Correlation between TXNRD1/HO-1 expression and response to neoadjuvant chemoradiation therapy in patients with esophageal squamous cell carcinoma

Background Thioredoxin reductase 1 (TXNRD1) and heme oxygenase-1 (HO-1) are both involved in the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway and play key roles in antioxidant responses. In patients with esophageal squamous cell carcinoma (ESCC), the correlation between the expression of these two proteins and the therapeutic response to neoadjuvant chemoradiation therapy (NACRT), as well as the difference in their expression after chemoradiotherapy, remains unknown. Methods Proteins involved in the Nrf2 pathway were immunolocalized in carcinoma cells in ESCC patients on NACRT with 5-fluorouracil and cisplatin, followed by esophagectomy. The 8-hydroxydeoxyguanosine (8-OHdG) levels were used to quantify reactive oxygen species. The changes in immunoreactivity before and after NACRT (Δ) were assessed. Results Tumor reduction following NACRT was significantly attenuated in pre-therapeutic biopsy specimens associated with high HO-1 status. TXNRD1Δ, HO-1Δ, and 8-OHdGΔ were significantly different in the ineffective and effective groups. The overall survival was significantly lower in high Nrf2 and TXNRD1 groups. In addition, high TXNRD1 expression was an independent prognostic factor in the multivariate analysis of overall survival. Conclusions The study findings indicate that HO-1 status in pre-therapeutic biopsy specimens could predict response to NACRT, and TXNRD1 status could predict overall survival of ESCC patients.

Pathologic Complete Response Prediction after Neoadjuvant Chemoradiation Therapy for Rectal Cancer Using Radiomics and Deep Embedding Network of MRI

Assessment of magnetic resonance imaging (MRI) after neoadjuvant chemoradiation therapy (nCRT) is essential in rectal cancer staging and treatment planning. However, when predicting the pathologic complete response (pCR) after nCRT for rectal cancer, existing works either rely on simple quantitative evaluation based on radiomics features or partially analyze multi-parametric MRI. We propose an effective pCR prediction method based on novel multi-parametric MRI embedding. We first seek to extract volumetric features of tumors that can be found only by analyzing multiple MRI sequences jointly. Specifically, we encapsulate multiple MRI sequences into multi-sequence fusion images (MSFI) and generate MSFI embedding. We merge radiomics features, which capture important characteristics of tumors, with MSFI embedding to generate multi-parametric MRI embedding and then use it to predict pCR using a random forest classifier. Our extensive experiments demonstrate that using all given MRI sequences is the most effective regardless of the dimension reduction method. The proposed method outperformed any variants with different combinations of feature vectors and dimension reduction methods or different classification models. Comparative experiments demonstrate that it outperformed four competing baselines in terms of the AUC and F1-score. We use MRI sequences from 912 patients with rectal cancer, a much larger sample than in any existing work.

Evaluation and Predictive Factors of Complete Response in Rectal Cancer after Neoadjuvant Chemoradiation Therapy

The response to neoadjuvant chemoradiation therapy is an important prognostic factor for locally advanced rectal cancer. Although the majority of the patients after neoadjuvant therapy are referred to following surgery, the clinical data show that complete clinical or pathological response is found in a significant proportion of the patients. Diagnostic accuracy of confirming the complete response has a crucial role in further management of a rectal cancer patient. As the rate of clinical complete response, unfortunately, is not always consistent with pathological complete response, accurate diagnostic parameters and predictive markers of tumor response may help to guide more personalized treatment strategies and identify potential candidates for nonoperative management more safely. The management of complete response demands interdisciplinary collaboration including oncologists, radiotherapists, radiologists, pathologists, endoscopists and surgeons, because the absence of a multidisciplinary approach may compromise the oncological outcome. Prediction and improvement of rectal cancer response to neoadjuvant therapy is still an active and challenging field of further research. This literature review is summarizing the main, currently known clinical information about the complete response that could be useful in case if encountering such condition in rectal cancer patients after neoadjuvant chemoradiation therapy, using as a source PubMed publications from 2010–2021 matching the search terms “rectal cancer”, “neoadjuvant therapy” and “response”.

MRI evaluation of the neoadjuvant chemoradiation therapy result in a patient with rectal cancer, supplemented with T2-WI texture analysis of the tumor: a clinical case

The article presents a clinical case of using the active follow-up strategy (the so-called watch wait) in a 73-year-old patient with cancer of the lower rectum with a good response to neoadjuvant chemoradiation therapy (NCRT). After 3 years of regular follow-up, including digital rectal examination, rectoscopy and MRI, indicating the absence of tumor progression, PET/ CT with 18F-FDG was obtained, which revealed a region of hypermetabolic activity in the lower rectum (SUVmax 27.1), in connection with which it was decided to carry out surgical treatment. When discussing the issue of the volume of the operation, MRI data were taken into account, supplemented by the results of T2-weighted texture analysis, which confirmed the absence of progression. The patient underwent organ-preserving treatment in the amount of transanal tumor resection. Pathomorphological examination after surgery established the inflammatory changes in the intestinal wall and absence of tumor. This case demonstrates the effectiveness of the standard examination volume when using the watch wait strategy and the possibility of using T2-WI texture analysis to increase the reliability of MRI assessment of tumor response to chemotherapy.