We performed FNAC for thyroid nodules suspicious of malignancy regardless of size, whereas nodules were evaluated by FNAC in other studies. The prevalence of occult PTC at autopsy could be as high as 35%, and small occult PTCs are considered not to require treatment. Therefore, the high prevalence of thyroid cancer in our study may have been caused by active thyroid screening. Last, our findings are limited by the small sample size and the short follow-up period for examining cancer-related mortality or recurrence. In general, PTC is associated with a good prognosis. Some GDC-0449 reports show that IGF-1R tumor expression is an aggressive clinical feature and persistent despite thyroid cancer treatment. Further study should be conducted to determine the prognosis of patients with acromegaly. In conclusion, the rate of thyroid cancer was extremely high in our study, and it was the most common cancer among our patients with acromegaly. Uncontrolled acromegaly implies that persistently elevated GH and IGF-1 levels may be present in patients with a high risk of developing thyroid cancer. Therefore, regular thyroid US screening and FNAC for all suspicious thyroid nodules should be considered in all patients with newly diagnosed acromegaly and poorly controlled disease. Cyclic di-nucleotides are bacterial second messengers with functions in motility and development. Bis-cyclic dimeric guanosine monophosphate, a member of this molecule family, is produced for example by the bacterium Pseudomonas aeruginosa in which it functions in biofilm formation. It was also described to be synthesized by the eukaryotic organism dictyostelium with implications in the regulation of motility and proliferation. The related compound bis cyclic dimeric adenosine monophosphate is involved in the sporulation control of Bacillus subtilis and has host immune modulatory activity in Listeria monocytogenes infection. Immunization experiments on mice using CDNs as adjuvants suggest that they can have the immune activity of pathogen associated molecular patterns. C-di-GMP, c-diAMP, and the non-natural bis–cyclic dimeric inosine monophosphate were shown by us and others to have immune stimulatory effects and to promote balanced specific humoral and cellular responses upon immunization of mice. The recently discovered mammalian enzyme cyclic GMP-AMP synthase synthesizes the CDN cyclic GMP-AMP upon activation by foreign double stranded DNA. It was proposed that cGAMP could serve as an adjuvant in vaccine formulations, because of its capability to activate innate immune responses. We chose the intra-nasal route, because we are especially interested in developing mucosal vaccines which were shown to evoke robust mucosal on top of systemic immunity. This feature makes mucosal vaccination more favorable in combating pathogens entering via mucosal surfaces of the host. We demonstrate the in vivo adjuvant effects of cGAMP on model antigen-specific humoral and cellular immune responses in mice. We further show that cGAMP can also induce the surface expression of select activation markers on human dendritic cells in vitro. The formulation of modern subunit vaccines usually requires the addition of adjuvants to compensate for the rather low immunogenicity of isolated antigens. Not many adjuvants are approved for the use in human vaccines. Especially for mucosal vaccination, for example via the nasal route, adjuvants need to be suited to cross the mucosal barrier but at the same time have to meet high safety standards. Molecules such as cGAMP that are produced by the mammalian organism itself are expected to be of very low toxicity. Here we demonstrate the efficacy of cGAMP as an i. n. administered mucosal adjuvant in a pre-clinical mouse model.