Abstract
Introduction
Adenomatoid tumors most commonly occur in the genital tract including the epididymis, uterus, or fallopian tube. 1 Interestingly, these tumors have also been reported to occur in the adrenal gland.1–6 Adrenal adenomatoid tumors are derived from mesothelial cells from mesothelial rests within the adrenal gland. These rests are likely present due to the close embryological relationship between the adrenal glands and the Mullerian tract.6–7 This report represents the 29th case of an adrenal adenomatoid tumor in the literature, but is only the second case described in a patient with human immunodeficiency virus and the first case in which positron emission tomographic scanning was used as part of the diagnostic work-up.
Materials and Methods
We describe the clinical course, laboratory, radiographic, and microscopic findings of a patient with human immunodeficiency virus and an adenomatoid tumor of the right adrenal gland. A review of the literature was also done via electronic searches through PubMed for articles from 1965 to 2008 that contained the following search terms,
Results
Report of a case
AH is a 22 year-old African-American male with a past medical history of human immunodeficiency virus on HAART (Highly Active Anti-Retroviral Therapy) who was noted to have an incidental adrenal mass on computed tomography of the chest done as a follow-up study for mediastinal lymphadenopathy. No previous adrenal masses were noted on previous computed tomographic imaging.
The patient denied any symptoms of palpitations, diaphoresis, flushing, or uncontrolled high blood pressure. He subsequently had a magnetic resonance imaging scan to further characterize the adrenal mass. It was a right adrenal mass that measured 2.7 by 1.6 by 2.3 cm in size with atypical enhancement patterns with gadolinium contrast. The patient underwent a complete adrenal hormonal work-up. His 24-hour urine catecholamines, serum aldosterone, and plasma renin activity were all normal. Serum cortisol level was mildly elevated, but his urinary cortisol level was normal. Prior to surgical referral, the patient also underwent a follow-up positron emission tomographic scan which demonstrated increased uptake of 3.4 SUV. Based on the above findings, the differential diagnosis included a non-functioning adrenal adenoma or malignancy. The patient underwent a laparoscopic right adrenalectomy with no post-operative complications on follow-up examination seven months later.
Pathologic findings
On gross examination, the adrenal gland was 5.5 by 3.0 by 1.0 cm in size with a well-circumscribed, firm, tan-gray cortical mass that measured 2.5 by 2.5 by 1.0 cm. No areas of necrosis or hemorrhage were identified in the mass. On light microscopy examination, the adrenal mass was composed of epithelioid cells forming nests, cords, and tubules. There were no areas of necrosis, mitotic activity, or significant atypia. On immmunohistochemical examination, the cells in the adrenal mass were positive for calretinin and cytokeratins (AE1/3 and CAM 5.2) and negative for CD31, CD34, and Factor VIII. These morphological and immunohistochemical features were consistent with an adenomatoid tumor (Figures 1–3).
The tissue at far right in this image is normal adrenal cortical tissue. The native adrenal tissue is replaced or extensively infiltrated by tumor cells forming small solid nests as well as anastomosing channels and tubules of variable size and shape.
Lesional cells range from plump epithelioid cells to flattened cells resembling endothelial cells, and many exhibit prominent vacuolization, to an extent that may mimic a signet-ring appearance with apparent intracytoplasmic lumina. They do not exhibit nuclear pleomorphism, necrosis or mitotic activity.
Immunostain for calretinin highlights the tumor cells, in keeping with their mesothelial derivation.
Literature review
As illustrated in Table 1 and Table 2, there have been 29 reported cases of adenomatoid tumors of the adrenal gland in the recent English-language medical literature.1–19 Almost all of these cases were in male patients (97%) with a mean age of 40Literature Review10 years (range=22–64). The laterality of these tumors is approximately 14 (48%) tumors on the right side and 14 (48%) tumors on the left side (laterality was unknown in one patient) with an average size of 4.6±4.0 cm (range=0.5–16.7 cm). Many of these tumors were either discovered as part of an autopsy or incidentally found as part of a diagnostic work-up for various symptoms including: painless hematuria, hypertension, abdominal pain, and Cushing's syndrome. Various imaging modalities were used including computed tomography (n=18), magnetic resonance imaging (n=6), ultrasound (n=3), and positron emission tomography (n=1). Interestingly, eight (31%) patients had adenomatoid tumors that extended into the periadrenal adipose tissue or the adrenal gland capsule. However, no recurrences have been reported with a median follow-up time of 33 months (range=3 to 177 months).
clinical data from review of the medical literature
Pathological data from review of the medical literature.
In terms of tumor color, these tumors have been described as being white, tan, fleshy, pale-yellow, opaque, and grayish. In terms of tumor consistency, however, these tumors have been described as being firm, smooth, cystic, solid, and well-circumscribed. Other histopathological characteristics have been noted in adenomatoid tumors including: heterotopic ossification, lymphoid aggregates, sites of mucin production, and cells with a signet ring-like appearance.
Adenomatoid tumors have been found to stain positive with a wide variety of agents including: vimentin, calretinin, cytokeratins (CAM 5.2, CKAE1, and CKAE3), MAK-6, D2–40, OV-TL 12/30, and MNF 116. A few studies have examined adenomatoid tumors using electron microscopy and found various features including: numerous long, thin, bushy microvilli with well developed desmosomes, basal laminae, and cytoplasmic fibrillar networks.
Discussion
Patients with human immunodeficiency virus (HIV) frequently present with a number of associated neoplasms, often as a result of their immunosuppression. It is very unusual for HIV-positive patients to present with adrenal gland neoplasms other than Kaposi's sarcoma or lymphoma. HIV-positive patients may also present with infectious etiologies that may present as an adrenal mass, including cytomegalovirus necrotizing adrenalitis, mycobacterium, cryptococcus, or other fungal infections.20,21 This case represents only the second reported case of an adenomatoid tumor in a patient with HIV. However, it is unknown how many other patients with reported adrenal adenomatoid tumors were tested for HIV. It is possible that the incidence of adrenal adenomatoid tumors in patients with HIV may increase as a consequence of anti-retroviral therapies or chronic immunosuppression.
Although the first adenomatoid tumor was described in 1945, adrenal adenomatoid tumors were not well described until the late 1980's.
22
This result may be due to the increasing use of diagnostic computed tomographic imaging in detecting adrenal
Finally, this case emphasizes that although adrenal adenomatoid tumors have been described in the past as extending into the perirenal adipose tissue, the clinical behavior is definitely benign. 10 Adrenal adenomatoid tumors may be misclassified as lymphangiomas or adenocarcinomas because of infiltrative borders into the adrenal capsule or periadrenal adipose tissue. 24 These tumors can be reliably distinguished from adrenal adenocarcinoma as adenomatoid tumors stain positive for keratin and do not produce mucin. Based on Table 1, local resection limited to the adrenal gland itself without any specific post-operative surveillance protocol appears to be sufficient treatment of adrenal adenomatoid tumors. Laparoscopic adrenalectomy which is the current gold-standard for the surgical resection of adrenal tumors can be safely employed in the case of adrenal adenomatoid tumors.
