In patients with well-differentiated neuroendocrine tumours, there is no apparent benefit of somatostatin analogues after disease control by peptide receptor radionuclide therapy.

PURPOSE: Peptide receptor radionuclide therapy (PRRT) and somatostatin analogues (SSAs) are commonly combined as primary treatment for neuroendocrine neoplasms (NEN), and SSAs given as maintenance. We sought to evaluate whether sequential therapy with PRRT followed by SSAs has progression or survival benefits in patients with NEN after disease control by PRRT. METHODS: This prospective, randomised, single-centre study had as principal eligibility criteria: unresectable, locally advanced, or metastatic, histologically confirmed well-differentiated NEN; no symptoms/biochemical diagnosis of carcinoid syndrome; no SSAs or ≤ 3 months of SSAs before PRRT; and stable disease or partial or complete response after PRRT. Altogether, 115 patients were randomised 2:1 to an SSA group (n = 74) given octreotide acetate LAR every 4 weeks, or a control group (n = 41) receiving only best supportive care. Octreotide treatment was to stop upon intolerable toxicity or patient refusal, or, at physician/patient discretion, upon NEN progression. The primary endpoint was progression-free survival (PFS), the secondary endpoint, and overall survival (OS). RESULTS: Median (25th-75th percentile) follow-up from the first PRRT activity to death or latest observation was 6.6 (3.18-10.22) years. During that time, 71/115 patients (62%) progressed, 52/74 (70%) in the SSA group, and 19/41 (46%) in the control group (p = 0.01). Eighty-eight/115 patients (76%) died, 58/74 (78%) in the SSA group, and 30/41 (73%) in the control group (p = 0.52). Median (95% CI) PFS was 4.7 (2.8-7.7) years in the SSA group, and 6.4 (4.1-not reached) years in controls. Overall, median OS was 6.6 years. Neither PFS nor OS differed between groups (p = 0.129, p = 0.985, respectively). CONCLUSIONS: In patients with disease control after PRRT, subsequent SSA treatment appeared not to be associated with better PFS or OS. Whether to continue SSA administration upon progression after PRRT requires evaluation in a prospective, randomised, controlled multicentre study with a relatively homogeneous sample.

Differences in Gene Expression Profile of Primary Tumors in Metastatic and Non-Metastatic Papillary Thyroid Carcinoma-Do They Exist?

Molecular mechanisms of distant metastases (M1) in papillary thyroid cancer (PTC) are poorly understood. We attempted to analyze the gene expression profile in PTC primary tumors to seek the genes associated with M1 status and characterize their molecular function. One hundred and twenty-three patients, including 36 M1 cases, were subjected to transcriptome oligonucleotide microarray analyses: (set A-U133, set B-HG 1.0 ST) at transcript and gene group level (limma, gene set enrichment analysis (GSEA)). An additional independent set of 63 PTCs, including 9 M1 cases, was used to validate results by qPCR. The analysis on dataset A detected eleven transcripts showing significant differences in expression between metastatic and non-metastatic PTC. These genes were validated on microarray dataset B. The differential expression was positively confirmed for only two genes: IGFBP3, (most significant) and ECM1. However, when analyzed on an independent dataset by qPCR, the IGFBP3 gene showed no differences in expression. Gene group analysis showed differences mainly among immune-related transcripts, indicating the potential influence of tumor immune infiltration or signal within the primary tumor. The differences in gene expression profile between metastatic and non-metastatic PTC, if they exist, are subtle and potentially detectable only in large datasets.

EANM guidelines for radionuclide therapy of bone metastases with beta-emitting radionuclides.

The skeleton is the most common metastatic site in patients with advanced cancer. Pain is a major healthcare problem in patients with bone metastases. Bone-seeking radionuclides that selectively accumulate in the bone are used to treat cancer-induced bone pain and to prolong survival in selected groups of cancer patients. The goals of these guidelines are to assist nuclear medicine practitioners in: (a) evaluating patients who might be candidates for radionuclide treatment of bone metastases using beta-emitting radionuclides such as strontium-89 (89Sr), samarium-153 (153Sm) lexidronam (153Sm-EDTMP), and phosphorus-32 (32P) sodium phosphate; (b) performing the treatments; and

EANM guideline for radionuclide therapy with radium-223 of metastatic castration-resistant prostate cancer.

