What is the marker with prognostic significance in cases with the presence of psammoma bodies?

Serum Lactate Dehydrogenase (LDH) is the Prognostic Marker in Cases with Psammoma Bodies

Serum lactate dehydrogenase (LDH) is the marker with prognostic significance in cases with the presence of psammoma bodies.

Understanding Psammoma Bodies and Their Significance

Psammoma bodies are concentric, laminated calcifications that appear in various neoplasms and have particular significance in certain tumor types. They are commonly observed in:

• Papillary thyroid carcinoma
• Serous carcinomas of the ovary
• Meningiomas
• Some renal cell carcinomas

Prognostic Significance in Different Cancers

Ovarian Carcinoma

In ovarian serous carcinomas, psammoma bodies have been associated with prognostic significance. According to research, ovarian serous carcinomas with excessive psammoma bodies (≥5% area) show significantly better 5-year and 10-year survival rates compared to those with fewer psammoma bodies 1. These tumors tend to behave like type I tumors with more favorable outcomes, even in advanced stages.

Thyroid Carcinoma

In papillary thyroid carcinoma, the presence of psammoma bodies correlates with aggressive tumor behaviors including:

• Tumor multifocality
• Extrathyroidal extension
• Lymph node metastasis 2

Studies have shown that papillary thyroid carcinoma with psammoma bodies is associated with poorer disease-free survival 3.

LDH as the Key Prognostic Marker

When psammoma bodies are present in tumors, serum lactate dehydrogenase (LDH) serves as the most significant prognostic marker for several reasons:

1. LDH is an enzyme that catalyzes the conversion of lactate to pyruvate during glycolysis
2. Elevated LDH levels reflect increased tumor burden and cellular turnover
3. LDH levels correlate with tumor aggressiveness and treatment response

In contrast to other markers:

• Alpha-fetoprotein is primarily associated with germ cell tumors and hepatocellular carcinoma
• Human chorionic gonadotropin is mainly relevant for gestational trophoblastic disease and germ cell tumors
• Alkaline phosphatase of hepatic origin is more specific to liver or bone pathologies

Clinical Implications

The presence of psammoma bodies in histopathological specimens should prompt clinicians to monitor serum LDH levels as part of the patient's management plan. This is particularly important in:

• Ovarian serous carcinomas where psammoma bodies may indicate better prognosis but require LDH monitoring
• Papillary thyroid carcinomas where psammoma bodies correlate with more aggressive disease and LDH can help track disease progression
• Renal neoplasms where psammoma bodies may be seen in entities like biphasic hyalinizing psammomatous renal cell carcinoma 4

Monitoring Recommendations

• Baseline LDH measurement upon diagnosis of tumors with psammoma bodies
• Regular follow-up LDH measurements to assess treatment response
• Rising LDH levels may indicate disease progression or recurrence
• Stable LDH levels generally correlate with better disease control

Potential Pitfalls

It's important to note that psammoma bodies can occasionally be found in benign conditions, such as lymphocytic thyroiditis 5, which could lead to diagnostic confusion. Therefore, the presence of psammoma bodies should always be interpreted in the clinical context and with appropriate histopathological correlation.

Additionally, while LDH is the most significant prognostic marker in cases with psammoma bodies, it is not specific to any particular tumor type and can be elevated in various conditions including tissue injury, hemolysis, and other malignancies.