Radiotherapy is one of the key treatment modalities for primary prostate cancer. During the last decade, significant advances were made in radiotherapy technology leading to increasing both physical ...and biological precision. Being a loco-regional treatment approach, radiotherapy requires accurate target dose deposition while sparing surrounding healthy tissue. Conventional radiotherapy is based on computerized tomography (CT) images both for radiotherapy planning and image-guidance, however, shortcomings of CT as soft tissue imaging tool are well known. Nowadays, our ability to further escalate radiotherapy dose using hypofractionation is limited by uncertainties in CT-based image guidance and verification. Magnetic resonance imaging (MRI) is a well established imaging method for pelvic organs. In prostate cancer specifically, MRI accurately depicts prostate zonal anatomy, rectum, bladder, and pelvic floor structures with previously unseen precision owing to its sharp soft tissue contrast. The advantages of including MRI in the clinical workflow of prostate cancer radiotherapy are multifold. MRI allows for true adaptive radiotherapy to unfold based on daily MRI images taken before, during and after each radiotherapy fraction. It enables accurate dose escalation to the prostate and intraprostatic tumor lesions. Technically, MRI high-strength magnetic field and linear accelerator high energy electromagnetic beams are hardly compatible, and important efforts were made to overcome these technical challenges and integrate MRI and linear accelerator into one single treatment device, called MRI-linac. Different systems are produced by two leading vendors in the field and currently, there are around 100 MRI-linacs worldwide in clinical operations. In this narrative review paper, we discuss historical perspective of image guidance in radiotherapy, basic elements of MRI, current clinical developments in MRI-guided prostate cancer radiotherapy, and challenges associated with the use of MRI-linac in clinical practice.
The bone health guidelines for breast cancer (BC) patients recommend bone mineral density (BMD) testing. Patients with low BMD and elevated serum calcium levels (SCLs) are further evaluated for ...primary hyperparathyroidism (PHPT). We aimed to determine the prevalence of PHPT in treated BC patients with low BMD and analyze the association of SCLs with histopathologic tumor features and cancer treatment. This retrospective study included postmenopausal BC patients examined at Osteoporosis Clinic between 2013 and 2020. Clinical and BMD data were collected from patient medical records. Patients with biochemical suspicion of PHPT underwent standard parathyroid imaging procedures. Nine out of 137 (6.6%) patients were diagnosed with PHPT; 8/9 patients underwent parathyroidectomy and one patient was advised to follow-up. Among the rest of 128 non-PHPT patients, higher SCLs showed a trend of positive association with higher tumor grade and axillary lymph node involvement, and received immunotherapy, although without statistical significance. We found a higher prevalence of PHPT in treated BC patients compared to the general population. Higher SCLs show a trend of positive correlation with some more aggressive histopathologic tumor features and with immunotherapy. The results of this study suggest that assessment of SCLs should be routinely performed to rule out PHPT in treated BC patients with low BMD.
The concentration of interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) in the blood is higher in patients with active multiple sclerosis (MS) compared to those with inactive disease. The ...concentration of IL-6 and TNF-α in the blood is higher in patients with Hashimoto's thyroiditis (HT) compared to those with a healthy thyroid. The aim of the study was to assess whether serum IL-6 and TNF-α levels correlated with saliva in patients with inactive MS and whether there was a difference in these groups of patients depending of thyroid status. We also examined the correlation of thyroid stimulating hormone (TSH) levels with thyroid status. The study included 54 patients in the inactive phase of MS. The level of cytokines in the blood was determined by chemiluminescence, and in saliva by ELISA. Blood and saliva IL-6 levels showed positive correlation, while blood and saliva TNF-α levels were not correlated. There was a significantly higher TSH level in patients with inactive MS with positive thyroid antibodies, without therapy, compared with those with negative antibodies.