Radium Ra-223 dichloride (radium-223, Xofigo®) is a targeted alpha therapy approved for the treatment of castration-resistant prostate cancer (CRPC) with symptomatic bone metastases and no known visceral metastatic disease. Radium-223 is the first targeted alpha therapy in this indication providing a new treatment option, with evidence of a significant survival benefit, both in overall survival and in the time to the first symptomatic skeletal-related event. The skeleton is the most common metastatic site in patients with advanced prostate cancer. Bone metastases are a clinically significant cause of morbidity and mortality, often resulting in bone pain, pathologic fracture, or spinal cord compression necessitating treatment. Radium-223 is selectively accumulated in the bone, specifically in areas of high bone turnover, by forming complexes with the mineral hydroxyapatite (the inorganic matrix of the bone). The alpha radiation generated during the radioactive decay of radium-223 produces a palliative anti-tumour effect on the bone metastases. The purpose of this guideline is to assist nuclear medicine specialists in evaluating patients who might be candidates for treatment using radium-223, planning and performing this treatment, understanding and evaluating its consequences, and improving patient management during therapy and follow-up.

Coexistence of TERT Promoter Mutations and the BRAF V600E Alteration and Its Impact on Histopathological Features of Papillary Thyroid Carcinoma in a Selected Series of Polish Patients.

TERT promoter (TERTp) mutations are important factors in papillary thyroid carcinomas (PTCs). They are associated with tumor aggressiveness, recurrence, and disease-specific mortality and their use in risk stratification of PTC patients has been proposed. In this study we investigated the prevalence of TERTp mutations in a cohort of Polish patients with PTCs and the association of these mutations with histopathological factors, particularly in coexistence with the BRAF V600E mutation. A total of 189 consecutive PTC specimens with known BRAF mutational status were evaluated. TERTp mutations were detected in 8.5% of cases (16/189) with the C228T mutation being the most frequent. In six of the PTC specimens (3.2%), four additional TERTp alterations were found, which included one known polymorphism (rs2735943) and three previously unreported alterations. The association analysis revealed that the TERTp hotspot mutations were highly correlated with the presence of the BRAF V600E mutation and their coexistence was significantly associated with gender, advanced patient age, advanced disease stage, presence of lymph node metastases, larger tumor size, and tumor-capsule infiltration. While correlations were identified, the possibility of TERTp mutations being key molecular modulators responsible for PTC aggressiveness requires further studies.

Gene signature of the post-Chernobyl papillary thyroid cancer.

PURPOSE: Following the nuclear accidents in Chernobyl and later in Fukushima, the nuclear community has been faced with important issues concerning how to search for and diagnose biological consequences of low-dose internal radiation contamination. Although after the Chernobyl accident an increase in childhood papillary thyroid cancer (PTC) was observed, it is still not clear whether the molecular biology of PTCs associated with low-dose radiation exposure differs from that of sporadic PTC. METHODS: We investigated tissue samples from 65 children/young adults with PTC using DNA microarray (Affymetrix, Human Genome U133 2.0 Plus) with the aim of identifying molecular differences between radiation-induced (exposed to Chernobyl radiation, ECR) and sporadic PTC. All participants were resident in the same region so that confounding factors related to genetics or environment were minimized. RESULTS: There were small but significant differences in the gene expression profiles between ECR and non-ECR PTC (global test, p < 0.01), with 300 differently expressed probe sets (p < 0.001) corresponding to 239 genes. Multifactorial analysis of variance showed that besides radiation exposure history, the BRAF mutation exhibited independent effects on the PTC expression profile; the histological subset and patient age at diagnosis had negligible effects. Ten genes (PPME1, HDAC11, SOCS7, CIC, THRA, ERBB2, PPP1R9A, HDGF, RAD51AP1, and CDK1) from the 19 investigated with quantitative RT-PCR were confirmed as being associated with radiation exposure in an independent, validation set of samples. CONCLUSION: Significant, but subtle, differences in gene expression in the post-Chernobyl PTC are associated with previous low-dose radiation exposure.

