Melanotic schwannoma of adrenal gland is very rare entity with only two series and less than 100 cases reported in literature. We report a case of melanotic schwannoma.

1. Melanotic Schwannoma of Adrenal Gland - A Rare Entity/
Diagnostic Dilemma

2. a p o l l o m e d i c i n e 1 0 ( 2 0 1 3 ) 7 7 e8 1
Available online at www.sciencedirect.com
journal homepage: www.elsevier.com/locate/apme
Case Report
Melanotic schwannoma of adrenal gland e A rare entity/
diagnostic dilemma
Feroz Amir Zafar a, Ishfaque A. Geelani a, Pravin Govardhane a, H. Girish a,
D.V.S.L.N. Sharma a, V. Rajagopal a,*, Meenakshi Swain b, G. Swarnalatha b
a
b
Department of Urology, Apollo Hospitals, Hyderabad, India
Department of Histopathology, Apollo Hospitals, Hyderabad, India
article info
abstract
Article history:
Introduction and objective: Melanotic schwannoma of adrenal gland is very rare entity with
Received 31 January 2013
only two series and less than 100 cases reported in literature. We report a case of melanotic
Accepted 2 February 2013
schwannoma.
Available online 9 February 2013
Case report: A 62 years old man, a resident of Tanzania presented with 6 months history of
lower urinary tract symptoms (LUTS) for which he was evaluated and a right adrenal mass
Keywords:
Melanotic schwannoma
detected incidentally on ultrasound.
He is known case of hypertension and hypothyroidism for which he is taking regular
Melanoma
medications. On general examination pulse was 80/min, regular and BP was130/80 mm of
Nerve sheath tumor
Hg. Abdominal examination was unremarkable. MDCT examination revealed a right ad-
Adrenal schwannoma
renal mass (4 Â 4.8 cm) showing mild enhancement post contrast study with central area of
relatively less enhancement showing no significant contrast washout on delayed study.
The provisional diagnosis was ? pheochromocytoma, ? malignant. Functional study was
found to be normal. Laparoscopic exploration was done and mass excised. Gross pathological examination showed a single globular circumscribed soft tissue mass measuring
4.5 Â 4 Â 3 cm and weighing 50 g with a nodular surface. The cut surface was black with
a central golden brown area measuring around 2.2 Â 1.8 cm.
A diagnosis of malignant melanoma was considered, however in view of circumscription bland nuclei, absent of nucleoli, very few mitoses and presence of nerve fascicles;
a diagnosis of melanotic schwannoma was favored. The patient was advised regular follow-up.
Conclusion: Melanotic schwannoma of adrenal is a very rare entity and every effort should
be made to rule out melanoma.
Copyright ª 2013, Indraprastha Medical Corporation Ltd. All rights reserved.
1.
Introduction
Melanotic schwannoma of the adrenals is a rare, accounting
for only 1e3% of all schwannomas and only 1% of all
retroperitoneal tumors.1,2 They are circumscribed but unencapsulated, grossly pigmented tumor, composed of cells
having the ultra structure and immunophenotype of Schwann
cells that contain melanosomes and are reactive for
* Corresponding author.
E-mail address: raja_urol@rediffmail.com (V. Rajagopal).
0976-0016/$ e see front matter Copyright ª 2013, Indraprastha Medical Corporation Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.apme.2013.02.001

3. 78
a p o l l o m e d i c i n e 1 0 ( 2 0 1 3 ) 7 7 e8 1
Fig. 1 e CECT of abdomen & pelvis (coronal, saggital &
transverse planes) showing the right adrenal mass (white
arrow).
Fig. 3 e CECT of abdomen & pelvis (coronal, saggital &
transverse planes) showing the right adrenal mass (white
arrow).
melanoma markers. Cytological atypia is not uncommon. The
vast majority of non-psammomatous tumors affect spinal
nerves and paraspinal ganglia, whereas the psammomatous
lesions also involve autonomic nerves of viscera, such as the
intestinal tract, adrenal and heart. About 50% of patients with
psammomatous melanotic schwannoma have the rare
inherited autosomal-dominant disorder Carney complex type
Fig. 2 e CECT of abdomen & pelvis (coronal, saggital &
transverse planes) showing the right adrenal mass (white
arrow).
Fig. 4 e Laparoscopic views of the darkly pigmented tumor
(yellow arrow).

