Chapter 6: Syndromic primary hyperparathyroidism.

Area of Science:

• Endocrinology
• Genetics
• Surgical Oncology

Background:

• Syndromic primary hyperparathyroidism differs from sporadic forms with earlier diagnosis, multi-glandular disease, and higher recurrence rates.
• It is often linked to genetic syndromes like Multiple Endocrine Neoplasia (MEN) types 1, 2A, and 4, and Hyperparathyroidism-Jaw Tumor syndrome.
• These syndromes can present with varied symptoms, from asymptomatic cases in young adults to severe hypercalcemia and parathyroid tumors.

Purpose of the Study:

• To delineate the distinct clinical features and management considerations of various syndromic primary hyperparathyroidism types.
• To highlight the importance of genetic context in understanding hyperparathyroidism presentation and prognosis.
• To emphasize the need for specialized surgical care and long-term follow-up.

Main Methods:

• Comparative analysis of clinical presentations across different syndromic hyperparathyroidism types.
• Review of genetic associations and inheritance patterns (autosomal dominant).
• Discussion of diagnostic criteria and treatment implications based on syndrome classification.

Main Results:

• Multiple Endocrine Neoplasia type 1 is the most common, often asymptomatic initially but linked to recurrent stones and bone loss.
• Hyperparathyroidism-Jaw Tumor syndrome is less common but frequently symptomatic with high calcium and potential for parathyroid carcinoma.
• MEN type 2A and MEN type 4 present with less severe or later-onset hyperparathyroidism.
• Recurrence risk, especially in MEN 1, necessitates vigilant post-operative surveillance.

Conclusions:

• Syndromic primary hyperparathyroidism requires tailored management strategies based on the specific genetic syndrome.
• Multidisciplinary expert center evaluation is essential for surgical planning and treatment.
• Long-term monitoring is critical due to the significant risk of recurrence, particularly in MEN 1.