Stereotactic Body Radiation Therapy for Symptomatic Pancreatic Insulinoma: Two-Case Report and Literature Review.

Insulinoma is the most common functional neuroendocrine tumor of the pancreas, with the main clinical symptom being hypoglycemia. The standard treatment is surgery, but some patients are not eligible for surgery, while in those operated on, the risk of perioperative complications is up to 30%. Diazoxide treatment to prevent hypoglycemia is effective only in 50% of patients. To prevent tumor growth and hormonal excess, stereotactic radiotherapy may be an alternative to surgical treatment. In our paper, we present two cases of patients with insulinoma treated successfully with stereotactic body radiation therapy (SBRT).

Changing Clinical Presentation of Pediatric Differentiated Thyroid Cancer in Poland: A Retrospective Cohort Study Spanning 45 Years.

Background: Differentiated thyroid carcinoma (DTC) in children is uncommon; clinical presentation over recent decades is incompletely characterized. Methods: This retrospective cohort study analyzed demographic and disease characteristics of consecutive juveniles with DTC treated from 1970 to 2015 at Poland's largest pediatric DTC referral center, Maria Sklodowska-Curie National Research Institute of Oncology, Gliwice, who had available records. Sex, age, histopathological characteristics, and DTC stage were documented. We aimed to identify changes in these variables over time and independent risk factors for lymph node or distant metastases. Trends in these variables were assessed using the Cochran-Armitage test and Spearman correlation. Multivariable logistic regression was performed to identify risk factors associated with lymph node or distant metastases. Results: 475 of 479 patients (99.2%) were included in the analysis; roughly half were age ≥15 years, 10%, <10 years. Papillary thyroid carcinoma (PTC) represented 88% of cases and follicular thyroid carcinoma (FTC) 11%. Tumors ≤2 cm constituted 56% of cases with relevant data; those >4 cm accounted for 12%. Multifocality was observed in 37% and extrathyroidal invasion in 22%. Lymph node metastases were noted in 59% and distant metastases in 16%. Over the observation period, significant trends among new cases included: increased proportion of adolescents >15 years; increased frequency of tumors ≤2 cm, decreased multifocality rates, and increased proportion of PTC versus FTC. Extrathyroidal invasion rates remained appreciable throughout, ranging from 17 to 28% during the 5-year study subperiods after 1990. Lymph node metastases significantly increased in frequency in the central neck, remaining consistently common in lateral sites; presence of distant metastases significantly decreased. In multivariable analysis, multifocality, extrathyroidal invasion, and tumor size were independently associated with lateral lymph node metastases and multifocality, larger tumor size, and N1b metastases with distant spread. Conclusions: Our observations of a rising proportion of diagnoses in adolescence, reductions in primary tumor size, and decreased frequency of multifocality and distant metastases may reflect increased detection of patients with less aggressive DTC at earlier disease stages. Nonetheless, we found persistently substantial rates of locoregionally advanced disease features (multifocality, extrathyroidal invasion, and lymph node metastases), which multivariable analyses suggested have significant associations with lateral lymph node and/or distant metastases.

Polish diagnostic and therapeutic recommendations for adrenocortical carcinoma.

Advances in the diagnosis and treatment of adrenocortical carcinoma (ACC), along with the development of new therapeutic and diagnostic methods, have prompted a team of experts to formulate the first Polish guidelines for managing ACC. This article presents the diagnostic and therapeutic recommendations resulting from the discussion of specialists from various medical specialities, who participated in a series of online meetings aimed at developing consistent and effective recommendations under the National Oncology Strategy. These guidelines aim to optimise ACC treatment in Poland through coordinated efforts of multidisciplinary specialist teams, ensuring an effective and modern approach.

Polish experience in Peptide receptor radionuclide therapy.

