Differentiated thyroid cancer is the most common malignancy of the endocrine system. Although most thyroid nodules are benign, given the high incidence of thyroid nodules in the population, it is important to understand the differences between benign and malignant thyroid cancer and the molecular alterations associated with malignancy to improve detection and signal potential diagnostic, prognostic, and therapeutic targets. Proteomics analysis of benign and malignant human thyroid tissue largely revealed changes indicating modifications in RNA regulation, a common cancer characteristic. In addition, changes in the immune system and cell membrane/endocytic processes were also suggested to be involved. Annexin A1 was considered a potential malignancy biomarker and, similarly to other annexins, it was found to increase in the malignant group. Furthermore, a bioinformatics approach points to the transcription factor Sp1 as being potentially involved in most of the alterations seen in the malignant thyroid nodules.

Thyroid cancer is a common malignancy of the endocrine system. Nodules are routinely evaluated for malignancy risk by fine needle aspiration biopsy (FNAB), and in cases such as follicular lesions, differential diagnosis between benign and malignant nodules is highly uncertain. Therefore, the discovery of new biomarkers for this disease could be helpful in improving diagnostic accuracy. Thyroid nodule biopsies were subjected to a precipitation step with both the insoluble and supernatant fractions subjected to proteome and peptidome profiling. Proteomic analysis identified annexin A1 as a potential biomarker of thyroid cancer malignancy, with its levels increased in malignant samples. Also upregulated were the acetylated peptides of annexin A1, revealed by the peptidome analysis of the supernatant fraction. In addition, supernatant peptidomic analysis revealed a number of acetylated histone peptides that were significantly elevated in the malignant group, suggesting higher gene transcription activity in malignant tissue. Two of these peptides were found to be robust malignancy predictors, with an area under the receiver operating a characteristic curve (ROC AUC) above 0.95. Thus, this combination of proteomics and peptidomics analyses improved the detection of malignant lesions and also provided new evidence linking thyroid cancer development to heightened transcription activity. This study demonstrates the importance of peptidomic profiling in complementing traditional proteomics approaches.

Pancreatic solid pseudopapillary neoplasm (SPN) is a rare malignant tumour predominantly affecting young women. The occurrence of peritoneal carcinomatosis (PC) in this setting is an even rarer condition, usually related to perioperative tumour rupture. We present a case of a 43-year-old woman who previously underwent distal splenopancreatectomy after the diagnosis of a pancreatic SPN. Thirteen years later, the patient underwent a radical hysterectomy due to a uterine myoma. Intraoperatively, a peritoneal mass was additionally found and resected. Histological examination revealed an implant with morphology compatible with pancreatic SPN. The patient was then referred to our institution. Staging MRI and CT revealed multiple nodular lesions adjacent to the left colon, suggestive of peritoneal implants. The patient was then submitted to cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) with oxaliplatin and irinotecan. Histological examination confirmed peritoneal involvement by a pancreatic SPN. The postoperative course was unremarkable. Two years after surgery, the patient remains asymptomatic with no evidence of relapse. Despite SPN being cancer with a relatively indolent evolution, one needs to be aware of a possible recurrence several years after the primary resection, mainly in patients with evidence of intraoperative tumour rupture.