4. a p o l l o m e d i c i n e 1 0 ( 2 0 1 3 ) 7 7 e8 1
Fig. 5 e Laparoscopic views of the darkly pigmented tumor
(yellow arrow).
I (CNC) characterized by facial pigmentation, Cardiac myxoma, and endocrine overactivity. A correct preoperative
diagnosis is difficult to make and these tumors are often
misdiagnosed as other soft tissue lesions occurring in the
retroperitoneum.
Over 80 cases of one or more tumors have been reported in
literature so far.3 We describe a case of melanotic schwannoma of the adrenal gland.
2.
Case presentation
Sixty two years gentleman, resident of Tanzania presented
with h/o lower urinary tract symptoms (LUTS) since >6
months and an incidentally detected right adrenal mass. He
gave a past history of hypertension and hypothyroidism
Fig. 6 e Resected specimen (pigmented).
79
Fig. 7 e Cut section of the tumor (heterogeneous).
which was under control with medications. On clinical examination, pulse e 80/min, BP e 130/80 mm of Hg. General
examination e No pallor/icterus/cyanosis/clubbing/edema
feet. P/A e soft, non-tender, no mass was palpable. Investigations revealed Hb-12 g%, TLC-4100/mm,3 S. creatinine
e 1.2 mg%, RBS e 74 mg%, Metanephrines (24 h urine) e
1.0 mg/day, VMA (24 h urine) e 8.7/day, S. cortisol (dexamethasone suppression test) e 0.56 mg/dl. CT scan (Figs. 1e3)
showed a right adrenal mass (4 Â 4.8 cm) showing mild
enhancement post contrast study with central area of relatively less enhancement showing no significant contrast wash
out on delayed study (? pheochromocytoma/? malignant).
At Laparoscopic exploration, a heterogeneous, darkly pigmented (almost black) unencapsulated neoplasm was found
in the right retroperitoneal space, medially displacing the
inferior vena cava and clearly separated from the kidney and
the renal vein, which are pushed downward. The tumor was
completely excised (Figs. 4 and 5).
The specimen was sent for histopathological examination.
Fig. 8 e Low power 103 H&E stain.

5. 80
a p o l l o m e d i c i n e 1 0 ( 2 0 1 3 ) 7 7 e8 1
Fig. 9 e 203 showing tumor attached to nerve fascicles.
Fig. 11 e Immunohistochemistry showing positive S 100.
2.1.
Gross description
Single globular circumscribed soft tissue measuring
4.5 Â 4 Â 3 cm & weighing 50 g. External surface was nodular
(Fig. 6). Cut surface was black with a central golden brown area
measuring around 2.2 Â 1.8 cm (Fig. 7).
2.2.
Microscopically
Lobules and nests of tumor cells with large areas of necrosis
and hemorrhage. The tumor cells are spindle shaped and arranged in intersecting fascicles. Tumor cells have moderate ill
defined fibrillary cytoplasm and have elongated bland vesicular nuclei with few showing nuclear grooves (Fig. 8).
Abundant brownish black pigment is seen with in tumor
cells and also within the histiocytes (Fig. 10). Few mitoses
were seen averaging 1e2/10 hpf. Prominent nuclei typical of
melanoma are not seen. Perl’s stain is positive in the pigment
in hemosiderin laden macrophages and negative in pigment
in tumor cells (Fig. 11). A few nerve fascicles are seen at the
periphery adherent to the tumor (Fig. 9).
3.
Melanotic schwannomas (MS) were first described in 1932 by
Millar.4 These tumors are rare, with approximately 80 cases
reported in the literature to date.3
Melanotic schwannomas are of neural crest origin probably caused by the neoplastic proliferation of a common precursor cell for both Schwann cells and melanocytes.5,6
Schwannoma is a neurogenic tumor usually arising between
the third and sixth decades of life, with an equal predilection
for men and women. It may occur in any organ or nerve trunk
with the exception of cranial nerves I and II, which lack
Schwann cells A preoperative diagnosis is very difficult to
make because of the lack of typical imaging features (US, CT
and MRI) that distinguish schwannomas from retroperitoneal
malignancies.7 Even with accurate preoperative imaging and
intraoperative frozen section analysis, the presence of a possible malignancy cannot be excluded, so a definitive diagnosis
can be obtained only through careful histological and immunohistochemical examination. Surgical excision is considered
the treatment of choice for these tumors, which respond
poorly to radiation and chemotherapy.8 We were unable to
make a correct preoperative diagnosis. The following differential diagnosis was considered: malignant melanoma, melanotic schwannoma, pigmented pheochromocytoma and
leiomyosarcoma. There was a diagnostic dilemma and malignant melanoma was strongly considered, however in a view
of the circumscription, bland nuclei, absence of nucleoli, very
few mitoses and the presence of nerve fascicles, a diagnosis of
a melanotic schwannoma was finally favored.
4.
Fig. 10 e H&E (403) e Spindle cells running in fascicles with
intracytoplasmic melanin pigment.
Discussion
Conclusion
Melanotic schwannoma is a rare variant of schwannoma
composed of melanin-producing cells with ultrastructural
features of Schwann cells. Distinguishing between this tumor
and malignant melanoma is important in planning management. Total resection should be performed. Appropriate longterm follow-up is needed for all melanotic schwannomas.