PATIENTS AND METHODS: During the period from April 2004 to December 2010, 358 patients underwent peptide receptor radionuclide therapy (PRRT) ((90)Y-DOTATATE, (177)Lu-DOTATATE, and (90)Y/(177)Lu-DOTATATE) in Poland. RESULTS: The majority of patients underwent (90)Y-DOTATATE therapy (n = 177) with progression-free survival (PFS)/time to progression (TTP) of 17-44 months and overall survival (OS) of 22-34.2 months. Twelve-month follow-up revealed stable disease (SD) in 46-60%, disease regression (RD) in 16-35%, disease progression (PD) in 7-17%, and complete remission (CR) in 3% of patients. In patients treated with (90)Y/(177)Lu-DOTATATE (n = 44), PFS/TTP was 24.2-28.3 months and OS was 49.8-52.8 months. Twelve-month follow-up showed SD in 62-70%, RD in 15-20%, and PD in 10-12% of patients. The treatment was well tolerated. No severe adverse events occurred. Grade 3 toxicity [in leucocytes (WBC) and thrombocytes (PLT)] was seen in 6-20% of patients treated with (90)Y-DOTATATE. In that group, renal toxicity grade 3 was seen in 5-12% and grade 4 in 3-8%. In patients treated with tandem therapy with (90)Y/(177)Lu-DOTATATE or (177)Lu-DOTATATE alone, hematological and renal toxicity grade 3 or 4 was not observed. CONCLUSIONS: The results indicate that PRRT with the procedures and isotopes used is an effective and safe therapy option for patients with metastatic or inoperable neuroendocrine tumors (NETs). Our results suggest that tandem therapy with (90)Y/(177)Lu-DOTATATE provides longer overall survival than single-isotope treatment. Hematological toxicity was rare in all treated patients. Renal toxicity grade 3 and 4 was observed only in the group treated with (90)Y-DOTATATE.

Thyroid remnant ablation with radioiodine activity of 30, 60, and 100 mCi in patients with differentiated thyroid cancer - a prospective comparison of long-term outcomes.

Introduction: The aim of this prospective study was to evaluate long-term outcomes in differentiated thyroid cancer (DTC) patients postoperatively treated with distinct RAI activities of 30 mCi, 60 mCi, and 100 mCi. Material and methods: The analysis involved 277 low-risk and 46 intermediate-risk patients, who underwent radioiodine (RAI) ablation with 30 mCi, 60 mCi or 100 mCi under prospective, randomized clinical trials. Seventy-eight patients from the low-risk group received 30 mCi, whereas 125 and 74 patients received 60 mCi and 100 mCi, respectively. Regarding the intermediate-risk group, 20 patients were given 60 mCi, and 26 subjects were given 100 mCi. The mean time of follow-up was 11 years. Results: An excellent treatment response was obtained in 88%, 89% and 90% of low-risk patients treated with 30 mCi, 60 mCi, and 100 mCi, respectively, and in 85% of intermediate-risk patients, who were administered 60 or 100 mCi. An indeterminate response was achieved in 9.4% and 6.5%, whereas an incomplete structural response was obtained in 1.4% and 6.5% of low-risk and intermediate-risk patients, respectively. An incomplete biochemical response was observed only in 2.2% of intermediate-risk patients. The differences in treatment response regarding RAI activity were not significant. Conclusions: RAI activity of 30 mCi demonstrates a comparable efficacy as 60 mCi and 100 mCi in low-risk DTC. RAI activity of 60 mCi seems to be effective in intermediate-risk DTC.

2022 ETA Consensus Statement: What are the indications for post-surgical radioiodine therapy in differentiated thyroid cancer?

Modern use of post-operative radioactive iodine (RAI) treatment for differentiated thyroid cancer (DTC) should be implemented in line with patients' risk stratification. Although beneficial effects of radioiodine are undisputed in high-risk patients, controversy remains in intermediate-risk and some low-risk patients. Since the last consensus on post-surgical use of RAI in DTC patients, new retrospective data and results of prospective randomized trials have been published, which have allowed the development of a new European Thyroid Association (ETA) statement for the indications of post-surgical RAI therapy in DTC. Questions about which patients are candidates for RAI therapy, which activities of RAI can be used, and which modalities of pre-treatment patient preparation should be used are addressed in the present guidelines.

Diagnosis and treatment of thyroid cancer in adult patients - Recommendations of Polish Scientific Societies and the National Oncological Strategy. 2022 Update [Diagnostyka i leczenie raka tarczycy u chorych doroslych - Rekomendacje Polskich Towarzystw Naukowych oraz Narodowej Strategii Onkologicznej. Aktualizacja na rok 2022].

