Non-Functioning Adrenocortical Carcinoma ( incidentaloma )-A Case Report and Review of Literature

Adrenocortical carcinoma is a rare endocrine tumour with poor prognosis. Herein we report a case of adrenocortical carcinoma which was non-functioning, and non-metastasizing. A female patient presented with vague abdominal pain and palpable lump on examination. A large sized adrenal mass on Ultrasonography (USG) and computed tomography was revealed. USG guided fine needle aspiration cytology was performed, the smears were highly suspicious of malignancy. Tumour was surgically excised and histopathology confirmed the final diagnosis of stage II adrenocortical carcinoma. No metastasis was seen. Rarity of non-functioning adrenocortical carcinoma prompted us to report this case. Volume 2 | Issue 5 Journal of Case Reports and Studies


Introduction
Herein, we present a case of non-functioning adrenocortical carcinoma in a 45 years old female.
A 45 years old female patient presented with complaint of dull, vague abdominal pain. It was not associated with any other complaint. On clinical examination, a lump was palpable in left hypochondrium with mild tenderness. There was no pallor, icterus and cyanosis. Pulse rate and blood pressure were normal. Urine biochemistry and microscopic examination were normal. Serum electrolytes and alkaline phosphatase value were within normal limits. Levels of adrenal hormones (urinary vanil mandelic acid and serum aldosterone) were within normal limits.
Case Report USG abdomen revealed a heterogeneous solid mass in left suprarenal region. No other abnormality was detected.
CT scan revealed a large heterogeneous enhancing mass at the superior border of left kidney (Figure 1a). It was indenting the superior pole of left kidney. Both kidneys were normal in size.
USG guided fine needle aspiration cytology (FNAC) was performed, which revealed atypical cells arranged in sheets, loosely cohesive clusters, groups as well as dispersed singly. The nuclei of these cells were round to oval to spindle shaped revealing moderate pleomorphism, coarsely clumped irregular chromatin and 1-2 prominent nucleoli at places. Cytoplasm was moderate in amount, fragile and well-defined. Background revealed scant necrosis.
In view of above findings, the tumour was reported to be malignancy of adrenocortical origin. Exploratory laparotomy was done and complete surgical excision was carried out. The mass could be separated from left kidney and other surrounding tissues clearly.
On gross examination, the tumour mass weighed 725 gms and measured 13×9×8 cms. It was well encapsulated. Cut surface revealed a variegated appearance (Figure 1b).
Histopathological examination revealed adrenocortical carcinoma with areas of necrosis, haemorrhage, high mitotic rate and atypical mitoses (Figure 2 a,b). Capsular invasion was seen. Pericapsular tissue was free from tumour.
Histopathological diagnosis of adrenocortical carcinoma was made.  Primary adrenocortical carcinomas are large tumours usually measuring more than 5 cms at presentation. Larger the tumour more is the chance of it being malignant. Because they are large, the site of origin is often difficult to determine. CT scan plays an important role in characterising the organ of origin and in defining the extent of the primary as well as assessing the presence of metastatic disease [9]. Mass lesions found incidentally by upper abdominal CT examination, so called incidentaloma may be primary adrenal tumours, metastatic malignancies or non-neoplastic lesions with an equal probability of the neoplasm being metastatic or primary. The efficacy of image -guided FNB in the diagnosis of adrenal lesions has been demonstrated in several studies [13].
The size of the tumour in the present case was >5 cms on USG, which was suspicious of malignancy. USG guided FNAC smears in this case revealed high cellularity, necrosis, nuclear pleomorphism and prominent nucleoli, which were indicative of malignancy.
Keeping in view the above findings, the adrenal mass was removed, with clearance of margins.
Differentiation between benign and malignant adrenal lesions is based on macroscopic features (tumour weight, haemorrhage, and breached or intact tumour capsule) and a microscopic diagnosis using the Weiss score, the most commonly used. The score is determined by adding up the following features: mitotic rate, atypical mitosis, nuclear grade, low percentage of clear cells, necrosis, diffuse tumour architecture, capsular invasion, sinusoidal invasion and venous invasion. A score higher than 3 is suggestive of malignancy [14].
In our case nuclear atypia, frequent and atypical mitoses, capsular invasion and necrosis were evident suggesting a diagnosis of adrenocortical carcinoma (Figure 2 a,b).
Non-functioning adrenal tumours remain a diagnostic challenge for early diagnosis and successful management, as there are no early signs and symptoms. In majority of the cases, the tumour has either invaded adjacent organs or already metastasized to distant organs at the time of initial diagnosis [9]. In this case, the distant metastasis was not observed, only capsular invasion was present. Pericapsular tissue was free of tumour.
The only curative therapy is complete surgical excision when tumours are small and localized. Complete surgical resection allows the best prognosis; an en bloc resection of the tumour and surrounding structures if indicated is recommended [3, 14,16]. If local invasion or metastasis has not occurred, it is difficult to define malignancy on histological examination. Predictors of poor survival after resection include lesions larger than 12 cms, 6 or more mitotic figures per 10 HPFs on microscopy and tumour hemorrhage [16].
The tumour in this case was in stage 2. Complete surgical excision including surrounding tissues was done. Patient is under followup and no recurrence of tumour has been reported till date, despite presence of all the predictors of poor survival.
Other features suggestive of ACC are IGF-II over expression, allelic loss of chromosome 17p13 and high level of CyclinE [14].