6. a p o l l o m e d i c i n e 1 0 ( 2 0 1 3 ) 7 7 e8 1
Conflicts of interest
4.
All authors have none to declare.
references
5.
6.
1. Ueda M, Okamoto Y, Ueki M. A pelvic retroperitoneal
schwannoma arising in the right paracolpium. Gynecol Oncol.
1996;60:480e483.
2. Hayasaka K, Tanaka Y, Soeda S, Huppert P, Claussen CD. MR
findings in primary retroperitoneal schwannoma. Acta Radiol.
1999;40:78e82.
3. Zhang HY, Yang GH, Chen HJ, et al. Clinicopathological,
immunohistochemical, and ultrastructural study of 13 cases of
7.
8.
81
melanotic schwannoma. Chin Med J (Engl).
2005;118(17):1451e1461.
Millar W. Malignant melanotic tumor of the ganglion cells
arising from the thoracic sympathetic ganglion. J Pathol.
1932;35:351e357.
Vallat-Decouvelaere A-V, Wassef M, Lot G, et al. Spinal
melanotic schwannoma: a tumour with poor prognosis.
Histopathology. 1999;35:558e566.
Watson JC, Stratakis CA, Bryant-Greenwood PK, et al.
Neurosurgical implications of Carney complex. J Neurosurg.
2000;92:413e418.
Hughes MJ, Thomas JM, Fisher C, Moskovic EC. Imaging
features of retroperitoneal and pelvic schwannomas. Clin
Radiol. 2005;60:886e893.
Daneshmand S, Youssefzadeh D, Chamie K, et al. Benign
retroperitoneal schwannoma: a case series and review of the
literature. Urology. 2003;62:993e997.

7. A o oh s i l ht:w wa o o o p a . m/
p l o p a : t / w .p l h s i lc
l
ts p /
l
ts o
T ie: t s / ie. m/o p a A o o
wt rht :t t r o H s i l p l
t
p /w t c
ts
l
Y uu e ht:w wy uu ec m/p l h s i ln i
o tb : t / w . tb . a o o o p a i a
p/
o
o
l
ts d
F c b o : t :w wfc b o . m/h A o o o p a
a e o k ht / w . e o k o T e p l H s i l
p/
a
c
l
ts
Si s ae ht:w wsd s aen t p l _ o p a
l e h r: t / w .i h r.e/ o o H s i l
d
p/
le
A l
ts
L k d : t :w wl k d . m/ mp n /p l -o p a
i e i ht / w . e i c c a y o oh s i l
n n p/
i
n no o
a l
ts
Bo : t :w wl s l e l . /
l ht / w . t a h a hi
g p/
e tk t n