The guidelines Thyroid Cancer 2022 are prepared based on previous Polish recommendations updated in 2018. They consider international guidelines - American Thyroid Association (ATA) 2015 and National Comprehensive Cancer Network (NCCN); however, they are adapted according to the ADAPTE process. The strength of the recommendations and the quality of the scientific evidence are assessed according to the GRADE system and the ATA 2015 and NCCN recommendations. The core of the changes made in the Polish recommendations is the inclusion of international guidelines and the results of those scientific studies that have already proven themselves prospectively. These extensions allow de-escalation of the therapeutic management in low-risk thyroid carcinoma, i.e., enabling active surveillance in papillary microcarcinoma to be chosen alternatively to minimally invasive techniques after agreeing on such management with the patient. Further extensions allow the use of thyroid lobectomy with the isthmus (hemithyroidectomy) in low-risk cancer up to 2 cm in diameter, modification of the indications for postoperative radioiodine treatment toward personalized approach, and clarification of the criteria used during postoperative L-thyroxine treatment. At the same time, the criteria for the preoperative differential diagnosis of nodular goiter in terms of ultrasonography and fine-needle aspiration biopsy have been clarified, and the rules for the histopathological examination of postoperative thyroid material have been updated. New, updated rules for monitoring patients after treatment are also presented. The updated recommendations focus on ensuring the best possible quality of life after thyroid cancer treatment while maintaining the good efficacy of this treatment.

Update of the diagnostic and therapeutic guidelines for gastro-entero-pancreatic neuroendocrine neoplasms (recommended by the Polish Network of Neuroendocrine Tumours) [Aktualizacja zalecen ogólnych dotyczacych postepowania diagnostyczno-terapeutycznego w nowotworach neuroendokrynnych ukladu pokarmowego (rekomendowane przez Polska Siec Guzów Neuroendokrynnych)].

Continuous progress in the diagnostics and treatment of neuroendocrine neoplasms (NENs), the emerging results of new clinical trials, and the new guidelines issued by medical societies have prompted experts from the Polish Network of Neuroendocrine Tumours to update the 2017 recommendations regarding the management of neuroendocrine neoplasms. This article presents the general recommendations for the management of NENs, resulting from the findings of the experts participating in the Fourth Round Table Conference, entitled "Polish Guidelines for the Diagnostics and Treatment of Neuroendocrine Neoplasms of the gastrointestinal tract, Zelechów, June 2021". Drawing from the extensive experience of centres treating these cancers, we hope that we have managed to formulate the optimal method of treating patients with NENs, applying the latest reports and achievements in the field of medicine, which can be effectively implemented in our country. The respective parts of this work present the approach to the management of: NENs of the stomach and duodenum (including gastrinoma), pancreas, small intestine, and appendix, as well as large intestine.

Pancreatic neuroendocrine neoplasms - update of the diagnostic and therapeutic guidelines (recommended by the Polish Network of Neuroendocrine Tumours) [Nowotwory neuroendokrynne trzustki - uaktualnione zasady diagnostyki i leczenia (rekomendowane przez Polska Siec Guzów Neuroendokrynych)].

In this paper, we present the current guidelines for the diagnostics and management of pancreatic neuroendocrine neoplasms (PanNENs) developed by Polish experts providing care for these patients in everyday clinical practice. In oncological diagnostics, in addition to biochemical tests, molecular identification with the use of NETest liquid biopsy and circulating microRNAs is gaining importance. Both anatomical and functional examinations (including new radiopharmaceuticals) are used in imaging diagnostics. Histopathological diagnosis along with immunohistochemical examination still constitute the basis for therapeutic decisions. Whenever possible, surgical procedure is the treatment of choice. Pharmacological management including biotherapy, radioisotope therapy, targeted molecular therapy and chemotherapy are important methods of systemic therapy. Treatment of PanNENs requires a multidisciplinary team of specialists in the field of neuroendocrine neoplasms.

Gastroduodenal neuroendocrine neoplasms including gastrinoma - update of the diagnostic and therapeutic guidelines (recommended by the Polish Network of Neuroendocrine Tumours) [Nowotwory neuroendokrynne zoladka i dwunastnicy z uwzglednieniem gastrinoma - uaktualnione zasady postepowania (rekomendowane przez Polska Siec Guzów Neuroendokrynnych)].

