Primary Tumor Foci Research Articles

Choice of surgical treatment approach in patients with metastatic colorectal cancer complicated by intestinal obstruction

BACKGROUND: Every year more than 1 million new cases of colorectal cancer are diagnosed worldwide, with approximately 30% patients already having distant metastases. Colorectal cancer is often complicated, which makes chemotherapy challenging or, in some cases, impossible, therefore worsening the prognosis. As the first step, such patients need to undergo surgical treatment, in order to eliminate existing complications. However, what volume of surgery remains a discussion point among ongologists: a colostomy or a cytoreductive r2 resection to remove the primary tumor. AIM: To analyze the results of complex treatment in patients with metastatic colorectal cancer and to optimize surgical treatment approaches. MATERIALS AND METHODS: We conducted a study in Samara regional clinical Oncology dispensary (Samara, Russia), which included patients with metastatic colorectal cancer complicated by intestinal obstruction. Before treatment, all patients were examined according with current clinical standards. Subsequently, the patients were divided into two groups: the first group included patients who underwent cytoreductive surgery (r2 resection to remove the primary lesion due to the presence of colonic obstruction), and the second group included patients who underwent palliative surgery (colostomy or a bypass anastomosis in order to eliminate intestinal obstruction without removing the primary tumor). RESULTS: We found that postoperative complications in patients who had undergone primary tumor removal were significantly more prevalent. At the same time, however, the number of complications at the stage of chemotherapy, combined with angiogenesis inhibitor therapy, was significantly greater than in the group of patients in whom primary lesion was not removed. Complications that arose during chemotherapy affected the number of chemotherapy cycles performed. Discontinuation of chemotherapy affected event-free and overall survival. CONCLUSION: Timely identification and elimination of existing complications by removing the primary tumor focus before chemotherapy is an important component of an individual approach in order to develop treatment optimal tactics for patients with metastatic colorectal cancer.

Changes in tumor microbiome and underlying value according to response to neoadjuvan chemotherapy for in patients with gastric cancer

Objective: To investigate the relationship between efficacy of neoadjuvant chemotherapy (NACT) for gastric cancer and gastric microecology. Methods: This was a retrospective observational study using fresh frozen operative specimens. The specimens had been stored in the tumor sample bank of the Department of Gastrointestinal Surgery of the Affiliated Hospital of Qingdao University from January 2017 to January 2023 after having been collected from 31 patients with pathologically diagnosed gastric cancer who had no metastases and had received only neoadjuvant chemotherapy preoperatively. The study patients had all successfully undergone radical gastric cancer surgery. Patients with metastases or other primary tumor foci and/or had received other therapies within 1 month prior to surgery, including immunotherapy, targeted therapies and probiotics, were excluded. The tumors were graded and grouped in accordance with the 8th edition of the American Joint Committee on Cancer staging system and the Tumor Regression Grading System (TRG) of the College of American Pathologists. Those with TRG Grades 0-1, ypT0-1 and ypN0 were classified as responsive (Group R, 12 cases), whereas those with TRG Grades 2-3 and ypT2-4 or ypN+ were classified as non-responsive (Group NR, 19 cases). The fresh frozen samples were processed and analyzed using 16S rRNA sequencing. Alpha and beta diversity analyses were performed using the Q2-diversity plug-in for QIIME2 and STAMP was used to determine the default parameters and differentially enriched bacterial taxa in the two groups. High-dimensional class comparisons were performed by effect size linear discriminant analysis, and potential functional distributions of microbiomes were predicted using PICRUST2 (v2.3.0-b) software. Results: Groups R and NR did not differ significantly in sex, age, body mass index, smoking history, tumor location, cTNM stage before NACT, and neoadjuvant chemotherapy (all P>0.05), whereas tumor size and ypTNM stage after NACT differed significantly between the two groups (both P=0.001). Alpha and beta diversity analysis of the gastric microbiota did not reveal a statistically significant difference in alpha diversity between the two groups (P>0.05), whereas there was a statistically significant difference in beta diversity between the two groups (P=0.004). Four family-level bacterial taxa, namely Coriobacteriaceae, Ruminococcaceae, Veillonellaceae, and Lachnospiraceae, were enriched in the R group, whereas four bacterial taxa dominated by phylum Proteobacteria were enriched in the NR group. Metabolic pathways of various amino acids, including citric acid cycle and alanine, were found to be potentially predictive. Conclusions: There are significant differences in the abundance and composition of gastric microecology in gastric cancer patients with different responses to NACT.

WAYS TO IMPROVE THE EFFECTIVENESS OF CHEMOTHERAPY PATIENTS WITH LARYNGEAL CANCER, WITH MALIGNANT TUMORS OF THE NOSE AND PARANASAL SINUSES

At present, when planning complex treatment of patients with¬malignant tumors, an increasing role is given to chemotherapy. More than 50 antitumor chemotherapy drugs are used in clinical practice¬. This is due to the fact that neoplasms¬of different localization have different sensitivity to drugs. It was also found that they differ in their sensitivity to antitumor cytostatic agents in the same localization, prevalence, and histological structure¬. If the primary tumor focus in the head and neck area and metastases to regional lymph nodes, depending on the stage, can often be eliminated by radiation, surgical or combined treatment, then stable and long-term remission¬is ensured by the use of adjuvant chemotherapy.

