Short histological kaleidoscope - recent findings in histology. Part III.

The paper provides an overview of the current understanding of different cells' biology (e.g., keratinocytes, Paneth cells, myoepithelial cells, myofibroblasts, chondroclasts, monocytes, atrial cardiomyocytes), including their origin, structure, function, and role in disease pathogenesis, and of the latest findings in the medical literature concerning the brown adipose tissue and the juxtaoral organ of Chievitz.

Short histological kaleidoscope - recent findings in histology. Part II.

This article focuses on the latest histological knowledge in the field regarding the peripheral lymphoid system [mucosa-associated lymphoid tissue (MALT), bronchus-associated lymphoid tissue (BALT), gut-associated lymphoid tissue (GALT)], the thymus stroma, some of the various corpuscles of the human body (Hassall's corpuscles in thymus, arenaceous corpuscles in pineal gland, corpora amylacea in prostate and other locations) and Fañanas glial cells in the cerebellum.

Short histological kaleidoscope - recent findings in histology. Part I.

This article is a review of new advances in histology, concerning either classification or structure of different tissular elements (basement membrane, hemidesmosomes, urothelium, glandular epithelia, adipose tissue, astrocytes), and various organs' constituents (blood-brain barrier, human dental cementum, tubarial salivary glands, hepatic stellate cells, pineal gland, fibroblasts of renal interstitium, Leydig testicular cells, ovarian hilar cells), as well as novel biotechnological techniques (tissue engineering in angiogenesis), recently introduced.

Nanocarriers for Drug Delivery: An Overview with Emphasis on Vitamin D and K Transportation.

Mounting evidence shows that supplementation with vitamin D and K or their analogs induces beneficial effects in various diseases, e.g., osteoarticular, cardiovascular, or carcinogenesis. The use of drugs delivery systems via organic and inorganic nanocarriers increases the bioavailability of vitamins and analogs, enhancing their cellular delivery and effects. The nanotechnology-based dietary supplements and drugs produced by the food and pharmaceutical industries overcome the issues associated with vitamin administration, such as stability, absorption or low bioavailability. Consequently, there is a continuous interest in optimizing the carriers' systems in order to make them more efficient and specific for the targeted tissue. In this pioneer review, we try to circumscribe the most relevant aspects related to nanocarriers for drug delivery, compare different types of nanoparticles for vitamin D and K transportation, and critically address their benefits and disadvantages.

The pioneer use of a modified PRGF-Endoret® technique for wound healing in a hemodialyzed diabetic patient in a terminal stage of renal disease.

In the literature, this paper is the first to describe the use of plasma rich in growth factors (PRGF)-Endoret® in hemodialyzed diabetic patients, to promote the healing of after amputation wounds. The PRGF-Endoret® was primarily conceived to be used in maxillofacial surgery, oral implantology, etc., the innovation residing in the blood collection technique (quantity, moment of the week, rhythmicity), which was adapted to the specific conditions of the hemodialyzed patient. Moreover, in the initial phases, the two PRGF fractions were innovatively applied as single alternating layers on the wound surface. Only after the surface of the wound decreased, the two PRGF fractions were applied as overlapping layers. Nevertheless, the paper presents the optimal method to assess the clinical evolution of the wound. Histopathological examination of the biopsy performed during wound preparation for PRGF application brought additional, essential data for orienting the therapeutic approach. The exclusion of calciphylaxis, a disease with high mortality risk, encouraged the application of this method, and also demonstrated the microscopic features in hemodialyzed diabetic patients.

Different patterns of p16INK4a immunohistochemical expression and their biological implications in laryngeal squamous cell carcinoma.