After another meeting of experts of the Polish Network of Neuroendocrine Tumours, updated recommendations for the management of patients with gastric and duodenal neuroendocrine neoplasms, including gastrinoma, have been issued. As before, the epidemiology, pathogenesis and clinical symptoms of these neoplasms have been discussed, as well as the principles of diagnostic procedures, including biochemical and histopathological diagnostics and tumour localisation, highlighting the changes introduced in the recommendations. Updated principles of therapeutic management have also been presented, including endoscopic and surgical treatment, and the options of pharmacological and radioisotope treatment. The importance of monitoring patients with gastric and duodenal NENs, including gastrinoma, has also been emphasised.

Colorectal neuroendocrine neoplasms - update of the diagnostic and therapeutic guidelines (recommended by the Polish Network of Neuroendocrine Tumours) [Nowotwory neuroendokrynne jelita grubego - uaktualnione zasady diagnostyki i leczenia (rekomendowane przez Polska Siec Guzów Neuroendokrynych)].

Colorectal neuroendocrine neoplasm (CRNEN), especially rectal tumours, are diagnosed with increased frequency due to the widespread use of colonoscopy, including screening examinations. It is important to constantly update and promote the principles of optimal diagnostics and treatment of these neoplasms. Based on the latest literature and arrangements made at the working meeting of the Polish Network of Neuroendocrine Tumours (June 2021), this paper includes updated and supplemented data and guidelines for the management of CRNEN originally published in Endokrynologia Polska 2017; 68: 250-260.

Neuroendocrine neoplasms of the small intestine and the appendix - update of the diagnostic and therapeutic guidelines (recommended by the Polish Network of Neuroendocrine Tumours) [Nowotwory neuroendokrynne jelita cienkiego i wyrostka robaczkowego - uaktualnione zasady diagnostyki i leczenia (rekomendowane przez Polska Siec Guzów Neuroendokrynnych)].

Updated Polish recommendations for the management of patients with neuroendocrine neoplasms (NENs) of the small intestine (SINENs) and of the appendix (ANENs) are presented here. The small intestine, and especially the ileum, is one of the most common locations for these neoplasms. Most of them are well-differentiated and slow-growing tumours; uncommonly - neuroendocrine carcinomas. Their symptoms may be untypical and their diagnosis may be delayed or accidental. Najczesciej pierwsza manifestacja ANEN jest jego ostre zapalenie. Typical symptoms of carcinoid syndrome occur in approximately 20-30% of SINENs patients with distant metastases. In laboratory diagnostics the assessment of 5-hydroxyindoleacetic acid concentration is helpful in the diagnosis of carcinoid syndrome. The most commonly used imaging methods are ultrasound examination, computed tomography, magnetic resonance imaging, colonoscopy and somatostatin receptor imaging. Histopathological examination is crucial for the proper diagnosis and treatment of patients with SINENs and ANENs. The treatment of choice is a surgical procedure, either radical or palliative. Long-acting somatostatin analogues (SSAs) are essential in the medical treatment of functional and non-functional SINENs. In patients with SINENs, at the stage dissemination with progression during SSAs treatment, with high expression of somatostatin receptors, radioisotope therapy should be considered first followed by targeted therapies - everolimus. After the exhaustion of the above available therapies, chemotherapy may be considered in selected cases. Recommendations for patient monitoring are also presented.

Therapeutic Strategy in Low-Risk Papillary Thyroid Carcinoma - Long-Term Results of the First Single-Center Prospective Non-Randomized Trial Between 2011 and 2015.

