphoid hyperplasia.

26 Bilateral Axillary Adenopathy: Toxoplasmic Lymphadenitis US images obtained in a 40-year-old man with a history of lymphoma and with newly palpable bilateral axillary lymph nodes show bilateral cortical thickening. Toxoplasmic lymphadenitis was diagnosed at USguided core biopsy and confirmed with serologic testing.

27 Dense and/or Calcified Axillary Adenopathy: BCG Adenitis Left MLO mammogram (far left) shows bulky, enlarged left axillary lymph nodes. Magnified view (near left) shows coarse calcifications within a node.

28 Dense and/or Calcified Axillary Adenopathy: Treated Lymphoma Comparison of left and right MLO views (above) obtained at screening mammography in a 53-year-old woman with a history of radiation therapy for lymphoma shows coarse rim- or eggshell-like calcifications in lymph nodes in the left axilla, findings most clearly seen on the magnified view (arrow, above right). Axillary US image shows a rounded, partly obscured hypoechoic mass (arrow, right) with a posterior shadow.

29 Dense and/or Calcified Axillary Adenopathy: Sarcoidosis MLO and magnified mammographic views show enlarged axillary lymph nodes with calcifications (arrows, left and center). Axial CT image (right) shows enlarged mediastinal and axillary lymph nodes.

30 Dense and/or Calcified Axillary Adenopathy: Gold Deposits Magnified views from screening mammography in a 68-year-old woman with a history of long-standing rheumatoid arthritis show high-density threadlike opacities indicative of gold deposition (left) and calcium deposits within axillary lymph nodes (arrow, right).

31 Dense and/or Calcified Axillary Adenopathy: Silicone Deposits Mammograms (left, center) obtained in a 64-year-old woman with severe bilateral breast pain and severely deformed breasts due to previous silicone implants and silicone injections show an enlarged axillary lymph node (arrow, center) with dense cortical deposits resembling calcium particles. Axillary US image (right) shows an enlarged lymph node with a snowstorm-like internal echotexture. (Case continues.)

32 Dense and/or Calcified Axillary Adenopathy: Silicone Deposits Photomicrographs (left: original magnification, 10; right, original magnification, 20; both, hematoxylin-eosin stain) of axillary lymph node biopsy specimens show granulomas and multinucleated giant cells, findings indicative of a foreign body inflammatory reaction. Multiple droplets of birefringent material embedded within the lymph node tissue were found to represent silicone deposits.

33 Other Palpable Axillary Masses: Inflamed Sebaceous Cyst Axillary US images obtained for evaluation of a rapidly growing palpable mass in the left axilla of a 47-year-old woman show an ovoid hypoechoic mass with mildly heterogeneous echotexture (arrow, left) and an adjacent rounded lymph node with a thickened cortex (arrow, right). (Case continues.)

34 Other Palpable Axillary Masses: Inflamed Sebaceous Cyst Photomicrograph (original magnification, 50; Papanicolaou stain) of a US-guided biopsy specimen of the hypoechoic mass with heterogeneous echotexture shows benign squamous epithelial cells and inflammatory cells, findings indicative of an inflamed sebaceous cyst.

35 Other Palpable Axillary Masses: Lipoma Mammogram obtained for evaluation of a palpable abnormality in the right axilla of a 43-year-old woman shows the inferior margin of a lipoma pseudocapsule (arrow, left) at the site of the Beekley triangle. Axillary US image (above) shows a solid mass with echogenicity similar to that of the fatty breast parenchyma. (Case continues.)

36 Other Palpable Axillary Masses: Lipoma Photomicrograph (original magnification, 20; hematoxylin-eosin stain) of a tissue specimen obtained at biopsy of the axillary mass shows adipose tissue with hemorrhage.

37 Other Palpable Axillary Masses: Seroma US image (above) shows a large fluid collection with a heterogeneous echotexture in the right axillary tail in a 72- year-old woman with a history of right mastectomy, breast reconstruction with a transverse rectus abdominis myocutaneous (TRAM) flap, and axillary dissection for breast cancer. Axial short inversion time inversion-recovery (STIR) MR images show hyperintense signal in the collection (top right) with no associated enhancement on the subtraction image obtained after injection of a gadoliniumbased contrast material (bottom right).

38 Management of Axillary Lymphadenopathy Detected on Screening Mammograms Unilateral axillary lymphadenopathy with no suspicious breast findings BIRADS 0:Bilateral axillary US should be performed to confirm findings are unilateral/asymmetric If no known infectious or inflammatory source present (i.e. mastitis, breast abscess, cat scratch fever), then BIRADS 4, FNA/Biopsy; If proven metastatic disease from breast primary, consider MRI to identify occult breast primary. If a benign cause can be elucidated, BIRADS 3, recommend 6 month follow-up to monitor involution according to etiology.