INTRODUCTION: p16INK4a immunohistochemistry (IHC) is widely used to facilitate the diagnosis of human papillomavirus (HPV)-associated neoplasia, when ≥70% of cells show strong nuclear and cytoplasmic positivity. In this study, we aim to compare partial expression patterns that do not fulfill the above criteria and seek biological implications in laryngeal squamous cell carcinoma (LSCC). MATERIALS AND METHODS: p16INK4a IHC staining was conducted on representative sections of archived tissue from 88 LSCCs. Immunoreactivity was described based on four parameters: intracellular localization of immunostaining, intensity of immunostaining, distribution pattern and percentage of positive cells. RESULTS: Six patterns of p16INK4a immunoexpression were observed and defined as: strong diffuse (strong immunostaining, expression in cytoplasm and nucleus in >70% of tumor cells), weak diffuse (moderate or weak immunostaining, expression in cytoplasm in >70% of tumor cells), marginal (strong cytoplasmic immunostaining, limited to the periphery of tumor islets), strong scattered (strong immunostaining, expression in cytoplasm and nucleus in <50% of tumor cells), weak scattered (moderate or weak immunostaining, expression in cytoplasm in <50% of tumor cells), negative (no expression). The pN stage of the patients was associated with p16INK4a immunoexpression patterns, the marginal pattern was only found in the pN0-Nx stages, while the weak diffuse pattern was more frequently observed in pN2-N3 stages. CONCLUSIONS: Partial immunostaining with architecturally distinct p16INK4a immunoexpression patterns may prove significant in stratifying characteristic clinicopathological subgroups among LSCC. Our observations may support the hypothesis that p16INK4a has different roles in different subcellular locations, with tumorigenic molecular pathways unrelated to HPV infection.

State of the art in human adipose stem cells and their role in therapy.

Nowadays, adipose tissue appears to be the most valuable source in regenerative cell therapy, due to the following characteristics: high accessibility, high expression in a large number of individuals, high self-renewal and ability to differentiate, and hematopoietic support to the implant area. Its therapeutic potential has been experimentally observed in a broad spectrum of diseases with high population impact: diabetes, myocardial infarction, Parkinson disease, bone fractures, facial reconstruction or loss of subcutaneous tissue due to congenital abnormalities (e.g., hemifacial microsomy), trauma, burns, and tumors. Over 130 clinical trials using adipose-derived stem cells (ASCs), majority phase I or phase II, have been registered with the National Institutes of Health (NIH), and in the short term no adverse reactions or significant risks were identified. Parallel with regulatory frameworks that control their safety and assess their efficacy, phase III trials are being developed. Although transplantation with adipose tissue is becoming more and more popular, there are still important drawbacks and technical challenges to be addressed, and clinical strategies to be developed. This review explores in a concise manner the present body of knowledge concerning ASCs and their implication in therapy.

Diagnostic and therapeutic approaches in oral cavity granulomas based on new data concerning their origin and pathogenesis.

Giant cell granulomas in the oral cavity are reactive hyperplastic lesions that arise either peripherally in the mucoperiosteum or centrally in the bone. The peripheral giant cell granuloma (PGCG) is a benign lesion induced by local chronic irritation. It may develop at any age, and tends to be more frequent in females. Central giant cell granuloma (CGCG) is a reactive lesion of unknown etiology. It commonly occurs in children and young adults. It is also predominant in females and frequently located in the anterior part of the mandible. Histologically, PGCG and CGCG have similar features. The lesions are non-encapsulated proliferations of oval and spindle-shaped mononuclear cells (MCs) and multiple multinucleated giant cells (MGCs) in a vascular supporting stromal tissue, associated with foci of hemorrhage. Despite the similar microscopic features, PGCG and CGCG have different clinical behavior. PGCG is usually reduced in size and asymptomatic. It grows locally, as an exophytic lesion on the alveolar mucosa, but may become slightly infiltrative in the underlying periosteum and bone. After complete excision and curettage, it has a low recurrence rate. Contrarily, CGCG has an aggressive behavior, with rapid growth and intense osteolytic activity causing perforation of the cortical plate, teeth malposition and pain. Moreover, it is characterized by a high recurrence rate. This review focuses on the origin and activating pathways of MCs and MGCs, discusses the mechanisms underlying their biological activity, tries to explain the variable clinical behavior and proposes therapeutic approaches for the granulomas associated with the jaw bones.

