[Clinicopathological characterization and autopsybased classification of the Cancer of Unknown Primary origin (CUP) syndrome]

Cancer of Unknown Primary origin (CUP) is characterized by metastatic tumor spread without identifiable primary tumor. CUP cohort was selected from 6966 autopsy cases (2001-2014). Type-1 ("clinical") CUPs: primary site was not found clinically but identified by autopsy. Type-2 ("clinicopathological") CUPs: no primary site either clinically or by autopsy. Type-3 ("pathological") CUPs: no tumor was suspected clinically whereas autopsy revealed metastatic spread from unidentifiable source. 2160 malignant tumors were found including 80 CUPs (type-1/2/3: 42/29/9). Cumulative incidence declined with time (3.70%; 2001-2007: 4.51%; 2008-2014: 3.19%) due to decreasing incidence of type-1 and -3 CUPs. CUPs were mostly adenocarcinomas and type-1 CUPs usually originate from the lung or pancreas. As a conclusion, type-2 and -3 CUPs may originate from microscopic-sized metastasizing primary tumors. Based on the above classification, improvement of clinical diagnostics may contribute to decreased incidence of type-1 CUPs and transfer of type-3 CUPs into type-2 category.

PREDICTIVE VALUE OF SOMATIC MUTATIONS FOR THE DEVELOPMENT OF MALIGNANCY IN THYROID NODULES BY CYTOPATHOLOGY

OBJECTIVE

The purpose of our prospective longitudinal study was to evaluate the predictive efficacy of genetic testing for malignancies in fine-needle aspiration biopsy samples that are cytologically benign at the time of biopsy.

METHODS

A total of 779 aspirated cytological samples collected from thyroid nodules of 626 patients were included in a 3-year follow-up study. Consecutive patients with cytologically benign thyroid nodules by the Bethesda System for Reporting Thyroid Cytopathology were enrolled in the study. At enrollment, somatic 1-point nucleotide polymorphisms of BRAF and RAS family genes were tested by melting-point analysis, while RET/PTC and PAX8/PPAR-gamma rearrangements were examined by real-time polymerase chain reaction. The genetic test was considered to be positive if a somatic mutation was found. Malignant cytopathologic diagnoses were confirmed by histopathology.

RESULTS

In samples collected from 779 thyroid nodules, there were 39 BRAF, 33 RAS mutations, and 1 RET/PTC rearrangements found at the beginning of the study. No PAX8/PPAR-gamma rearrangement was identified. There were 52 malignant thyroid tumors removed during follow-up, out of which 24 contained a somatic mutation. The specificity of the presence of somatic mutations for malignancies was as high as 93.3%, and sensitivity was 46.2%. The negative predictive value of genetic testing reached 96.0%.

CONCLUSION

Our results show that our set of genetic tests can predict the appearance of malignancy in benign thyroid nodules (at the beginning of follow-up) with high specificity and strong negative predictive value.

ABBREVIATIONS

BRAF = v-raf murine sarcoma viral oncogene homolog B1 FLUS = follicular lesion of undetermined significance FNAB = fine-needle aspiration biopsy FTC = follicular thyroid carcinoma HRAS = homologous to the oncogene from the Harvey rat sarcoma virus KRAS = homologous to the oncogene from the Kirsten rat sarcoma virus NRAS = first isolated from a human neuroblastoma/neuroblastoma RAS = viral oncogene homolog PAX8 = paired box 8 PCR = polymerase chain reaction PPAR-gamma = peroxisome proliferator-activated receptor gamma PTC = papillary thyroid carcinoma RAS = rat sarcoma RET = rearranged during transfection tyrosine-kinase proto-oncogene SM = somatic mutation SNP = single-nucleotide polymorphism.

[The role of aspiration cytology in tumor diagnostics]

Fine needle aspiration biopsy (FNAB) of focal lesions is a quick, relatively simple and cost-effective diagnostic method. However, performing aspirations and interpreting smears require skill and experience. Before initiating an aspiration the doctor needs to be aware of the limits of cytology as it is vital to know what kind of diagnostic issues can be answered upon a smear and what kind of questions cannot. Traditionally FNAB was performed without radiologic guidance, and therefore almost only palpable lesions were aspirated. Since ultrasound (US) has become widely used in medicine, it is axiomatical that FNAB is ideally performed with US guidance not only for the protection of the patients but also for targeting the lesion more safely. Several cytologists find US guidance unnecessary as a routinely used examination, which may lead to unsatisfactory smears and false negative results. This means not only a loss for the patient, but leads to a negative judgement of this diagnostic method. Our interventional cytology diagnostic team developed a working method resulting in excellent statistical results. In the followings we would like to share our experience refined the past two decades to restore the reputation of this diagnostic method.

