Adrenal Castleman's Disease: Case Report and Review of Literature.

Castleman's disease is a rare lymphoproliferative disorder of poorly understood etiology. It is most commonly located in the mediastinum. Castleman's disease mimicking adrenal neoplasm is a very rare differential diagnosis and unusual presentation. We report a rare suprarenal unicentric hyaline vascular variant of the disease in a 16-year-old boy with atypical symptoms mimicking an adrenal neoplasm. Copyright:

INTRODUCTION

Castleman's disease is a rare disorder, first defined by Castleman in 1956 as a distinct clinicopathological entity.[1] Two-thirds are located in the mediastinum and rest occur at extrathoracic locations such as axilla, neck, groin, mesentery, and retroperitoneal space. It is classified based on the clinical presentation and histopathological variant. The clinical subtypes are unicentric and multicentric. The histopathological variants are hyaline vascular, plasma cell, and mixed type.[2] We hereby report a case of hyaline vascular variant at the adrenal gland.

CASE REPORT

A 16-year-old boy presented with dull pain in the left upper abdomen with weight loss of 10 kg over 4 months. He had no significant past medical or surgical history. Physical examination revealed nontender, soft abdomen, without palpable mass or peripheral lymphadenopathy. Contrast enhanced computer tomography (CECT) scan of chest and abdomen showed a lobulated, well-circumscribed, enhancing mass of 53 mm × 51 mm × 55 mm with necrotic area, occupying the left suprarenal region [Figure 1]. There is no significant mediastinal mass or retroperitoneal lymph nodes. Laboratory tests and 24-h urine vanillylmandelic acid and metanephrines and plasma metanephrines were normal. He was taken up for surgery with a provisional diagnosis of nonfunctioning adrenal neoplasm. Intraoperatively, a mass of 5.5 cm × 5 cm × 6 cm was located in the left suprarenal region with multiple feeding vessels from the aorta and the left renal artery. Adrenal gland was not separately made out from the mass and it was removed en bloc. Grossly, the mass was well encapsulated with grayish white cut surface area. Histopathology revealed lymphoid follicles with thickened mantle zones and lymphocytes arranged in concentric rings [Figure 2]. There was vascular proliferation and hyalinization of vessel wall, based on which diagnosis of hyaline vascular Castleman's disease was made. His postoperative recovery was uneventful and no adjuvant therapy was considered. He is on regular follow-up without recurrence and disease free at 6 months.

Figure 1

Contrast enhanced computed tomography of abdomen showing lobulated, circumscribed, enhancing left suprarenal mass with area of necrosis. Adrenal gland is not separately seen

Figure 2

Photomicroscopy shows lymphoid follicles arranged in a concentric fashion with hyalinization and adjacent hyalinized blood vessels. (Hematoxylin and Eosin, ×10)

DISCUSSION

Castleman's disease is a rare neoplasm occurring most commonly in the mediastinum. Only 12% cases occur in the abdomen of which only 12 cases have been reported previously in the adrenal region [Table 1].[345678910111213] The etiology of Castleman's disease is poorly understood with one possible hypothesis being a defect in the immune regulation.[2]

Table 1

Reported cases of adrenal region Castleman’s disease

Author	Age (years)/sex	Presenting symptom	Longest size (cm)	CT finding	Intraoperative finding
Debatin et al.[3]	43/female	Hypertension	6	Homogenous enhancement	Adrenal gland replaced by disease
Gupta et al.[4]	25/male	Vague upper gastrointenstinal symptoms	8	Calcified lesion	Adrenal replaced by disease
Chen et al.[5]	51/female	Poor appetiteLoss of weight	5.2	Well-defined enhancing mass with multiple areas of low attenuation	Mass separate from adrenal
Mussig et al.[6]	51/male	OverweightHypertension	3	Homogenous enhancement	Adrenal gland invasion with multiple lymph node
Santomauro et al. (2011)[7]	16/male	Incidentaloma	4.8	Enhancing mass	Mass separate from adrenal gland
Otto et al.[8]	33/male	Incidentaloma	5	Small focus of enhanced density	Tumor separate from adrenal
Cao et al.[9]	51/female	Abdominal pain	11	Enhancing mass	NA
Cao et al.[9]	56/male	Incidentaloma	8	Heterogenous mass	NA
Hong et al.[10]	65/female	Abdominal discomfortHypertension	5	Highly enhancing mass with peripheral enhancement, multiple lymph nodes	Adrenal replaced by disease with multiple nodes
Sundar et al.[11]	44/female	Abdominal pain	6.7	Well defined with heterogenous enhancement	Mass separate from adrenal
Chen et al.[12]	26/female	Left flank pain	4	Non enhancing mass	Adrenal replaced by disease
Guo et al.[13]	59/male	Abdominal pain	5.1	Enhancing heterogenous mass	Mass adhered to surrounding structures
Our case	16/male	Abdominal pain, weight loss	5.5	Enhancing heterogenous mass	Adrenal replaced by disease

CT – Computed tomography, NA – Not available

The age of presentation in suprarenal disease has ranged from 16 years to 65 years without gender predilection. The most common presenting symptom for unicentric disease in suprarenal region has been abdominal pain although many have presented as incidentalomas.[345678910111213] In our case, the patient is a 16-year-old male and presented with weight loss and abdomen pain which is an uncommon presentation for the localized unicentric hyaline vascular type Castleman's disease. In view of age, symptoms and high geographical burden, a differential diagnosis of tuberculosis was also kept, however, majority of patients with active or recently acquired tubercular disease (<2 years) have bilateral adrenal enlargement, while calcification and atrophy are visualized in more remote infection or inactive disease.[14]

Although imaging plays a key role in the identification of adrenal masses, it may not be conclusive in identifying Castleman's disease. Various authors have reported features of well-defined enhancing solid mass with homogenous soft tissue density, calcified lesion or with multiple lymph nodes on CECT.[10] Our patient had a heterogenous mass with necrotic areas. One author has described MR features of adrenal disease as hypointense in T1 and hyperintense in T2 with a delayed washout although they emphasized that similar features can be seen in lymphoma also.[3]

The hyaline vascular type accounts for 80%–90% of localized disease and is usually asymptomatic but may cause pressure effect due to large size and is rarely associated with systemic features.[4] As in mediastinum, three different disease patterns are seen in suprarenal region also: solitary noninvasive mass; a dominant infiltrative mass with associated lymphadenopathy; matted lymphadenopathy without a dominant mass.[15] In other sites, a solitary noninvasive mass is the most common presentation, but in the suprarenal region, 50% patients had adrenal gland infiltration. In our case, the mass was 6 cm with lobulations but well encapsulated without any infiltration of adjacent structures. Such findings are also seen in other adrenal malignancies also.

Castleman's disease involving a single site is usually benign, however, multicentric variety can transform into malignant lymphoma.[2] The treatment of unicentric hyaline vascular Castleman's disease is complete surgical excision which is curative.[13] Our case of 16-year-old boy with symptomatic presentation and uncommon computed tomography findings illustrates a divergent presentation of this rare pathology and need for histopathological confirmation.

CONCLUSION

The unicentric hyaline vascular variety of Castleman's disease masquerading as an adrenal neoplasm is a very rare presentation. It is to be considered in the differential diagnosis of nonfunctional adrenal neoplasm.

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Conflicts of interest

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