Prediction of radiation complications by determining the blood oxidation processes in cervical cancer patients under chemoradiotherapy

Background. Radiotherapy (RT) is one of the principal methods in cancer management, and its administration in oncology practice is much wider nowadays because of the increased incidence of newly diagnosed cancer cases with wide spread and aggressive course of tumor process, and also in view of organ-sparing strategies in the combined treatment. However, the radiation reactions, especially local ones in rectum or bladder, can’t be completely avoided even using the most advanced radiotherapy facilities and dosimetry planning. Therefore, at present time not only technical modernization, but also the progress in radiobiology should be considered. Given the cytotoxic properties of some anticancer drugs, they are used in the combined therapy of cervical cancer (CC) to receive a radiosensitizing effect on the malignant cells. In particular, cisplatin inhibits reparative processes by affecting the enzymes involved in restoring the integrity of DNA or chromosome structure. Administration of the combined radiation and chemotherapy leads not only to an increase in the percentage of tumor regression, but also to an increase in the number of radiation injuries to healthy tissues. Therefore, prediction of such injuries, research and development of means of their prevention and treatment in the regimen of chemoradiotherapy (ChRT) of CC is extremely urgent and remains an unsolved problem to date. Purpose. Development of personalized approaches in ChRT in CC patients by studying its efficiency, assessing its toxicity, and predicting radiation injuries according to the data of blood oxidative processes in patients. Materials and methods. The combined radiotherapy (CRT) and ChRT were administered to the stage IIB–IIIB CC (T2b-3bN0-1M0) patients (n = 105) at the National Cancer Institute. Patients aged 25–75 years were divided into two groups: the study group and the comparison group. Complex clinical examination was conducted prior to treatment featuring the assay of tumor parameters, state of «critical organs». At the stage I of CRT regimen, conformal irradiation on pelvis minor was delivered at the electron linear accelerator «Clinac 2100 CD» with an energy of 6 MeV per area of pelvis minor with single radiation dose (SRD) of 2.0 Gy and total radiation dose (TRD) of up to 46 Gy. Patients in the study group received the CRT along with administration of chemoradiomodifying agent cisplatin 40 mg/m2 once a week intravenously (drip-feed), patients in the comparison group received no radiomodifier. At the stage II of CRT regimen, an intracavitary brachytherapy (ICBT) was administered to the CC patients at the gamma therapy equipment «AGAT-VU» using 60Co (high dose rate – HDR) sources in the mode of SRD of 5 Gy 2 times a week, 7–8 fractions, and TRD of 35–40 Gy at p. A. The TRD in total was 77–89 Gy at the p. A and 54–60 Gy at p. B. Administration of cisplatin 40 mg/m2 at the stage II of CRT was continued in the study group once a week intravenously (drip-feed), total dose of up to 200–300 mg. Radiobiological studies were performed on the peripheral blood samples from the CC patients (n = 39) before and after ChRT. The control group consisted of healthy women of the appropriate age. Blood was sampled into the special 6 ml Vacutainer type tubes with an anticoagulant according to the manufacturer’s instructions (BioReagent). Intensity of generation of О• 2– in PBL was evaluated by the chemiluminescence method using the lucigenin indicator, which, as a result of reacting with О• 2–, emits light quanta recorded by the device. Measurements were carried out on the AutoLumat LB 953 device (Germany) with appropriate corrections made to the methodology. Results and discussion. Effectiveness of CRT in CC patients was evaluated according to regression of the primary tumor focus (clinical, ultrasound, MRI or SCT data) and presence/absence of toxic manifestations of treatment following the criteria for evaluating the solid tumors regression according to the Response Evaluation Criteria in Solid Tumor (RECIST). Conclusions. The results of the study indicate that chemoradiotherapy contributes to pronounced regression of cervical tumors and does not increase toxicity of treatment due to timely correction of complications.

Radioisotope diagnostics of endogenous ACTH-dependent hypercorticism: a review

INTRODUCTION: The literature review presents the possibilities of existing methods of radionuclide diagnosis of endogenous ACTH-dependent hypercorticism, which includes Itsenko-Cushing’s disease and ectopic ACTH syndrome. The similar clinical picture of these pathologies significantly complicates their differential diagnosis. Localization of corticotropinoma, especially in patients with persistent Cushing’s disease, and ectopic focus of ACTH hyperproduction also causes difficulties.OBJECTIVE: To analyze the available foreign and domestic literature to determine the possibilities of radionuclide imaging methods in the diagnosis of endogenous ACTH-dependent hypercorticism.MATERIALS AND METHODS: A search of scientifiс publications and clinical recommendations in the information and analytical systems PudMed and elibrary over the past twenty years, dedicated to the diagnosis of Itsenko-Cushing’s disease and ectopic ACTH syndrome using radioisotope diagnostic methods by keywords «Itsenko-Cushing’s disease», «ectopic ACTH syndrome», «radionuclide diagnostics», «scintigraphy», «SPECT», «PET».RESULTS: The presented review demonstrated the broad possibilities and prospects of using modern radioisotope imaging methods in the diagnosis of endogenous ACTH-dependent hypercorticism. Radionuclide imaging methods make it possible to conduct a study in the «whole body» mode, which makes it possible to detect not only the primary tumor focus, but also metastases in patients with ectopic ACTH syndrome in one study. In addition, the use of scintigraphy or positron emission tomography with labeled somatostatin analogues makes it possible to predict the effectiveness of treatment of formations producing adrenocorticotropic hormone with somatostatin analogues, which is important when planning antitumor therapy.CONCLUSION: The use of radioisotope diagnostic methods significantly increases the accuracy of topical diagnosis of a tumor focus, allows for an assessment of the prevalence of the tumor process and the selection of patients for antitumor therapy using somatostatin analogues.

