|Year : 2022 | Volume
| Issue : 2 | Page : 285-287
Angiomyomatous hamartoma of the inguinal lymph node
Supriya Verma, Gauri Nakra, Anchana Gulati
Department of Pathology, Indira Gandhi Medical College, Shimla, Himachal Pradesh, India
|Date of Submission||18-Oct-2021|
|Date of Acceptance||11-Jul-2022|
|Date of Web Publication||23-Dec-2022|
Dr. Supriya Verma
Department of Pathology, Indira Gandhi Medical College, Ridge Sanjauli Road, Lakkar Bazar, Shimla - 171 001, Himachal Pradesh
Source of Support: None, Conflict of Interest: None
Angiomyomatous hamartoma is a rare disease of the lymph nodes, particularly inguinal and femoral lymph nodes. It was first identified as a distinct entity by Chan et al. in 1992. Histologically, it is characterized by the replacement of lymph nodal parenchyma with irregularly distributed thick-walled variable-sized blood vessels, haphazardly arranged smooth muscle cells, and variable amounts of fat and fibrous tissue in a sclerotic lymphatic stroma. Only a few atrophic lymphatic follicles are seen in the subcapsular area. The exact pathogenesis is still controversial. Although this entity is very rare, its recognition is important in discriminating it from other benign and malignant vascular lesions of lymph nodes.
Keywords: Angiomyomatous hamartoma, benign vascular disease, inguinal lymph node
|How to cite this article:|
Verma S, Nakra G, Gulati A. Angiomyomatous hamartoma of the inguinal lymph node. Arch Med Health Sci 2022;10:285-7
| Introduction|| |
Angiomyomatous hamartoma (AMH) is a benign vascular disease of lymph nodes with uncertain etiology. It most commonly involves inguinal and femoral lymph nodes. Few cases have also been reported in the head-and-neck region and submandibular and popliteal locations. These lesions are one of the rare causes of asymptomatic lymphadenopathy in middle-aged individuals, causing a diagnostic challenge to the clinician. Because these lesions are benign, the treatment of choice is complete surgical excision and the prognosis is good. Knowledge regarding this entity is necessary to avoid the erroneous clinical diagnosis of lymphomas or any other metastatic malignancies. Here, we report the case of AMH in the inguinal lymph node in a 19-year-old male.
| Case Report|| |
A 19-year-old male presented with swelling in the bilateral inguinal region for 6 months, gradually progressive in size, not associated with pain. Ultrasound showed a cystic mass in the inguinal region measuring 4 cm × 3.5 cm. The left inguinal swelling was surgically excised and sent for histopathological examination. Gross examination showed two gray–white-to-gray–brown soft-tissue pieces measuring 2.8 cm × 2 cm × 0.5 cm and 1 cm × 0.6 cm × 0.3 cm, respectively. Microscopic examination of both the soft-tissue pieces revealed two matted lymph nodes with perinodal tissue. A larger lymph node revealed partial replacement of lymph node parenchyma in the hilar and medullary region by a mass of proliferating thick-walled blood vessels, smooth muscle cell fascicles, lobules of mature adipose tissue, and collagenous stroma [Figure 1] and [Figure 2]. The cortical tissue was pushed to the periphery and revealed lymphoid follicles with focally prominent germinal centers, dilated lymphatic spaces, vascular proliferation, fibrosis, and mixed inflammatory infiltrate of lymphocytes, histiocytes/Langerhans cells, plasma cells, and eosinophils in the paracortex [Figure 3]. Smaller lymph nodes revealed follicular hyperplasia with prominent germinal centers. Based on the above histopathological findings, the diagnosis of angiomyolipomatous hamartoma with chronic nonspecific lymphadenitis was given.
|Figure 1: Microphotograph revealing distortion of lymph node architecture and replacement by thick-walled blood vessels and fibrous connective tissue. Dilated lymphatic channels are also appreciated (H and E, ×10)|
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|Figure 2: Microphotograph showing clusters of mature adipose tissue and smooth muscle bundles in the parenchyma of lymph node (H and E, ×10)|
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|Figure 3: Microphotograph revealing adipose tissue clusters and thick-walled blood vessels with focal preserved atrophic lymphoid follicles (H and E, ×4)|
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| Discussion|| |
Hamartoma means an excessive, focal overgrowth of cells and tissues native to the organ in which it occurs. This term was first coined by Albrecht in 1904. The cellular elements that show excessive growth are usually mature and identical to those found in the remainder of the organ. Hamartomas can be thought of as tumor-like lesion which is like a linkage between malformations and neoplasms.
