Treatment of cervical cancer

Comprehensive characterization of tumor microenvironment and m6A RNA methylation regulators and its effects on PD-L1 and immune infiltrates in cervical cancer

Understanding the role of N6-adenosine methylation (m6A) in the tumor microenvironment (TME) is important since it can contribute to tumor development. However, the research investigating the association between m6A and TME and cervical cancer is still in its early stages. The aim of this study was to discover the possible relationship between m6A RNA methylation regulators, TME, PD-L1 expression levels, and immune infiltration in cervical cancer. We gathered RNA-seq transcriptome data and clinical information from cervical cancer patients using The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases. To begin, researchers assessed the differences in m6A regulatory factor expression levels between cervical cancer and normal tissues. Clustering analysis was adapted to assess PD-L1 expression, immunological score, immune cell infiltration, TME, and probable pathways in cervical cancer samples. The majority of m6A regulators were found to be considerably overexpressed in cervical cancer tissues. Using consensus clustering of 21 m6A regulators, we identified two subtypes (clusters 1/2) of cervical cancer, and we found that WHO stage and grade were associated with the subtypes. PD-L1 expression increased dramatically in cervical cancer tissues and was significantly linked to ALKBH5, FTO, METTL3, RBM15B, YTHDF1, YTHDF3, and ZC3H13 expression levels. Plasma cells and regulatory T cells (Tregs) were considerably elevated in cluster 2. Cluster 1 is involved in numerous signature pathways, including basal transcription factors, cell cycle, RNA degradation, and the spliceosome. The prognostic signature-based riskscore (METTL16, YTHDF1, and ZC3H13) was found to be an independent prognostic indicator of cervical cancer. The tumor immune microenvironment (TIME) was linked to m6A methylation regulators, and changes in their copy number will affect the quantity of tumor-infiltrating immune cells dynamically. Overall, our research discovered a powerful predictive signature based on m6A RNA methylation regulators. This signature correctly predicted the prognosis of cervical cancer patients. The m6A methylation regulator could be a critical mediator of PD-L1 expression and immune cell infiltration, and it could have a significant impact on the TIME of cervical cancer.

Health-related quality of life and late morbidity in concurrent chemoradiation and radiotherapy alone in patients with locally advanced cervical carcinoma

Objective

Concurrent chemoradiation has improved survival of patients with cervical carcinoma. However, follow-up of randomized studies is relatively short and data on long term toxicity are scarce, as is information on their health-related quality of life. This study assesses and compares incidences of late side-effects among patients treated with radiotherapy or chemoradiation using two toxicity scoring systems, and investigates impact on health-related quality of life.

Methods

Between 1985 and 1993, 114 patients underwent radiotherapy (n=39) or chemoradiation (n=75) for stage IIA-IVB cervical carcinoma. Late side-effects were scored retrospectively by reviewing medical charts using standardised checklists, focusing on bladder- and intestinal side effects. Health-related quality of life was assessed once using the EORTC QLQ-C30.

Results

No significant differences in late treatment-related side-effects between radiotherapy and chemoradiation groups were found. Grade ≥ 2 toxicity was found in 33% (bladder), and in 6% (bowel). Only 1.8% had both grade 3-4 toxicity. Bladder syndrome with high urinary frequency, urine incontinence and small bowel toxicity had a significant impact on health-related quality of life.

Conclusion

Grade 2 are relatively frequent late side effects in curatively treated patients, but are not enhanced by the addition of chemotherapy. Their negative impact on health-related quality of life stresses the importance of new radiation techniques, aiming at reduction of these side effects.

Acute and long-term toxicity following radiotherapy alone or in combination with chemotherapy for locally advanced cervical cancer

Randomised studies in locally advanced cervical cancer patients showed that cisplatin should be given concurrently with radiotherapy, because of a better long-term survival compared to radiotherapy alone. This increases the relevance of treatment related toxicity. This review summarises the acute and long-term toxicity of radiotherapy given with or without chemotherapy for cervical cancer. Acute toxicity (all grades) of radiotherapy is reported in 61% of the patients in the rectosigmoid, in 27% as urological, in 27% as skin and in 20% as gynaecological toxicity. Moderate and severe morbidity consists of 5% to 7% gastrointestinal and 1% to 4% genitourinary toxicity. Adding chemotherapy to radiotherapy increases acute haematological toxicity to 5% to 37% of the patients and nausea and vomiting in 12% to 14%. Late effects of radiotherapy include gastrointestinal, urological, female reproductive tract, skeletal and vascular toxicity, secondary malignancies and quality of life issues. For at least 20 years after treatment, new side effects may develop. Gastrointestinal toxicity usually occurs in the first 2 years after treatment in about 10% of the patients. The incidence of moderate and severe urological toxicity can increase up to 10% and rises over time. Gynaecological toxicity usually occurs shortly after treatment while skeletal and vascular toxicity can occur years to decades later. Thus far, no increase in late toxicity has been observed after the addition of cisplatin to radiotherapy. Finally, methods to prevent or decrease late toxicity and therapeutical options are discussed. However, most randomised studies still have a limited follow-up period.