PET/CT with <sup>18</sup>F-Fluoroestradiol in First Diagnosed Breast Cancer. A Pilot Study

Purpose: To evaluate the informativity of PET/CT with 18F-FES in determining estrogen receptor (ER) positivity in breast tumor tissue, as well as in regional lymph nodes or distant metastatic foci. Material and methods: The data of 30 patients who underwent PET/CT with 18F-FES performed at the stage of primary diagnosis were retrospectively analyzed. The study included patients before the start of specific treatment or on the background of neoadjuvant hormone therapy, with previously determined expression of ER according to the results of IGC. 14 patients underwent 18F-FDG PET/CT with 2–7 days difference between both PET/CT. Results: In our study, the mean SUVmax value in the primary tumor focus was 4.8, the lowest SUVmax = 1.61, and the highest SUVmax = 18.86. 18F-FES accumulation considered suspicious for metastatic lesion in axillary lymph nodes on the affected side was detected in 16 patients (56 %), mean SUVmax = 5.2, lowest SUVmax = 0.99, highest SUVmax = 11.54. On subsequent histological examination, tumor changes in axillary lymph nodes were confirmed in 16/16 patients. Conclusion: PET/CT with 18F-FES is a diagnostic method for noninvasive evaluation of ER expression in tumor foci, which can complement the data of traditional diagnostic methods and has a significant clinical potential. In our study, the results of PET/CT with 18F-FES coincided with the data of immunohistochemical study in 100 % of cases.

Integrated Genomic Analysis of Primary Prostate Tumor Foci and Corresponding Lymph Node Metastases Identifies Mutations and Pathways Associated with Metastasis

Prostate cancer is a highly heterogeneous disease and mortality is mainly due to metastases but the initial steps of metastasis have not been well characterized. We have performed integrative whole exome sequencing and transcriptome analysis of primary prostate tumor foci and corresponding lymph node metastases (LNM) from 43 patients enrolled in clinical trial. We present evidence that, while there are some cases of clonally independent primary tumor foci, 87% of primary tumor foci and metastases are descended from a common ancestor. We demonstrate that genes related to oxidative phosphorylation are upregulated in LNM and in African-American patients relative to White patients. We further show that mutations in TP53, FLT4, EYA1, NCOR2, CSMD3, and PCDH15 are enriched in prostate cancer metastases. These findings were validated in a meta-analysis of 3929 primary tumors and 2721 metastases and reveal a pattern of molecular alterations underlying the pathology of metastatic prostate cancer. We show that LNM contain multiple subclones that are already present in primary tumor foci. We observed enrichment of mutations in several genes including understudied genes such as EYA1, CSMD3, FLT4, NCOR2, and PCDH15 and found that mutations in EYA1 and CSMD3 are associated with a poor outcome in prostate cancer.

Resection of giant sigmoid cancer metastasis in the skull bone with extra-, intracranial distribution

The most common secondary target organs in patients with colorectal cancer are the liver and lungs. Cranial metastases from sigmoid colon cancer are rare. Giant cranial metastases are currently diagnosed in exceptional cases.The article presents a clinical case of a secondary extra‑intracranial lesion with a stable primary tumor focus in the sigmoid colon in a young patient with a high functional status.

THU483 Role Of Excess GH On Breast Cancer Aggressiveness And Metastasis In Acromegaly