Total aortic arch replacement: superior ventriculo-arterial coupling with decellularized allografts compared with conventional prostheses

Background

To date, no experimental or clinical study provides detailed analysis of vascular impedance changes after total aortic arch replacement. This study investigated ventriculoarterial coupling and vascular impedance after replacement of the aortic arch with conventional prostheses vs. decellularized allografts.

Methods

After preparing decellularized aortic arch allografts, their mechanical, histological and biochemical properties were evaluated and compared to native aortic arches and conventional prostheses in vitro. In open-chest dogs, total aortic arch replacement was performed with conventional prostheses and compared to decellularized allografts (n = 5/group). Aortic flow and pressure were recorded continuously, left ventricular pressure-volume relations were measured by using a pressure-conductance catheter. From the hemodynamic variables end-systolic elastance (Ees), arterial elastance (Ea) and ventriculoarterial coupling were calculated. Characteristic impedance (Z) was assessed by Fourier analysis.

Results

While Ees did not differ between the groups and over time (4.1±1.19 vs. 4.58±1.39 mmHg/mL and 3.21±0.97 vs. 3.96±1.16 mmHg/mL), Ea showed a higher increase in the prosthesis group (4.01±0.67 vs. 6.18±0.20 mmHg/mL, P<0.05) in comparison to decellularized allografts (5.03±0.35 vs. 5.99±1.09 mmHg/mL). This led to impaired ventriculoarterial coupling in the prosthesis group, while it remained unchanged in the allograft group (62.5±50.9 vs. 3.9±23.4%). Z showed a strong increasing tendency in the prosthesis group and it was markedly higher after replacement when compared to decellularized allografts (44.6±8.3dyn·sec·cm⁻⁵ vs. 32.4±2.0dyn·sec·cm⁻⁵, P<0.05).

Conclusions

Total aortic arch replacement leads to contractility-afterload mismatch by means of increased impedance and invert ventriculoarterial coupling ratio after implantation of conventional prostheses. Implantation of decellularized allografts preserves vascular impedance thereby improving ventriculoarterial mechanoenergetics after aortic arch replacement.

In vitro generation of atrioventricular heart valve neoscaffolds

Tissue engineering of cardiovascular structures represents a novel approach to improve clinical strategies in heart valve disease treatment. The aim of this study was to engineer decellularized atrioventricular heart valve neoscaffolds with an intact ultrastructure and to reseed them with umbilical cord-derived endothelial cells under physiological conditions in a bioreactor environment. Mitral (n=38) and tricuspid (n=36) valves were harvested from 40 hearts of German Landrace swine from a selected abattoir. Decellularization of atrioventricular heart valves was achieved by a detergent-based cell extraction protocol. Evaluation of the decellularization method was conducted with light microscopy and quantitative analysis of collagen and elastin content. The presence of residual DNA within the decellularized atrioventricular heart valves was determined with spectrophotometric quantification. The described decellularization regime produced full removal of native cells while maintaining the mechanical stability and the quantitative composition of the atrioventricular heart valve neoscaffolds. The surface of the xenogeneic matrix could be successfully reseeded with in vitro-expanded human umbilical cord-derived endothelial cells under physiological flow conditions. After complete decellularization with the detergent-based protocol described here, physiological reseeding of the xenogeneic neoscaffolds resulted in the formation of a confluent layer of human umbilical cord-derived endothelial cells. These results warrant further research toward the generation of atrioventricular heart valve neoscaffolds on the basis of decellularized xenogeneic tissue.

Reendothelialization of human heart valve neoscaffolds using umbilical cord-derived endothelial cells

BACKGROUND

Heart valve tissue engineering represents a concept for improving the current methods of valvular heart disease therapy. The aim of this study was to develop tissue engineered heart valves combining human umbilical vein endothelial cells (HUVECs) and decellularized human heart valve matrices.

METHODS AND RESULTS

Pulmonary (n=9) and aortic (n=6) human allografts were harvested from explanted hearts from heart transplant recipients and were decellularized using a detergent-based cell extraction method. Analysis of decellularization success was performed with light microscopy, transmission electron microscopy and quantitative analysis of collagen and elastin content. The decellularization method resulted in full removal of native cells while the mechanical stability and the quantitative composition of the neoscaffolds was maintained. The luminal surface of the human matrix could be successfully recellularized with in vitro expanded HUVECs under dynamic flow conditions. The surface appeared as a confluent cell monolayer of positively labeled cells for von Willebrand factor and CD 31, indicating their endothelial nature.

CONCLUSIONS

Human heart valves can be decellularized by the described method. Recellularization of the human matrix resulted in the formation of a confluent HUVEC monolayer. The in vitro construction of tissue-engineered heart valves based on decellularized human matrices followed by endothelialization using HUVECs is a feasible and safe method, leading to the development of future clinical strategies in the treatment of heart valve disease.

