Thyroid Cancer 101: It is a Disease That Effects First Degree Family Members
Does papillary thyroid cancer run in families? Answer is yes.
Sporadic thyroid cancer: usual form of thyroid cancer that does not have a genetic component and does not run in families.
Most papillary thyroid cancers occur in individuals without a family history of thyroid cancer (sporadic thyroid cancer). Known factors that increase the chance of developing papillary thyroid cancer are radiation exposure to the head and neck area, iodine deficiency and history of thyroid diseases. Approximately 5% of thyroid cancers are thought to run in families (familial thyroid cancer). Previous studies showed that patients having a relative diagnosed with papillary thyroid cancer have a 5-10 fold higher chance of developing the thyroid cancer themselves and are more likely to have a more aggressive form of cancer. It is thus important to detect and treat the at-risk relatives at an early stage. In this study, the authors studied the familial risk of developing papillary thyroid cancer in large Utah population.SUMMARY OF THE STUDY
A total of 4460 patients diagnosed with papillary thyroid cancer in Utah were compared to individuals similar by sex, age and place of birth but without known thyroid disease. The chance of developing papillary thyroid cancer among first, second and third degree relatives was then measured.
A 5-fold higher chance of developing papillary thyroid cancer was seen among first degree relatives. This was especially true for brothers and sisters (6.8-fold). Risk of developing papillary thyroid cancer among second degree (grandparents, aunts, uncles, cousins: 2.24-fold) and third degree (first cousins: 1.76-fold) relatives was much lower, but still significantly higher than individuals without known thyroid disease.
WHAT ARE THE IMPLICATIONS OF THIS STUDY?
The results of this study confirm prior reports that there is an increased risk of developing thyroid cancers in families.
The author does not recommend screening of families, but case finding among family members would be valuable to find the cancer early. If you had a family member with thyroid cancer and you knew there was a significant increased risk of you having thyroid cancer, would you want to have a neck ultrasound to see if you had nodules that were suspicious and that needed a biopsy? Most would say yes, but some would rather not know.
Family thyroid cancer
Familial Non-Medullary Thyroid Cancer – is a clear clinical distinct entity characterized by multifocality and a more severe phenotype and is defined as the presence of two or more first-degree relatives affected by differentiated thyroid cancer of follicular origin. In some cases, the disease is associated with rare hereditary syndromes such as Carney complex, Werner syndromes, FAP and Cowden syndromes. However, in the majority of the cases, patients have thyroid cancer as the only disease manifestation. Several studies have tried to identify the genetic alteration(s) responsible for the development of FNMTC with promising results although none of the genes/loci identified accounts for the majority of cases of FNMTC and cannot be generalized to the larger at-risk population.