Abstract Disclosure: J. Oh: None. C. Kang: None. E. Wang: None. S. Lee: None. J. Nam: None. C. Ku: None. E. Lee: None. Introduction Acromegaly is a rare disease characterized by chronic growth hormone (GH) and insulin-like growth factor-1 hypersecretion. In previous studies, it is known that the incidence of breast cancer increases in patients with acromegaly. For breast cancers, autocrine GH and GHR are expressed in primary lesion, which is significantly increased in metastatic one. To date, however, the precise mechanism of endocrine GH in breast cancer metastasis has not been defined. This study aimed to investigate the role of endocrine excess GH facilitating breast cancer metastasis in acromegaly mice model. Method We used Aiplox/lox (Con) and rGHp-Cretg/+; Aiplox/lox mice (Acro), which was previously established to model the phenotype of human acromegaly. To generate orthotopic xenograft model, we used C57BL/6 female mouse derived breast cancer cell line Py230 cells. Py230 cells were injected into mammary gland and tumor volumes were measured every 2 days. Tumor growth and metastasis were confirmed by bioluminescent in vivo imaging system (IVIS). Also, we investigated the effects of GH on triple negative breast cancer cell lines, which have the higher expression of GHR. To define GH induced pathway, we performed RT2 array. Cell proliferation was investigated with MTT assay and cell migration was investigated with wound healing assay and transwell invasion assay. Results In mouse orthotopic xenograft studies, tumor volumes of Acro mice were higher than that of Con mice (increase of 310%, 846.04±290.7 vs. 205.97±33.7 mm3, p=0.001). The tumor volume and serum GH level showed positive correlation (R2= 0.4739, p=0.027). After 14 weeks, the Acro mice showed significantly increased bioluminescence activity in the lung (increase of 1023%, 494666.7±104668.2 vs. 44037.7±6641.9 AU, p=0.0127). When GHR antagonist was treated, tumor growth and lung metastasis were decreased. We excised primary tumor and lung metastatic foci and performed RT2 array. We found Tcf-20 gene, which is upregulated in both primary tumor and lung metastatic burden (increase of 216%, p=0.0153). We confirmed GH induced Tcf-20 gene induction (increase of 57% (p=0.043), 41% (p=0.05), 67% (p=0.0021) in Hs578T, Py230 (p=0.05), and Hcc1806 cells each). We knocked down Ghr or Tcf-20 genes and observed decrease of invasion and migration compared to GH treated siCON HCC1806 (decrease of 64.5% in siGHR, decrease of 83.3% in siTCF-20, compared to siCON cells, p=0.000819977) and Py230 cells (decrease of 47.3% in siGHR transfected, decrese of 49.3% in siTCF-20 transfected, compared to siCON cells, p=0.0012). Conclusion Excess GH in acromegaly possess a strong potential to promotes tumor development and metastasis. We identified a molecular mechanism by which GH-induced TCF-20 promote tumor aggression and metastasis. These findings can aid in the development of improved strategies for managing cancer in acromegalic patients. Presentation: Thursday, June 15, 2023

Effect of Differences in the Expression Levels Steroid Hormone Receptors and HER2 in the Primary Tumor and Metastatic Focus on the Efficacy of Eribulin Monotherapy in Metastatic Breast Cancer

Актуальность: На сегодняшний день очевидно, что биопсия метастатического очага является крайне важной процедурой для персонализации терапии больных метастатическим раком молочной железы (мРМЖ). Кроме этого, появляется все больше данных о предиктивной и прогностической роли дискордантности статуса экспрессии гормональных рецепторов и рецептора эпидермального фактора роста (HER2) в терапии мРМЖ. Цель исследования. Изучение влияния различий уровня экспрессии рецепторов стероидных гормонов и HER2 в первичной опухоли и метастатическом очаге на эффективность монохимиотерапии эрибулином при мРМЖ. Материалы и методы. В исследование кафедры онкологии с курсом торакальной хирургии ФПК и ППС ФГБОУ ВО КубГМУ Минздрава России были включены пациенты с мРМЖ (n = 61), которым в анамнезе назначалась монохимиотерапия эрибулином в ГБУЗ КОД № 1» МЗ КК (г. Краснодар). Клиническая информация и исходы оценены по данным медицинской документации и госпитального ракового регистра. Проанализирована роль изменения экспрессии рецепторов стероидных гормонов и HER2 в ответе на монохимиотерапию (МХТ) эрибулином. Результаты. Показано, что на МХТ эрибулином уровень экспрессии ЭР ˃ 50 % в метастазе негативно сказывается на времени без прогрессирования (ВБП) (AUC 0,762 ± 0,092, ДИ (0,586-0,891), р = 0,0044). При уровне HER2 (0) в метастазе отмечается снижение эффективности монохимиотерапии эрибулином (AUC 0,750 ± 0,144, ДИ (0,578-0,879), р = 0,0833). Риск прогрессирования снижается при экспрессии ПР ≤ 20 % (р = 0,0182, ОР 0,14 (95 % ДИ 0,03-0,72) и HER2 3+ статусе (р = 0,0128) в метастазе. Медиана ВБП при экспрессии HER2 (3+) не была достигнута, при HER2low (1+2+) составила 5 мес. и при HER2 (0) — 3 мес., (р = 0,0359, log-rank test). Модель, включающая ЭР > 90 % в первичной опухоли, ЭР > 50 %, ПР > 20 %, HER2-0/low в метастазе прогнозирует прогрессирование на МХТ эрибулином (AUC = 0,614 ± 0,092 (95 % ДИ 0,510-0,719), р = 0,0289). Таким образом, описан люминальный А HER2-негативный статус, который является неблагоприятным суррогатным фенотипом метастатического очага для назначения МХТ эрибулином. Заключение. Представленные данные продемонстрировали важную прогностическую роль дискордантности экспрессии рецепторов стероидных гормонов и HER2 между первичной опухолью и метастатическим очагом в риске прогрессирования на МХТ эрибулином. Очевидно, что биопсия метастатического очага является важным фактором, способным не только изменить тактику в отношении суррогатного подтипа метастатического очага, но и персонализировать химиотерапию у больных мРМЖ.

