Abstract
When a patient presented with ipsilateral lymphedema of the limb, an excisional biopsy of the left inguinal lymph node showed extensive smooth muscle and vascular proliferation replacing most of the lymph node.
Angiomyomatous hamartoma (AMH) of the lymph node is an extremely uncommon vascular disorder of unknown etiology, first described by Chan and colleagues in 1992.1–3 Angiomyomatous hamartoma particularly involves inguinal and femoral lymph nodes, with few cases reported in the cervical, popliteal, and submandibular lymph nodes.1 Angiomyomatous hamartoma can occasionally be associated with edema of the ipsilateral limb. To the authors’ knowledge, to date only 18 cases of AMH have been reported.4
CASE PRESENTATION
A 40-year-old white man started to have a left inguinal and scrotal pain along with left thigh swelling at age 22 while serving in the U.S. Army. A left hydrocelectomy was performed overseas; however, the patient’s symptoms persisted. He was evaluated in the U.S. at age 36, and the physical examination revealed a left medial thigh nonpitting edema, an enlarged left inguinal lymph node, bilateral axillary lymphadenopathy, and hepatosplenomegaly. A complete blood count, basic metabolic panel, liver function tests, hepatitis workup, autoimmune profile, iron studies, alphafetoprotein, and ceruloplasmin and copper levels were within normal limits.
An abdominal Doppler ultra-sound did not show any evidence of portal hypertension. A thoraco-abdomino-pelvic computed tomography (CT) scan showed bilateral axillary, subcarinal (Figure 1), mesenteric and retroperitoneal (Figure 2), and left inguinal (Figure 3) lymphadenopathy. Excisional biopsy of a 3.5 x 2.5 x 1.5 cm left inguinal lymph node was performed, and histopathology showed extensive smooth muscle and vascular proliferation replacing most of the lymph node (Figure 4), a finding consistent with AMH. A trichrome staining (Figure 5) and immunohistochemical study for smooth muscle actin (Figure 6) were performed and supported the diagnosis. Due to persistent pain in the scrotal area, the patient underwent a left spermatic cord denervation.
Figure 1.
Contrast Chest CT Showing Enlarged Subcarinal Node (Red Arrow)
Abbreviation: CT, computed tomography.
Figure 2.
Abdomen and Pelvis CT Axial Section Showing Enlarged Mesenteric (Red Arrow) and Retroperitoneal Periaortic Lymph Nodes (Blue Arrow)
Abbreviation: CT, computed tomography.
Figure 3.
Contrast Pelvis CT Axial Section Showing Left Inguinal Node (Red Arrow)
Figure 4.
High-Power View of Lymph Node Parenchyma With Blood Vessels and Fibromuscular Stroma, Hematoxylin-Eosin, Original Magnification x40
Figure 5.
Trichrome Stain, Original Magnification x100
Figure 6.
Immunohistochemical Stain for Smooth Muscle Actin (SMA), Original Magnification x100
Currently, the patient has persistent left thigh swelling. His condition remains stable with a regular follow-up CT scan showing unchanged lymphadenopathy.
DISCUSSION
Angiomyomatous hamartoma is a rare, primary vascular tumor of the lymph nodes occurring almost exclusively in the inguinal and femoral lymph nodes and occasionally associated with edema of the ipsilateral limb.1 A few cases with popliteal and cervical lymph node involvement have been reported.1 There are no prior reports of cases with either generalized adenopathy or hepatosplenomegaly.
The histopathogenesis of AMH remains unclear. Chan and colleagues first reported this distinct clinicopathologic entity in 1992 as a primary vascular tumor of the lymph node.1–3 The hamartomatous nature of the disease was postulated by the authors on the basis of a disorganized growth pattern of smooth muscle cells and blood vessels noted on pathology.2,3 The AMH could represent a localized malformation in a congenitally damaged lymphatic vessel system.5 Other hypothesis suggests lymphedema as a possible etiology of AMH through continuous stimulation of lymphatic vessels, which triggers vasoproliferation and eventually the vascular transformation of the lymph nodes.5
Differential diagnoses of AMH include nodal lymphangio-myomatosis, which is most prevalent in women, particularly presenting with thoracic and intra-abdominal lymph nodes and plumper HMB45 (human melanoma black 45)-positive tumor cells6; leiomyomatosis, which tends to have an intraabdominal localization with compact bundles of smooth muscle cells and insignificant vascular component; and angiomyolipoma, which typically presents with retroperitoneal nodes and HMB45-positive cells.
Treatment is either conservative or surgical, depending on clinical judgment. This is only the 19th case of AMH reported so far in the literature and the fifth reported case in which the patient presented with ipsilateral lymphedema of the limb. Importantly, it is the first reported case with generalized (axillary, subcarinal, mesenteric, inguinal and retroperitoneal) lymphadenopathy and unexplained hepatosplenomegaly.
CONCLUSION
Angiomyomatous hamartoma of the lymph nodes is an exceedingly rare diagnosis but should be considered when evaluating patients with lymphatic tumors. This patient remains relatively asymptomatic and on observation at this time and seems to have more extensive disease than prior reports in the literature.
Footnotes
Author disclosures
The authors report no actual or potential conflicts of interest with regard to this article.
Disclaimer
The opinions expressed herein are those of the authors and do not necessarily reflect those of Federal Practitioner, Frontline Medical Communications Inc., the U.S. Government, or any of its agencies. This article may discuss unlabeled or investigational use of certain drugs. Please review the complete prescribing information for specific drugs or drug combinations—including indications, contraindications, warnings, and adverse effects—before administering pharmacologic therapy to patients.
REFERENCES
- 1.Mridha AR, Ranjan R, Kinra P, Ray R, Khan SA, Shivanand G. Angiomyomatous hamartoma of popliteal lymph node: an unusual entity. J Pathol Transl Med. 2015;49(2):156–158. doi: 10.4132/jptm.2013.08.08. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Dargent JL, Lespagnard L, Verdebout JM, Bourgeois P, Munck D. Glomeruloid microvascular proliferation in angiomyomatous hamartoma of the lymph node. Virchows Arch. 2004;445(3):320–322. doi: 10.1007/s00428-004-1061-x. [DOI] [PubMed] [Google Scholar]
- 3.Chan JK, Frizzera G, Fletcher CD, Rosai J. Primary vascular tumors of lymph nodes other than Kaposi’s sarcoma. Analysis of 39 cases and delineation of two new entities. Am J Surg Pathol. 1992;16(4):335–350. doi: 10.1097/00000478-199204000-00003. [DOI] [PubMed] [Google Scholar]
- 4.Ram M, Alsanjari N, Ansari N. Angiomyomatous hamartoma: a rare case report with review of the literature. Rare Tumors. 2009;1(2):e25. doi: 10.4081/rt.2009.e25. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Piedimonte A, De Nictolis M, Lorenzini P, Sperti V, Bertani A. Angiomyomatous hamartoma of inguinal lymph nodes. Plast Reconstr Surg. 2006;117(2):714–716. doi: 10.1097/01.prs.0000197912.09044.37. [DOI] [PubMed] [Google Scholar]
- 6.Lee CH, Chang TC, Ku JW. Angiomyomatous hamartoma in an inguinal lymph node with proliferating pericytes/smooth muscle cells, plexiform vessel tangles, and ectopic calcification. Indian J Pathol Microbiol. 2015;58(2):226–228. doi: 10.4103/0377-4929.155325. [DOI] [PubMed] [Google Scholar]