We present a case of a patient with simultaneous cervical lymph node metastasis of papillary thyroid cancer (PTC) and cecum neuroendocrine tumor (NET). A 45-year-old male patient with the diagnosis ...of metastatic NET of the cecum underwent fine needle aspiration (FNA) of a positron emission tomography with 18F-fluorodeoxyglucose (18F-FDG PET) positive nodule in the left thyroid lobe. Due to FNA finding suspect of PTC, the patient underwent total thyroidectomy with central neck dissection. Histopathologic finding revealed PTC of the left thyroid lobe and small solitary lymph node PTC metastasis in the central neck region. Postoperative evaluation with neck ultrasound (US) revealed two enlarged suspected lymph nodes in cervical regions III and IV on the left side of the neck and the patient underwent FNA with measurement of thyroglobulin (Tg) in the aspirates. The FNA finding of the cervical lymph node in the region III revealed PTC metastasis with high Tg value in the aspirate, while FNA finding of the cervical lymph node in the region IV revealed NET metastasis with low Tg value in the aspirate. Postoperative serum Tg value was 17.75 µg/L and the patient underwent 5550 MBq iodine-131 (I-131) therapy. A year after I-131 therapy, follow-up neck US demonstrated complete cure of PTC cervical lymph node metastasis in the region III and stable in size NET cervical lymph node metastasis in the region IV. To our knowledge, this is the first report of simultaneous occurrence of cervical lymph node metastases of PTC and NET of the cecum.
Background: We investigated the potential use of SPECT quantification in addition to qualitative brain perfusion analysis for the detection of anti-NMDAR encephalitis. The question is how to ...normalize brain activity to be able to quantitatively detect perfusion patterns. Usually, brain activity is normalized to a structure considered unaffected by the disease. Methods: Brain 99mTc-HMPAO SPECT was performed as a method to detect brain perfusion patterns. The patterns of abnormal brain perfusion cannot always be reliably and qualitatively assessed when dealing with rare diseases. Recent advances in SPECT quantification using commercial software have enabled more objective and detailed analysis of brain perfusion. The cerebellum and whole brain were used as the normalization structures and were compared with visual analysis. Results: The quantification analysis performed with whole brain normalization confirmed right parietal lobe hypoperfusion while also detecting statistically significant left-to-right perfusion differences between the temporal lobe and thalamus. Whole brain normalization further described bilateral frontal lobe hyperperfusion, predominantly of the left lobe, and was in accordance with visual analysis. Conclusion: SPECT quantitative brain perfusion analysis, using the whole brain as the normalization structure rather than the cerebellum, in this case, improved confidence in the visual detection of anti-NMDAR encephalitis and provided unexpected solutions to atypical psychiatric dilemmas.
Background: Indolent nature but a high incidence of differentiated thyroid cancer (DTC) remains a challenge for optimizing patient care. Therefore, prognostic factors present valuable information for ...determining an adequate clinical approach. Methods: This study assessed prognostic features of 1167 papillary (PTC) and 215 follicular (FTC) thyroid cancer patients that had undergone surgery between 1962 and 2012, and were followed-up up to 50 years in a single institution, till April 2020. Age, gender, tumor size, presence of local and distant metastases at presentation, extrathyroidal extension, disease recurrence, and cancer-specific survival were evaluated. Results: In multivariate analysis, factors affecting the worse outcome were age (p = 0.005), tumor size (p = 0.006), and distant metastases (p = 0.001) in PTC, while extrathyroidal extension (p < 0.001), neck recurrence (p = 0.002), and distant metastases (p < 0.001) in FTC patients. Loco-regional recurrence rate was 6% for PTC and 4.7% for FTC patients, while distant metastases were detected in 4.2% PTC and 14.4% of FTC patients. The 10-year cancer-specific survival rates for PTC and FTC were 98.6% and 89.8%, respectively (p < 0.001). Conclusions: Negative prognostic factors, besides distant metastases, were older age and greater tumor size in PTC, and extrathyroidal extension and neck recurrence in FTC patients. The recurrence and mortality rates were very low.