Abstract A046: Integrated genomic analysis of primary prostate tumor foci and corresponding lymph node metastases identifies pathways associated with metastatic disease

Abstract Background: Prostate cancer (PCa) is a highly heterogeneous disease, and mortality is mainly due to metastases. However, the molecular underpinnings that lead to the initial steps of metastasis have not been well characterized. We have performed integrative whole exome sequencing and transcriptome analysis of primary prostate tumor foci and corresponding lymph node metastases (LNM). Design: Primary tumor foci (PTF) and LNM from 40 patients with high-risk PCa were analyzed by RNAseq. Two or more PTF and all available LNM greater than 0.4cm were subjected to sequencing. Of these 40 patients, 17 (42.5%) had LNM and 23 (57.5%) had benign LNs. A total of 155 tissue samples (97 PTF, 39 benign LNs, and 19 LNM) were sequenced and mapped to the human transcriptome with STAR mapper after QC trimming and removal of adapter sequences using TrimGalore. Differentially expressed genes between PTF, LNM, and benign LNs were identified using DESeq2, and gene set enrichment analysis was performed using WebGestalt. WES data was analyzed using GATK pipelines including Mutect2 and maftools. Results: A median of 57 million paired-end reads were obtained per sample, with a median of 10 million total readcounts per sample across the transcriptome, and 39,021 transcripts were detected in at least 5% of samples. Comparing PTF to LNM, 6203 transcripts were differentially expressed (p-adj < 0.01). PTF were enriched relative to LNM in gene sets associated with Wnt signaling, hormone signaling, Hippo signaling, KRAS signaling, and the epithelial to mesenchymal transition. Comparing PTF from metastatic patients to non-metastatic patients, 1265 transcripts were differentially expressed (p-adj < 0.01). PTF from metastatic patients were enriched in gene sets associated with cell cycle progression, oxidative phosphorylation, ER stress, fatty acid metabolism, and DNA repair. LNM gene sets were enriched in endoplasmic reticulum (ER) stress and oxidative phosphorylation. The top 500 upregulated genes in malignant tissues were significantly enriched in genes related to androgen and estrogen signaling as expected. We also identified a set of 193 genes whose expression was significantly increased in primary tumor over benign LNs and in LNM over primary tumors. This gene set was significantly enriched in genes related to oxidative phosphorylation and included oncogenes such as PIK3CB, NCOA2, and SCHLAP1. Frequently mutated genes included CSMD3, FAT4, DNAH7, and KMT2C. DNA mutations associated with metastases included PCNX2. Oncogenic pathways associated with metastases in WES analysis included RAS, Notch, Wnt, Hippo, and PI3K pathways. Conclusions: Signaling pathways associated with ER stress, oxidative phosphorylation, metabolism, and cell cycle progression are prominent in LNM of aggressive PCa. PIK3CB, NCOA2, and SCHLAP1 expression are significantly increased in LNM. LNM had higher mutational burdens and were associated with hypermutability pathways, as well as mutations in RAS, Notch, Wnt, Hippo, and PI3K pathway genes. Citation Format: Carlos S. Moreno, Cynthia L. Winham, Emma R. Klein, Yijian Huang, David M. Schuster, Martin G. Sanda, Adeboye O. Osunkoya. Integrated genomic analysis of primary prostate tumor foci and corresponding lymph node metastases identifies pathways associated with metastatic disease [abstract]. In: Proceedings of the AACR Special Conference: Advances in Prostate Cancer Research; 2023 Mar 15-18; Denver, Colorado. Philadelphia (PA): AACR; Cancer Res 2023;83(11 Suppl):Abstract nr A046.

Psycho-emotional well-being of non-hodgkin lymphoma patients

The given study focuses on the evaluation of the psycho-emotional well-being of patients with non-Hodgkin’s lymphomas (NHL) according to age, gender, living environment, morphological subtype, stage, primary tumor focus, Charlson comorbiditiesindex, and completion of first-line chemotherapy treatment. To carry out the study, a number of 126 patients aged between 18 and 78 years, included in the treatment and monitored in the Department of Hematology, IMSP Oncological Institute, during the years 2020-2022, were selected. The Global Well Being (GWB) score was used to test the proposed hypotheses. The results illustrate statistically significant correlations between GWB score and gender, living environment, extranodal onset, and treatment period. The lack of statistically significant correlations was appreciated between the GWB score and age, disease stage, comorbidities.

A combination of circulating tumor cell (CTC) and cancer stem cell (CSC) markers to predict the prognosis of breast cancer.