Could oral cytomorphometry be of value in distinguishing diabetes mellitus?

The present study refers to a quantitative, morphometric analysis of exfoliative cytology smears collected from diabetes mellitus (DM) patients, in order to distinguish subtle changes in cellular and nuclear parameters. The study was carried out on 30 adult subjects: a control group of 10 healthy subjects and a study group of 20 diabetic subjects (type 1 and type 2 DM). Another factor that was taken into consideration was the abundance of the microbial flora. The oral smears were stained using Hematoxylin and Eosin and several parameters were measured (nuclear diameter, perimeter and area, cell large diameter and area), and calculated: nuclear/cytoplasmic ratio and nuclear roundness factor. We found out that the cells collected from DM patients had higher values of the nuclear parameters (the nuclei were larger) and lower cell dimensions. The nuclear to cytoplasmic ratio was increased in these patients, but the nuclear roundness factor was closer to one in the study group. Also, an increased number of bacteria, often seen in DM patients, decreased the nuclear parameters. Our findings complete recently descriptive cytology studies with the morphological measurements in case of bacterial abundance and sustain the possible value as screening method for morphometry.

Hemorrhagic polypoid gastric and colonic metastases nine years after uterine leiomyosarcoma - case report.

INTRODUCTION: Uterine leiomyosarcoma (ULMS) is a rare tumor, representing 1-2% of all uterine malignancies. It is highly aggressive, with high metastatic rate, especially in lungs, peritoneal cavity, retroperitoneum, bones and liver, usually during the first years after diagnosis. CASE PRESENTATION: A 58-year-old woman, with subtotal hysterectomy and bilateral adnexectomy, followed by radiochemotherapy for spindle-type ULMS nine years ago, presented with gastrointestinal bleeding and severe anemia. Three polyps ranging from 2 cm to 5 cm in diameter were found at gastroscopy, the largest being ulcerated, which required a total gastrectomy three months later. Colonoscopy identified two pedunculated polyps on the descending colon, 2 cm and 3.5 cm in diameter. Histologically, both sites revealed proliferations of spindle cells with whorled pattern, moderate to severe nuclear atypia, 5 to 8 mitotic figures (MFs)÷10 high-power fields (HPFs) and additional necrosis in the gastric tumors. Immunohistochemistry was negative for CD117, DOG1, S100 and CD34 and positive for smooth muscle actin (SMA), estrogen receptor (ER) and progesterone receptor (PR). Twenty percent of nuclei stained positive for Ki67. The diagnosis was synchronous hemorrhagic gastric and colonic polypoid metastases of ULMS. Thoracic computed tomography (CT) and abdominal ultrasonography were negative for other metastatic lesions, while abdominal CT revealed abdominal and pelvic lymphadenopathy. CONCLUSIONS: This case illustrates a distinct pattern of metastasis that is an extremely rare gastric and colonic location and an expanded disease-free period of nine years since the initial treatment. A long-term clinical and imaging follow-up of this patient is essential.

Solitary Langerhans histiocytosis of the orbit: case report and review of the literature.

Langerhans cell histiocytosis (LCH), previously known as "histiocytosis X", is a clinical entity characterized by abnormal proliferation of Langerhans cells, which exert a mass effect. Orbital involvement due to LCH is rare as a unifocal disease, seldom occurring outside the pediatric population. We report a case of a 21-year-old man with solitary LCH of the orbit depicted by magnetic resonance imaging (MRI) and diagnosed by histopathological examination.

Keratoacanthoma of the conjunctiva - case report and review of the literature.