Lymph nodes can undergo vascular endothelial cell proliferation in response to a variety of stimuli, which results in conditions such as vascular transformation of sinuses, bacillary angiomatosis, inflammatory pseudotumor, angiosarcoma, or hemangioendothelioma. AMH was first defined by Chan et al. in 1992 during the analysis of primary vascular tumors of lymph nodes other than Kaposi sarcoma. It occurs most commonly in the inguinal lymph nodes in middle-aged patients. Until now, only 20 cases have been reported in the literature.
The inguinal lymph node is found to be the most common site of occurrence of AMH. It may be attributed to its most frequent location for other mesenchymal tumors. Other lymph nodes that can be involved include femoral, popliteal, submandibular, and jugular.
Microscopically, in the affected nodes, the parenchyma is partially or completely replaced with bundles of smooth muscle cells, irregularly distributed thick-walled blood vessels, and connective fibrous tissue. These changes start from the hilum and extend toward the medulla and focally into the cortex; leaving behind a thin rim of cortical lymphoid tissue with few residual atrophic lymphoid follicles. Pleomorphism, mitoses, and necrosis are absent. AMH has a benign behavior and thus extensive resection is not needed. However, recognition of AMH is important to differentiate it from other pathological conditions that may affect lymph nodes.
In a study by Magro and Grasso, the frequent presence of variable amounts of adipose tissue was noted in these lesions suggesting the nomenclature “angiomyolipomatous hamartoma” as a more appropriate term. In such cases, it should be differentiated from lymph node involvement by angiomyolipoma. The smooth muscle cells of angiomyolipoma have a prominent perivascular arrangement and express HMB-45,
Differential diagnoses of AMH include reactive lymphadenopathy to lymphoma and metastatic carcinoma. Nodal leiomyomatosis is characterized by the proliferation of smooth muscle cells but lacks prominent vascular proliferation. Lymphangiomyomatosis can be differentiated from AMH by the fact that it usually involves intrathoracic and intra-abdominal lymph nodes with smooth muscle cells arranged in bundles and groups around the ectatic vascular structures.
The exact pathogenesis of AMH is still not known. However, Sakurai et al. in their study have mentioned that impairment of lymphatic flow may be the cause. However, very few cases described in the literature have been associated with lymphedema of the ipsilateral extremity. Hence, interference of lymph flow is the cause or the effect of AMH is yet to be determined. However, Chan et al. thought that its pathogenesis can either be due to acquired etiology or may represent a reparative reaction against previous nodal inflammation.
Recurrences and metastases of AMH have not been reported. However, impaired lymphatic outflow may lead to the development of a secondary lesion after tumor resection.
| Conclusion|| |
AMH is a rare, benign vascular tumor of uncertain etiology primarily found in the inguinal lymph nodes. Its exact pathogenesis is still a matter of debate. This entity should be considered in the differential diagnosis of benign and malignant tumors of the lymph nodes. Diagnosis is based on histological examination. Complete surgical excision of the lesion is the treatment of choice.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
Arava S, Gahlot GP, Deepak R, Sharma MC, Nath D, Ashok S. Angiomyomatous hamartoma of lymph nodes: Clinicopathological study of 6 cases with review of literature. Indian J Pathol Microbiol 2016;59:206-8.
] [Full text]
Laeng RH, Hotz MA, Borisch B. Angiomyomatous hamartoma of a cervical lymph node combined with haemangiomatoids and vascular transformation of sinuses. Histopathology 1996;29:80-4.
Sakurai Y, Shoji M, Matsubara T, Imazu H, Hasegawa S, Ochiai M, et al.
Angiomyomatous hamartoma and associated stromal lesions in the right inguinal lymph node: A case report. Pathol Int 2000;50:655-9.
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;16:335-50.
Sullu Y, Gun S, Dabak N, Karagoz F. Angiomyomatous hamartoma in the inguinal lymph node: A case report. Turk J Pathol 2006;22:42-4.
Mauro CS, McGough RL 3rd
, Rao UN. Angiomyomatous hamartoma of a popliteal lymph node: An unusual cause of posterior knee pain. Ann Diagn Pathol 2008;12:372-4.
Allen PW, Hoffman GJ. Fat in angiomyomatous hamartoma of lymph node. Am J Surg Pathol 1993;17:748-9.
Magro G, Grasso S. Angiomyomatous hamartoma of the lymph node: Case report with adipose tissue component. Gen Diagn Pathol 1997;143:247-9.
Piedimonte A, De Nictolis M, Lorenzini P, Sperti V, Bertani A. Angiomyomatous hamartoma of inguinal lymph nodes. Plast Reconstr Surg 2006;117:714-6.
Barzilai G, Schindler Y, Cohen-Kerem R. Angiomyomatous hamartoma in a submandibular lymph node: A case report. Ear Nose Throat J 2009;88:831-2.
Ram M, Nazar A, Naseem A. Angiomatous hamartoma: A rare case report with review of literature. Rare Tumors 2009;25:75-8.
[Figure 1], [Figure 2], [Figure 3]