39 Management of Axillary Lymphadenopathy Detected on Screening Mammograms Bilateral axillary lymphadenopathy with no suspicious breast findings Correlate with patient history and clinical exam. If underlying infectious/ inflammatory condition (i.e. sarcoid, SLE, HIV), then BIRADS 2, Benign If known lymphoma then BIRADS assessment should be based on breast findings If no benign cause can be elucidated, BIRADS 4, consider biopsy to establish etiology. If lymphoma is considered, retrieve core samples in saline for cytometric flow work-up

40 Summary Findings of axillary lymphadenopathy at mammography or physical examination should be further evaluated with US Lymph node morphologic features are the most important factor for distinguishing between normal and abnormal nodes Normal lymph nodes have a smooth and uniform cortex with a thickness of up to 3 mm and with preservation of the fatty hilum Cortical thickness of more than 3 mm, eccentric cortical thickening, and displacement or replacement of the fatty hilum are indicative of an abnormal process If nodal abnormality is identified, the contralateral axillary nodes also should be assessed If adenopathy is unilateral, a thorough search should be performed for ipsilateral primary breast cancer at mammography and US, with MR imaging performed if necessary If adenopathy is bilateral, the imaging findings should be compared with the clinical history Various benign and malignant processes may lead to axillary lymphadenopathy If abnormal nodes are seen, the patient s medical history should be reviewed for pertinent information; clinical correlation is essential Processes that may mimic axillary adenopathy should be included in the differential diagnosis of any palpable axillary abnormality and should prompt a thorough imaging evaluation Sebaceous cyst, accessory breast tissue, and lipoma are commonly encountered Biopsy is often needed before the presence of a metastasis from underlying primary breast cancer or a primary nonbreast malignancy can be ruled out A normal appearance of the axillary lymph nodes is an insufficient basis for exclusion of malignancy from the differential diagnosis

41 Suggested Readings American College of Radiology. ACR BI-RADS atlas. 5 th ed. Reston, VA: ACR, American College of Radiology. Mammography Quality Standards Act (MQSA): frequently asked questions. /MammoFAQ.pdf. Asano S. Granulomatous lymphadenitis. J Clin Exp Hematop 2012;52(1):1 16. Bedi DG, Krishnamurthy R, Krishnamurthy S, et al. Cortical morphologic features of axillary lymph nodes as a predictor of metastasis in breast cancer: in vitro sonographic study. AJR Am J Roentgenol 2008; 191(3): Buchanan CL, Morris EA, Dorn PL, et al. Utility of breast magnetic resonance imaging in patients with occult primary breast cancer. Ann Surg Oncol 2005;12: Cao MM, Hoyt AC, Bassett LW. Mammographic signs of systemic disease. RadioGraphics 2011; 31: Carithers HA. Cat-scratch disease: an overview based on a study of 1,200 patients. Am J Dis Child 1985;139: Halsted WS. The results of radical operations for the cure of carcinoma of the breast. Part I. Ann Surg 1907;46(1):1 19. Kim EY, Ko EY, Han BK, et al. Sonography of axillary masses: what should be considered other than the lymph nodes? J Ultrasound Med 2009;28: Koehler JE, Duncan LM. Case records of the Massachusetts General Hospital. Case : A 56-year-old man with fever and axillary lymphadenopathy. N Engl J Med 2005; 353: Krementz ET, Cerise EJ, Cjaraveilla JM, Morgan LK. Metastases of undetermined source. CA 1977; 27: (continues)

42 Suggested Readings Monaco SE, Khalbuss WE, Pantanowitz L. Benign non-infectious causes of lymphadenopathy: a review of cytomorphology and differential diagnosis. Diagn Cytopathol 2012;40(10): doi: /dc Epub 2012 Feb 20. Moriarty RA, Margileth AM. Cat-scratch disease. Infect Dis Clin North Am 1987;1: Noguchi M, Katev N, Miyazaki I. Diagnosis of axillary lymph node metastases in patients with breast cancer. Breast Cancer Res Treat 1996;40: Patel T, Given-Wilson RM, Thomas V. The clinical importance of axillary lymphadenopathy detected on screening mammography: revisited. Clin Radiol 2005;60(1): Solomon SB, Gatewood OM, Brem RF. HIV infection: analysis of mammographic findings. Breast J 1999;5: Westbrook KC, Ballaser HS. Breast carcinoma in axillary lymph nodes as an indicator of breast cancer. Surg Gynecol Obstet 1962; 114:5 8.