Parathyroid scintigraphy with
99m
Tc-MIBI is an imaging technique used in nuclear medicine and performed in patients with suspected hyperparathyroidism (HPT). The objective of this study was to ...evaluate the role of this technique in patients who, along with suspected HPT, also have thyroid nodules. Retrospective analysis included a period of 8 years (2006-2013). The study included 91 patients with clinical or laboratory suspected HPT. Pathologic changes in parathyroid glands were demonstrated in 47 (70%) of 67 patients with positive scintigraphy. Pathologic changes in parathyroid glands were not evident in the remaining 20 (30%) patients. Out of nine patients with negative scintigraphy results but with suspected enlargement of the parathyroid gland examined by ultrasound, eight (89%) patients did not show pathologic changes in the parathyroid gland, whereas one (11%) patient had evident changes. Eight (54%) of 15 patients with suspected scintigraphy had positive ultrasound findings, as well as fine needle aspiration cytology (FNAC) findings with parathyroid hormone (PTH) determination in the aspirate. Seven (46%) patients had negative FNAC findings and PTH in the aspirate. The study showed scintigraphy to have high sensitivity (98%) in detecting patients with pathologic changes in the parathyroid glands. In patients with suspected HPT, scintigraphy needs to be combined with FNAC and PTH determination in the aspirate due to its low specificity of 28%.
The studying of prostate cancer genomics is important for understanding prostate cancer biology, it can provide clinically relevant stratification into subtypes, the development of new prognostic and ...predictive markers in the context of precision medicine, and the development of new targeted therapies. Recent studies have provided detailed insight into genomics, epigenomics and proteomics of prostate cancer, both primary and metastatic castration-resistant (mCRPC). Many mutations have been discovered, both those that occur early in the carcinogenesis and progression as well as those responsible for the resistance to therapy occurring later under the influence of treatment. A large number of characteristic mutated signaling pathways has been identified, e.g. the mutations in DNA repair pathway were found in 23% of mCRPC, which suggests potential response to PARP inhibitors. Multifocality and intralesional genomic heterogeneity of prostate cancer make the clinical application of genomics complicated. Although a great progress was made in understanding prostate cancer genomic, and clinical studies related to its routine application are ongoing, prostate cancer genomics still needs to find its standard wide routine application in patients with prostate cancer.
Intensity modulated radiotherapy (IMRT) has become widely used as a standard radiation therapy technique for the treatment of localized prostate cancer. The transition from conformal radiotherapy (3D ...CRT) to a more complex IMRT technique triggered the need for more thorough verification of the accuracy in the dose delivery. In this work we present the clinical workflow and the results of patient specific quality assurance (PSQA) procedures for 40 prostate cancer patients who have been treated with step and shot IMRT ever since its implementation in our routine clinical practice. PSQA procedures include dosimetric verification of each treatment plan with dedicated rotational phantom and high-resolution matrix detector system Octavius 4D (PTW Freiburg) that allows three-dimensional comparison of the calculated and delivered radiation dose distribution. Our results proved the compliance with the universal tolerance limits recommended for those procedures (1), assuring the safety of the treatment and providing the possibility for the adoption of more stringent constraints in the future.
The activity of nicotinamide N-methyltransferase (NNMT) is tightly linked to the maintenance of the nicotinamide adenine dinucleotide (NAD+) level. This enzyme catalyzes methylation of nicotinamide ...(NAM) into methyl nicotinamide (MNAM), which is either excreted or further metabolized to N1-methyl-2-pyridone-5-carboxamide (2-PY) and H2O2. Enzymatic activity of NNMT is important for the prevention of NAM-mediated inhibition of NAD+-consuming enzymes poly–adenosine -diphosphate (ADP), ribose polymerases (PARPs), and sirtuins (SIRTs). Inappropriately high expression and activity of NNMT, commonly present in various types of cancer, has the potential to disrupt NAD+ homeostasis and cellular methylation potential. Largely overlooked, in the context of cancer, is the inhibitory effect of 2-PY on PARP-1 activity, which abrogates NNMT’s positive effect on cellular NAD+ flux by stalling liberation of NAM and reducing NAD+ synthesis in the salvage pathway. This review describes, and discusses, the mechanisms by which NNMT promotes NAD+ depletion and epigenetic reprogramming, leading to the development of metabolic plasticity, evasion of a major tumor suppressive process of cellular senescence, and acquisition of stem cell properties. All these phenomena are related to therapy resistance and worse clinical outcomes.
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