e13007 Background: CTCs are tumor cells that shed from either primary tumor or metastatic foci and can provide more information about the tumor's biological entity than circulating tumor DNA (ctDNA), or exosomes do. The current FDA-approved CTC assay misses the CSC phenotypes, which are pivotal in driving tumorigenesis, metastasis, resistance to treatment, and cancer recurrence. Therefore, we combine CTC and CSC markers to determine the prognosis. We hypothesized that the CSC markers on CTC correlate with poorer outcomes. Methods: Peripheral blood samples of qualified breast cancer patients were collected at diagnosis and every 6 months during follow-up. EpCAM, MUC-1, and HER2 are used as CTC markers, while TWIST, AKT, PI3K, and ALDH-1 are used to detect CSC. According to the expression level of the above markers, patients were categorized into four groups: NN negative with both CTC and CSC markers, NP expressing CSC markers, PN expressing CTC markers, and PP positive with both CTC and CSC markers. The progression-free survival (PFS) and overall survival (OS) of all four groups were calculated by Kaplan-Meier model from the date of surgery until the disease progression and death/the last follow-up of the patients, respectively. Results: We screened 100 patients aged 18 years or older with confirmed stage II to stage IV breast cancer and selected 81 patients for the study. Fifteen patients dropped out of the study due to loss of follow-up or incomplete clinical information leaving 66 evaluable patients. There are 55 Caucasians (83%), 5 African Americans (7.5%), 5 Hispanics (7.5%), and 1 Asian (1.5%). The median age of the patients is 52.5 years old (29-81), and the median follow-up is 22.6 months (2.5-65). Most patients have stage III disease (60 and 91%) followed by 4 stage IV (6%) and 2 Stage II (3%). The median time between the first sample date and surgery is 172 days (-148 to 270). The NN group has the most patients (41 and 62%) compared to NP group (16 and 24%) and PN group (6 and 9%). The PP group has the least number of patients (2 and 3%) and is not observed in patients with positive hormonal receptors (HR). The PN group has a higher ratio of HR-HER2+ patients than NP group does. The HR and HER2 statuses were checked in the four groups. Interestingly, the NN and NP groups are mostly HR+HER2- patients, while the PN group is mainly HR- patients regardless of the HER2 status. The PP group only has HR- patients. The PFS curves start to flatten at 12 months and separate among the four groups, with the highest PFS percentage in the NP (81.2%) and NN (77.8%) followed by the PN (62.5%) and PP (50%) group. The OS percentage is 70% in NN, 66% in PN, 60% in NP, and 50% in PP, similar to the PFS pattern. Conclusions: Checking both CTC and CSC markers help triage the prognosis of breast cancer patients. CTC and CSC markers observed in breast cancer patients with different HR or HER2 status can be further investigated for potential correlations.

Medium-chain triglyceride-stabilized docetaxel-loaded HSA nanoparticles effectively inhibited metastatic non-small cell lung cancer.

Metastatic non-small cell lung cancer (NSCLC) is refractory with a very poor prognosis. Docetaxel (DTX) injection (Taxotere®) has been approved for the treatment of locally advanced or metastatic NSCLC. However, its clinical application is restricted by severe adverse effects and non-selective tissue distribution. In this study, we successfully developed DTX-loaded human serum albumin (HSA) nanoparticles (DNPs) with modified Nab technology, by introducing medium-chain triglyceride (MCT) as a stabilizer. The optimized formulation had a particle size of approximately 130nm and a favorable stabilization time of more than 24h. DNPs dissociated in circulation in a concentration-dependent manner and slowly released DTX. Compared with DTX injection, DNPs were more effectively taken up by NSCLC cells, thus exerting stronger inhibitory effects on their proliferation, adhesion, migration, and invasion. In addition, DNPs showed prolonged blood retention and increased tumor accumulation relative to DTX injection. Ultimately, DNPs produced more potent inhibitory effects on primary or metastatic tumor foci than DTX injections but caused markedly lower organ toxicity and hematotoxicity. Overall, these results support that DNPs hold great potential for the treatment of metastatic NSCLC in clinical.

Abstract 6081: Integrative genomic analysis of primary prostate tumors and corresponding lymph node metastases

Abstract Background: Prostate cancer (PCa) is a highly heterogeneous disease, and mortality is mainly due to metastases. However, the molecular underpinnings that lead to the initial steps of metastasis have not been well characterized. We have performed integrative whole exome sequencing and transcriptome analysis of primary prostate tumor foci and corresponding lymph node metastases (LNM). Design: Primary tumor foci (PTF) and LNM from 40 patients with high-risk PCa were analyzed by RNAseq. Two or more PTF and all available LNM greater than 0.4cm were subjected to sequencing. Of these 40 patients, 17 (42.5%) had LNM and 23 (57.5%) had benign LNs. A total of 155 tissue samples (97 PTF, 39 benign LNs, and 19 LNM) were sequenced and mapped to the human transcriptome with STAR mapper after QC trimming and removal of adapter sequences using TrimGalore. Differentially expressed genes between PTF, LNM, and benign LNs were identified using DESeq2, and gene set enrichment analysis was performed using WebGestalt. WES data was analyzed using GATK pipelines including Mutect2. Results: A median of 57 million paired-end reads were obtained per sample, with a median of 10 million total readcounts per sample across the transcriptome, and 39,021 transcripts were detected in at least 5% of samples. Comparing PTF to LNM, 6203 transcripts were differentially expressed (p-adj < 0.01). PTF were enriched relative to LNM in gene sets associated with Wnt signaling, hormone signaling, Hippo signaling, KRAS signaling, and the epithelial to mesenchymal transition. Comparing PTF from metastatic patients to non-metastatic patients, 1265 transcripts were differentially expressed (p-adj < 0.01). PTF from metastatic patients were enriched in gene sets associated with cell cycle progression, oxidative phosphorylation, ER stress, fatty acid metabolism, and DNA repair. LNM gene sets were enriched in endoplasmic reticulum (ER) stress and oxidative phosphorylation. The top 500 upregulated genes in malignant tissues were significantly enriched in genes related to androgen and estrogen signaling as expected. We also identified a set of 193 genes whose expression was significantly increased in primary tumor over benign LNs and in LNM over primary tumors. This gene set was significantly enriched in genes related to oxidative phosphorylation and included oncogenes such as PIK3CB, NCOA2, and SCHLAP1. Integrative RNAseq analyses with WES will be discussed. Conclusions: Signaling pathways associated with ER stress, oxidative phosphorylation, metabolism, and cell cycle progression are prominent in LNM of aggressive PCa. PIK3CB, NCOA2, and SCHLAP1 expression are significantly increased in LNM. Citation Format: Carlos S. Moreno, Cynthia L. Winham, Emma R. Klein, Yijian Huang, David M. Schuster, Martin G. Sanda, Adeboye O. Osunkoya. Integrative genomic analysis of primary prostate tumors and corresponding lymph node metastases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6081.

