Early evolutionary divergence between papillary and anaplastic thyroid cancers

Background

Papillary thyroid cancer (PTC) is the most common thyroid carcinoma and exhibits an almost uniformly good prognosis, while anaplastic thyroid cancer (ATC) is less frequent and is one of the most aggressive cancers usually resistant to conventional treatment. Current hypothesis posits that ATC derives from PTC through the progressive acquisition of a discrete number of genomic alterations and implies that the mutational landscape of ATC resembles that of PTC. However, the clinical behaviour of ATC and PTC is radically different. We decided to address the disconnection between the clinical behaviour of ATC and PTC and the proposed model of the progressive development of ATC from PTC.

Patients and methods

We carried out exome sequencing of DNA from 14 ATC specimens including three cases of concomitant ATC and PTC as well as their corresponding normal DNA from 14 patients. The sequencing results were validated using droplet digital PCR. We carried out immunohistochemistry and immunofluorescence studies of the concomitant ATC and PTC cases. In addition, we integrated our sequencing results with the existing TCGA data.

Results

Most of the somatic mutations identified in the ATC component differed from the ones in PTC in the cases of concomitant ATC and PTC. The trunks of the phylogenetic trees representing the somatic mutations were short with long branches. In one case of concomitant PTC and ATC specimens, we observed an infiltration of PTC cells within the ATC component. Moreover, we integrated our results with data obtained from TCGA and observed that the most frequent mutations found in ATC presented high cancer cell fraction values and were significantly different from the PTC ones.

Conclusion

ATC diverge from PTC early in tumour development and both tumour types evolve independently. Our work allows the understanding of the relationship between ATC and PTC facilitating the clinical management of these malignancies.

SEOM clinical guidelines for the diagnosis and treatment of gastroenteropancreatic and bronchial neuroendocrine neoplasms (NENs) (2018)

NENs are a heterogeneous family of tumors of challenging diagnosis and clinical management. Their incidence and prevalence continue to rise across all sites, stages and grades. Although improved diagnostic techniques have led to earlier detection and stage migration, the improved prognosis documented over time for advanced gastrointestinal and pancreatic neuroendocrine tumors also reflect improvements in therapy. The aim of this guideline is to update practical recommendations for the diagnosis and treatment of gastroenteropancreatic and lung NENs. Diagnostic procedures, histological classification and therapeutic options are briefly discussed, including surgery, liver-directed therapy, peptide receptor radionuclide therapy, and systemic hormonal, cytotoxic or targeted therapy, and treatment algorithms are provided.

Detection of pancreatic neuroendocrine tumors: 23 years of experience

INTRODUCTION AND AIMS

Neuroendocrine tumors are of great scientific interest, given that they are difficult to diagnose and treat. Despite being relatively rare (< 1/100,000 individuals, 1-2% of the gastrointestinal neoplasias) and indolent, their potential malignancy must not be forgotten. An increase in the number of diagnosed tumors has been observed in recent years. The aim of the present study was to update a published case series of 19 patients suspected of presenting with pancreatic neuroendocrine tumor with 51 current cases, to study and compare the new results with those of the previous case series, as well as with other recent publications from Spain, the United States, China, and India.

MATERIALS AND METHODS

A retrospective, multicenter case series was conducted on 70 patients (19 cases published in 2011), whose data has been collected over a period of 23 years. The variables analyzed were: age, sex, symptomatology, tumor size, location, metastasis, final diagnosis, and surgery, among others.

RESULTS

Mean patient age was 55 years and 60% of the patients were men. Disease location was the pancreatic head in 28.5% of the patients and the tail in 27.1%, mean tumor size was 3.9cm (0.2-10cm), 71.4% of the patients had non-functioning tumors, 32.8% had metastases (100% to the liver), 74.2% of the patients were operated on, and actuarial survival was 75%.

CONCLUSIONS

Differences were observed between the previously published case series and the current results. There was an increase in incidentalomas and non-functioning tumors, but no variation in the overall survival rate. The differences with other case series (age, sex, and tumor location) were dependent on the country where the cases were compiled. The increase in tumors could be related to a higher number of diagnoses made through imaging studies and to the greater sensitivity of the devices employed.

Consensus document on the progression and treatment response criteria in gastroenteropancreatic neuroendocrine tumors

PURPOSE

Gastroenteropancreatic neuroendocrine tumors are a heterogeneous group of low incidence neoplasms characterized by a low proliferative activity and slow growth. Their response to targeted therapies is heterogeneous and often does not lead to tumor shrinkage. Thus, evaluation of the therapeutic response should differ from other kind of tumors.

METHODS

To answer relevant questions about which techniques are best in the assessment of progression or treatment response a RAND/UCLA-based consensus process was implemented. Relevant clinical questions were listed followed by a systematic search of the literature. The expert panel answered all questions with recommendations, combining available evidence and expert opinion. Recommendations were validated through a questionnaire and a participatory meeting.

RESULTS

Expert recommendations regarding imaging tools for tumor assessment and evaluation of progression were agreed upon. Available imaging techniques were reviewed and recommendations for best patient monitoring practice and the best way to evaluate treatment response were formulated.