[Papillary thyroid cancer: case reports of four family cases]

Papillary thyroid cancer (PTC) is the most common endocrine malignancy, representing 80% of all thyroid cancers; only 10% of cases are manifested before age 21 and have an estimated incidence of 0.54 cases per 100,000 people. In children it is diagnosed at a more advanced stage of the disease but with good therapeutic response and very low mortality.

To present four family cases with PTC, discuss the particular characteristics and the importance of early diagnosis.

4 families with members affected by family papillary thyroid carcinoma are presented, all pediatric cases were manifested after a direct member adult case was diagnosed, therefore pediatric patients were early detected, but despite a timely treatment, the disease was advanced at the time of diagnosis. The pediatric cases are 3 females and 1 male with an average age of 12 ½ years old at diagnosis.

The family variety of papillary thyroid carcinoma (2 or more direct members affected), represents 5% of papillary cancers. It is transmitted through autosomal dominant inheritance with incomplete penetrance and variable expressivity. It occurs at a younger age than the sporadic type, and it is more aggressive with greater local invasion (32%), recurrence (20-50%) and lymphatic metastases (57 %), and it is associated with benign thyroid diseases and often, it is multifocal.

The family papillary thyroid cancer is a disease with worse prognosis than the sporadic variety; therefore, a high index of suspicion is required in affected families for early diagnosis and treatment.