Molecular genetic sequencing of neuroendocrine tumors of the gastrointestinal tract.

651 Background: The objective of this work was to evaluate the molecular and genetic features of the NET gastrointestinal tract. Genomic sequencing of 30 tumor samples of the latest generation was carried out and the data obtained were evaluated. Methods: In total, 30 tumor blocks of patients with gastrointestinal NET were tested by the new generation sequencing (NGS) method. The following genes were analyzed: ATM, ATR, BARD1, BRCA1, BRCA2, BRIP1, CDH1, CDK12, CHEK1, CHEK2, EPCAM, FANCL, MLH1, MSH2, NBN, NF1, PALB2, PMS2, RAD51B, RAD51C, RAD51D, RAD54L, STK11, TP53, POLE, KRAS, NRAS, BRAF, EGFR, ERBB2, PIK3CA, MET ex14, BAT25, BAT26, NR21, NR24, MONO27, KIT, PDGFRA, Pi3Ca. Preparation of libraries for sequencing was carried out using NimblGen SepCapEZ Choice. Sequencing was performed on the Illumina MiSeq device. Results: In the study cohort of patients whose tumor blocks were sent for examination by the NGS method, there were more women – 19 (63.3%) than men – 11 (36.7%). When analyzing the age of patients, it should be noted that among all age groups, elderly patients predominated (60-74 years according to the WHO classification, 2016) – 12 (40%). In the majority of patients – 10 (33.3%) – the primary tumor focus was localized in the pancreas, in 6 (20%) patients it was primarily affected stomach, 7 (23.3%) – small intestine. Other parts of the gastrointestinal tract were affected much less frequently: the colon – in 1 (3.3%) patients. According to the division according to the degree of differentiation of gastrointestinal NET10 tumors had a degree of differentiation G1 (33.3%), 16 -G3 (54.3%), 4– G3 (13.3%). In the tumor sample of a patient with gastric NET G1 (Ki 67 = 2%), POLE mutations were found: c.2276G > A, p.R759H and CHEK2: c.470T > C, p.I157T. Also, mutations MLH1: c.199G > A, p.G67R BRCA1: c.1881 were found in the tumor sample of another patient with gastric NET G2 (Ki 67 = 7%). Conclusions: To improve the survival rates of patients, it is worth paying special attention to the molecular genetic study of the NET gastrointestinal tract. It is molecular genetic profiling that can become the basis for building more individualized algorithms for treating patients. The results of this study allow us to count on the fact that when conducting a study on a larger cohort of patients with gastrointestinal NET, it is possible to obtain results that will expand our knowledge of this nosology and allow us to supplement the already available information about prognosis factors and predictors of response to treatment.

STRUCTURAL ORGANIZATION OF COLLAGEN-CONTAINING CONNECTIVE TISSUE AS A PREDICTOR OF METASTATIC PROGRESSION OF PROSTATE CANCER

Summary. Aim: to determine at the optical level the role of the fibrillar organization of the collagen-containing connective tissue component of the primary tumor focus in prostate cancer (PCa) progression. Objects and methods: the morphological study is based on the analysis of the histological material of the primary tumor foci of 55 PCa patients without tumor progression in the postoperative period and bone metastases. The tumors were graded Gleason 6–9 at surgery. The features of the architecture of collagen-containing connective tissue in tumors were determined in histological slides stained by Van-Gieson. Results: the remodeling of the collagen-containing stromal component located both around the glandular structures (increase in the percentage of straight and aligned collagen fibers compared to the curved ones) and in the stroma itself has been found. Such remodeling is manifested by an increase in the total mass of fibrous structures, an increase in the width of collagen fibrils, their compaction in relation to the density of their location, peculiarities of desmoplasia, alignment and elongation. The specified features are consistent with the Gleason score and the postoperative disease course, namely, the occurrence of metastases. Conclusions: the desmoplastically changed collagen-containing connective tissue component of the PCa creates favorable conditions for the unimpeded migration and realization of the invasive potential of cancer cells, in particular those expressing bone tissue remodeling proteins.