[Comparative study of somatic oncogene mutations in normal thyroid tissues and thyroid neoplasms]

It is established that numerous somatic oncogene mutation (BRAF, NRAS, HRAS, KRAS) and gene translocations (RET/PTC, PAX8/PPAR-gamma) are associated with the development of thyroid cancer. In this study 22 intraoperative thyroid tissue samples (11 pathologic and 11 normal) were examined. Somatic single nucleotide polymorphisms were analyzed by LigthCycler melting method, while translocations were identified by real-time polymerase chain reaction technique. In tumorous sample 3 BRAF, 2 NRAS and one HRAS mutations were found, as well as one RET/PTC1 translocation. Results confirm international data showing that these oncogene mutations and translocations are linked to thyroid cancer. Cytological examination completed with genetic data may support the diagnosis of thyroid malignancies. In addition, genetic alterations may indicate malignant transformation and may become prognostic factors in future.

[Immunohistochemical phenotype of breast carcinomas predicts the effectiveness of primary systemic therapy]

The purpose of the study was to identify breast cancer subtypes by immunohistochemistry likely to respond to neoadjuvant chemotherapy and to analyze the used chemotherapy regimen and the range of response rates. Analysis of a collected database was performed. Ninety-two patients were identified in our files who received neoadjuvant chemotherapy between 1998 and 2009. We used immunohistochemical profiles (ER, PgR, HER2, Ki-67 and p53) of NCB, FNAB and surgical breast specimens to subclassify the tumors. Pathological response rates were assessed following surgical removal of tumors by using the Chevallier classification. DFS and OS was measured in 88 cases from the date of definitive surgery to the date of last follow-up or death. Pathological complete or near-complete remission (pCR = Chevallier I and II) was observed in 13 of 92 cases (14.1%). According to the preoperative characteristics of the 13 tumors achieving pCR, 9 of the cases were triple negative, one of 13 was ER-/HER2+ and three of 13 ER+/HER2+. Twenty-four of 92 patients received taxane based neoadjuvant chemotherapy, 30 of 92 anthracycline based neoadjuvant chemotherapy, 33 of 92 taxane + anthracycline regimen and 2 of 92 CMF regimen. In the taxane treated group of patients the pCR rate was 29.1%, in the anthracycline group 6.6% and in the taxane + anthracycline treated group 12.1%. Concerning DFS, significant difference was observed between the Chevallier III and IV groups (p=0.006), and less events were observed in the pCR group (not significant). pCR was associated with significantly better OS (p=0.050). It seems that even limited, routinely used immunohistochemical profiling of tumors is able to predict the likelihood of pCR to neoadjuvant chemotherapy. Patients with triple negative and HER2-positive cancers are likely to achieve pCR after neoadjuvant chemotherapy.

[Gastrointestinal stromal tumor metastasized to the ovary]

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract, is originated from the interstitial cells of Cajal. As a sign of malignancy, intestinal tumors particularly tend to metastasize, primarily in the abdominal cavity and in the liver. The authors present a gastrointestinal stromal tumor of the intestine, which metastasized to the ovary. The tumor presented as a pelvic mass, mimicking an ovarian neoplasm. In the case of clinically simultaneous tumors of the gastrointestinal tract and of the ovary, one has to consider the possibility of a primary gastrointestinal tumor and first of all a gastrointestinal stromal tumor. The histological diagnosis is essential because of the tumor-specific chemotherapeutical opportunity of gastrointestinal stromal tumors.

[Unilateral Sertoli-cell androblastoma in the ovary of a young woman]

The authors present a case of a Sertoli-cell type androblastoma of the ovary. The tumor is mainly seen in young women and is mostly discovered through hormonal dysfunctions linked to it. Histopathological evaluation is indispensable for an exact diagnosis. Because of its rarity, there is little experience with the tumor and the histological identification is also sometimes very challenging. The tumor is occasionally associated with Peutz-Jeghers syndrome, tumor of the thyroid, or goiter. Biologically it follows a low-malignant course with a fair prognosis, long-term complex patient follow up is necessary after unilateral oophorectomy of the diseased organ.

Possible role of sweating in the pathophysiology of panic attacks

In recent years the role of hyperventilation in the generation of panic attacks has attracted a considerable amount of interest. According to these studies hyperventilation can elicit the somatic symptoms of panic due to systemic alkalosis. We suggest that since in the case of panic, sweating might cause alkalosis, it could also contribute to the generation of panic attacks. In light of this hypothesis we made a statistical analysis of the panic symptoms of 111 panic patients diagnosed according to DSM-III criteria. The analysis revealed that: (1) there was a well identified group of panic patients who had minor breathing difficulties with heavy sweating; and (2) that all the patients sampled had either severe breathing, or sweating symptoms, or both. We conclude that in the absence of the intensive physical activity of the 'flight or fight' reaction, sweating as well as hyperventilation can cause alkalosis, which in turn might generate panic attacks.