Optimal therapeutic strategy in low advanced papillary thyroid carcinoma (PTC) is still a matter of debate. The management differs depending on the country. A prospective non-randomized study was performed to evaluate whether less extensive surgery could be a safe, acceptable, and sufficient therapeutic option in PTC cT1N0M0 patients. The present paper summarizes the results of over a 5-year follow-up. Material: Our prospective group (PG) treated between 2011 and 2015 consisted of 139 patients with cT1aN0M0 PTC who underwent lobectomy (LT) as initial surgical treatment (PGcT1aN0M0 group) and 102 cT1bN0M0 patients in whom total thyroidectomy (TT) with unilateral central neck dissection (CND) was performed (PGcT1bN0M0). PG was compared with the retrospective group (RG) of patients who underwent TT with bilateral CND between 2004 and 2006: 103 cT1aN0M0 patients (RGcT1aN0M0) and 91cT1bN0M0 (RGcT1bN0M0). The risks of reoperation, cancer relapse and postoperative complications were analyzed. Results: Only 12 cT1aN0M0 patients (7.6%) withdrew from the trial and underwent TT with bilateral CND. Over 90% of patients accepted less extensive surgery. In 4 cT1aN0M0 cases, TT with CND was performed due to lymph node metastases found intraoperatively. The initial clinical stage according to the TNM/AJCC 7th edition was confirmed histologically in 77% of cases in PGT1aN0M0 and in 72% in PGT1bN0M0, respectively. 24 PGcT1aN0M0 patients were reoperated on. In this group, cancer lesions in the postoperative histological specimens were found in 8 cases (32%). Five-year disease-free survival (DFS) was excellent. However, no statistically significant differences were found between PG and RG groups (99.3% in PGcT1aN0M0 and 99.0%, in RGcT1aN0M0; p = 0.41 and 98%, in PGcT1bN0M0 and 94.4% in RGcT1bN0M0; p=0.19). No significant differences were observed in the incidence of early paresis of the recurrent laryngeal nerves between PG and RG. However, as predicted, LT completely eliminated the risk of postoperative hypoparathyroidism. Summary: The results of the prospective clinical trial confirm that less extensive surgery in adequately selected low-advanced PTC patients is both safe and sufficient.

Factors Modifying Outcome After MIBG Therapy in Children With Neuroblastoma-A National Retrospective Study.

BACKGROUND: Neuroblastoma is the most common pediatric extracranial tumor with varied prognoses, but the survival of treated refractory or relapsing patients remains poor. OBJECTIVE: This analysis presents the outcomes of children with neuroblastoma undergoing MIBG therapy in Poland in 2006-2019. STUDY DESIGN: A retrospective cohort of 55 patients with refractory or relapsed neuroblastoma treated with I-131 MIBG in Poland in 2006-2019 was analyzed. The endpoints were overall survival (OS), event-free survival (EFS), cumulative incidence (CI) of second cancers and CI of hypothyroidism. Survival curves were estimated using the Kaplan-Meier method and compared between the cohorts by the log-rank test. Cox modeling was adopted to estimate hazard ratios for OS and EFS, considering factors with P < 0.2. RESULTS: Fifty-five patients with a median age of 78.4 months (range 18-193) with neuroblastoma underwent one or more (4 patients) courses of MIBG I-131 therapy. Fifteen patients were not administered chemotherapy, 3 children received standard-dose chemotherapy, and 37 patients were administered high-dose chemotherapy (HDCT) (busulfan-melphalan in 24 and treosulfan-based in 12 patients). Forty-six patients underwent stem cell transplantation, with autologous (35 patients), haploidentical (6), allogeneic (4), and syngeneic grafts (1). The median time from first MIBG therapy to SCT was 22 days. Children with relapsing tumors had inferior OS compared to those with primary resistant disease (21.2% vs 58.7%, p=0.0045). Survival was better in patients without MYCN gene amplification. MIBG therapy was never curative, except in patients further treated with HDCT with stem cell rescue irrespective of the donor type. 31 patients were referred for immune therapy after MIBG therapy, and the 5-year OS in this group was superior to the untreated children (55.2% vs 32.7%, p=0.003), but the difference in the 5-year EFS was not significant (25.6% vs 32.9%, p=ns). In 3 patients, a second malignancy was diagnosed. In 19.6% of treated children, hypothyroidism was diagnosed within 5 years after MIBG therapy. CONCLUSION: MIBG therapy can be incorporated into the therapeutic strategy of relapsed or resistant neuroblastoma patients as preconditioning with HDCT rather than stand-alone therapy. Follow-up is required due to the incidence of thyroid failure and risk of second cancers.