External beam radiation therapy for recurrent or residual thyroid cancer: What is the best treatment time and the best candidate for long-term local disease control?

INTRODUCTION: Cervical disease control might be challenging in advanced thyroid cancer (DTC). Indications for cervical external beam radiation therapy (EBRT) are controversial. PURPOSE: To identify clinical and molecular factors associated with control of cervical disease with EBRT. METHODS: Retrospective evaluation and molecular analysis of the primary tumor DTC patients who underwent cervical EBRT between 1995 and 2022 was performed. RESULTS: Eighty adults, median age of 61 years, were included. T4 disease was present in 43.7%, lymph node involvement in 42.5%, and distant metastasis in 47.5%. Those with cervical progression were older (62.5 vs. 57.3, p = 0.04) with more nodes affected (12.1 vs. 2.8, p = 0.04) and had EBRT performed later following surgery (76.6 vs. 64 months, p = 0.05). EBRT associated with multikinase inhibitors showed longer overall survival than EBRT alone (64.3 vs. 37.9, p = 0.018) and better local disease control. Performing EBRT before radioiodine (RAI) was associated with longer cervical progression-free survival (CPFS) than was RAI before (67.5 vs. 34.5, p < 0.01). EBRT ≥2 years after surgery was associated with worse CPFS (4.9 vs. 34, p = 0.04). The most common molecular alterations were ERBB2, BRAF, FAT1, RET and ROS1 and TERT mutation was predictive of worse disease control after EBRT (p = 0.04). CONCLUSION: Younger patients, with fewer affected nodes and treated earlier after surgery had better cervical disease control. Combination of EBRT with MKI improved OS. TERT mutation might indicate worse responders to EBRT; however, further studies are necessary to clarify the role of molecular testing in selecting candidates for cervical EBRT.

Transovarial transmission of a core virome in the Chagas disease vector Rhodnius prolixus.

Triatomine assassin bugs comprise hematophagous insect vectors of Trypanosoma cruzi, the causative agent of Chagas disease. Although the microbiome of these species has been investigated to some extent, only one virus infecting Triatoma infestans has been identified to date. Here, we describe for the first time seven (+) single-strand RNA viruses (RpV1-7) infecting Rhodnius prolixus, a primary vector of Chagas disease in Central and South America. We show that the RpVs belong to the Iflaviridae, Permutotetraviridae and Solemoviridae and are vertically transmitted from the mothers to the progeny via transovarial transmission. Consistent with this, all the RpVs, except RpV2 that is related to the entomopathogenic Slow bee paralysis virus, established persistent infections in our R. prolixus colony. Furthermore, we show that R. prolixus ovaries express 22-nucleotide viral siRNAs (vsiRNAs), but not viral piRNAs, that originate from the processing of dsRNA intermediates during viral replication of the RpVs. Interestingly, the permutotetraviruses and sobemoviruses display shared pools of vsiRNAs that might provide the basis for a cross-immunity system. The vsiRNAs are maternally deposited in the eggs, where they likely contribute to reduce the viral load and protect the developing embryos. Our results unveil for the first time a complex core virome in R. prolixus and begin to shed light on the RNAi-based antiviral defenses in triatomines.