Significance and possible causes of hormone receptor expression loss in metastatic breast cancer. Phenotypic evolution of luminal <i>BRCA1</i>-associated breast cancer to triple negative subtype in lung metastasis and PARP inhibition strategy in early-line therapy

Current clinical recommendations indicate the need for a biopsy of a metastatic focus in metastatic breast cancer (BC), but the optimal frequency of additional molecular analysis remains unclear. The discordance of hormonal receptors (HR) between the primary tumor and metastatic foci has prognostic significance, while the transition from HR-positive BC to a triple negative phenotype is associated with a worse clinical prognosis. Acquisition of HR expression in primary triple negative BC is more favorable due to the wide range of options for HR-positive BC treatment. Over the past few years, PARP inhibitors have become an important therapeutic option for the treatment of various tumor types, including BC and luminal surrogate subtypes. However, some questions still remain unresolved, the most important of which are: what is the optimal sequence of the use of CDK4 / 6 inhibitors as part of combined hormone therapy and PARP inhibitors in luminal types of BRCA-associated BC and how effective is the strategy of PARP inhibition after the use of combined hormone therapy with CDK4 / 6 inhibitors? It is obvious that the answers to the questions can be partially obtained by performing a biopsy of the most clinically significant metastatic focus and selecting therapy according to the phenotypic surrogate subtype. A clinical case of the phenotypic evolution of HR-positive BRCA1-associated BC into a triple negative phenotype during metastasis to the lungs and the luminal phenotype of tumor metastasis in soft tissues is presented. Biopsy of the most clinically significant metastatic lesion in the lungs in this case changed the strategy of early-line therapy for estrogen-receptor-positive disease, when in the absence of a biopsy, a combined hormone therapy regimen with CDK4 / 6 inhibitors could be applied. At the same time, the strategy of using PARP inhibitor talazoparib, which has shown efficacy in all surrogate subtypes, should certainly be prescribed in the early line of therapy for BRCA-associated disease with loss of estrogen receptor expression. Despite the luminal phenotype of metastasis in the soft tissues of the back and the unknown status of bone metastases, the drug demonstrates efficacy in these cases as well. It should be noted that partial response according on RECIST 1.1 months with an improvement in the quality of life and the disappearance of pain syndrome was evaluated after 10 weeks of treatment. The response duration was an unprecedented 10 months.

Metastatic multiple gastric neuroendocrine tumors with a long history of proton pump inhibitor use: A case report

It is widely accepted that gastric neuroendocrine tumors (NETs) develop due to enterochromaffin-like (ECL) cell proliferation following exposure to hypergastrinemia, which causes hyperplastic-dysplastic-neoplastic changes. Here we describe the case of a 46-year-old female patient diagnosed with metastatic NETs by liver biopsy and evaluated at an external center. At our hospital, nodular structures extending from the cardia to the antrum were observed by gastroscopy, considered the primary tumor focus. Histopathological examination revealed a trabecular-insular pattern, with microNETs consisting of monotone cells with round-oval nuclei and surrounding neuroendocrine cell hyperplasia foci and fundic gland polyps. The patient had a history of regular proton pump inhibitor (PPI) use for 10 years and a serum gastrin of 9240 pg/mL. A 3-cm metastatic lesion in the left lobe of the liver was observed in whole-body imaging with octreotide. By gastrectomy, we observed a large number of nodular lesions in the corpus-antrum and a 3-cm diameter lesion in the hepatectomy material. Histopathological examination revealed NETs in multiple foci with submucosal invasion in the stomach. The Ki-67 proliferative index was 3%. Metastatic tumors of similar morphology were found in the liver and three of the greater curvature lymph nodes. We made a diagnosis of multiple gastric NETs (Grade 2). In Type I gastric NETs, the neuroendocrine cell proliferation spectrum up to NET is observed as a result of hypergastrinemia due to atrophic gastritis. Also, in experimental studies, prolonged hypergastrinemia has been reported to cause ECL cell neoplasms in animals treated with PPIs. Although our case could be accepted as Type 1 NET, the possibility of developing NET secondary to long-term PPI use should also be considered.

Analysis of the Results of Proton Radiation Therapy of Patients with Squamous Cell Carcinoma of the Head and Neck

Purpose: To evaluate the severity of early radiation reactions and the first results of proton therapy treatment of patients with squamous cell carcinoma of the head and neck. Material and methods: From January 2019 to March 2022, more than 1 400 patients received proton therapy on the proton-cyclotron complex ProteusPlus235. The search for patients was carried out in the database of patients who received proton radiation therapy for oncological diseases in the FMBA system of Russia. The study included 62 patients with confirmed squamous cell carcinoma and the unifying model was: proton therapy in the mode of five-day fractionation of SFD 2 Gr, TFD 50 Gy for locoregional lymphatic collector zones and TFD 60–70 Gy for the area of the primary tumor focus and high-risk zones. The age group is from 18 to 78 years. According to the classification of ICD10 — 35 patients were diagnosed with C00–C14 “Malignant neoplasms of the lip, oral cavity and pharynx” (56,4 %), 27 patients with C30–C32 “Malignant neoplasms of the upper respiratory organs” (43,5 %). Results: The assessment of long-term treatment results and the severity of radiation complications requires a systematic and uniform approach and is the subject of further research, along with the development of optimal patient models for treatment by proton pencil-beam scanning therapy. Conclusions: Proton beam and proton chemoradiotherapy have demonstrated decreasing trends or comparable frequency and severity of radiation reactions compared to photon therapy. In this regard, the decision to choose a treatment method should be based on an assessment of clinical efficacy, relapse-free and event-free survival, which is the subject of further scientific research.