Definition/General

Introduction:
-Adrenal myelolipoma is a rare benign tumor composed of mature adipose tissue and hematopoietic elements
-It represents 3-5% of adrenal incidentalomas
-It is non-functional and has excellent prognosis
-FNAC shows characteristic dual tissue components.
Origin:
-Arises from mesenchymal cells within the adrenal gland
-Contains mature adipose tissue and normal hematopoietic tissue
-Hematopoietic component includes all three cell lines
-Non-neoplastic mature tissue elements
-May represent metaplasia.
Classification:
-Classified as benign mesenchymal tumor
-Pure myelolipoma (only fat and hematopoietic tissue)
-Mixed myelolipoma (with other elements)
-Giant myelolipoma (>10 cm)
-Extra-adrenal myelolipoma (rare).
Epidemiology:
-Peak incidence in 5th-6th decades
-No sex predilection
-Usually unilateral
-Associated with endocrine disorders (Cushing syndrome, CAH)
-Increasing detection with improved imaging.

Clinical Features

Presentation:
-Asymptomatic (majority - incidentaloma)
-Flank pain (large tumors)
-Abdominal mass (giant myelolipomas)
-Retroperitoneal hemorrhage (rare complication)
-No hormonal symptoms.
Symptoms:
-Usually asymptomatic
-Dull flank pain (mass effect)
-Abdominal fullness (large tumors)
-Acute pain (hemorrhage/rupture)
-No constitutional symptoms
-No functional symptoms.

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Gross Description

Appearance:
-Well-circumscribed mass with yellow and red areas
-Yellow areas represent mature fat
-Red-brown areas represent hematopoietic tissue
-Variegated cut surface
-Size variable (1-30 cm).
Characteristics:
-Soft, lobulated mass
-Adipose tissue predominance in most cases
-Hematopoietic tissue as red-brown areas
-No necrosis typically
-Hemorrhage may be present
-Well-demarcated from adrenal.

Microscopic Description

Immunohistochemistry

Molecular/Genetic

Differential Diagnosis

Sample Pathology Report

Template Format

Sample Pathology Report

Complete Report: This is an example of how the final pathology report should be structured for this condition.

Clinical Correlation

Patient with [adrenal incidentaloma/adrenal mass] measuring [size] cm. Imaging shows [fat density areas/heterogeneous appearance]

Specimen Information

FNAC from [adrenal mass], [side], performed under [guidance method]

Specimen Adequacy

[Adequate/Inadequate] for cytological interpretation. [Both tissue components/Limited sampling] noted

Cytological Findings

Smears showing [mature adipocytes] and [hematopoietic elements]. [Trilineage hematopoiesis/Megakaryocytes] identified

Adipose Component

[Mature adipocytes/Normal fat morphology/No lipoblasts] observed

Hematopoietic Component

[Erythroid cells/Myeloid cells/Megakaryocytes/Lymphocytes] representing normal hematopoietic tissue

Background

Background shows [mixed tissue elements/no necrosis/no atypical features]

Cytological Diagnosis

[Benign] - Features consistent with adrenal myelolipoma

Imaging Correlation

Cytological findings correlate with imaging appearance of [fat density areas/heterogeneous mass]

Recommendations

[Clinical correlation/Conservative management/Surgical consultation] based on size and symptoms

Note

Myelolipoma is benign lesion. Management depends on size and symptoms. Small asymptomatic lesions can be observed