INTRODUCTION: Keratoacanthoma (KA) is a relatively common, benign, rapidly growing and self-limiting squamous proliferation, which appears most frequently on the sun-exposed skin. The nature of KA and its relationship to squamous cell carcinoma (SCC) still represent one of the major debates in dermatopathology, as it is the truthfulness of such a diagnosis outside the skin. However, the tumor is now known to originate from the pilosebaceous units of the skin or from ectopic sebaceous glands of squamous mucous membranes, and to differentiate onto follicular isthmus÷infundibulum-like epithelium. CASE PRESENTATION: A 71-year-old man presented with a sore and red right eye, which on slit-lamp biomicroscopical examination revealed a dome-shaped lesion at the temporal inferior conjunctival limbus. After a thorough histopathological examination, a diagnosis of KA has been made, both after the initial tumor excision and after the relatively rapid recurrence. After the second intervention, no recurrence was observed over five years of follow-up, confirming the diagnosis. CONCLUSIONS: The peculiarity of the case stands in his exceptional rarity, being to our knowledge the first conjunctival KA reported in our country. In the light of current knowledge, the peculiar limbal location of all the conjunctival KAs reported in the literature raised the question of the possible role of limbal stem cells in the histogenesis of these tumors, similar to the pilosebaceous ones. The treatment of conjunctival KA remains the complete excision of the tumor, as it allows histopathological evaluation of the entire tumor and the exclusion of a KA-like SCCs or KAs with SCC component.

Diagnostic reevaluation of 17 cases of pheochromocytoma - a retrospective study.

A rare neuroendocrine tumor, the pheochromocytoma (PCC) raises problems due both the limited experience of the researchers in this field and its pathogenic mechanisms, still not fully elucidated. The malignant potential of this tumor cannot be predicted based on its macro- or microscopic aspects, but on the presence of metastases. The aims of this study were: (1) the reevaluation of data for a pertinent and complete tumor diagnostic and prognostic pattern; (2) the statistical correlation of all investigated parameters with the malignant form and the survival rate in order to obtain a possible predictor of malignancy; (3) the potential identification of initially diagnosed benign tumors that become malignant in time. The retrospective study was conducted on 17 patients diagnosed with pheochromocytoma. We investigated: the personal data, the associated neuroendocrine syndromes, the clinical, the laboratory, the macro- and microscopic data [location, size, Hematoxylin-Eosin (HE) pheochromocytoma of the adrenal gland scaled score (PASS score), and immunohistochemical aspects] and the survival rate (analyzed by Kaplan-Meier method and Log-Rank test). The influence of diagnostic parameters on malignancy was calculated taking into consideration the survival rate. By reevaluation of the 17 cases, we tried to emphasize the value of a complex diagnosis pattern for PCCs, based on the correlation between clinical data, laboratory findings and microscopic features. A significant statistical difference between benign and malignant forms was not registered, but there were parameters as age, association with neuroendocrine syndromes, PASS score and specifically Ki-67 mitotic index that had a powerful impact on the survival rate and could be consider as possible predictors of malignancy. The potential of PCC malignant transformation was revealed in our study, by two cases that have metastasized in time.

The value of exfoliative cytology in the diagnostic of oral mucosa changes in diabetes mellitus.

In this study, we performed microscopic qualitative analyses of the oral epithelium cytological smears in potential early phase of diabetes and in type 1 and 2 diabetic patients versus a healthy control group. The cytological assessment of the oral changes was realized on superficial and profound smears, from jugal and ventral tongue mucosa and it was based on the comparison between three staining methods [Papanicolaou, APT (polychrome tannin blue)-Dragan and Hematoxylin-Eosin (HE)]. Cytological changes of oral cells population were correlated with the type, duration and complications of diabetes. Oral flora was also evaluated. Irrespective the staining used, we found a clear dividing line between the control group and the real diabetic patients. In all diabetes cases (independently of the type of smear, harvest site, clinical form of disorder and present complications), cells presented alterations both at the level of cytoplasm and nucleus. Dyschromasia, cytolysis, different degrees of fatty degenerescence, binucleated cells, hyperchromasia, nuclear enlargement with modified nuclear÷cytoplasmic ratio, were the most frequent findings. There were no discrepancies in the cellular aspects of type 1 or 2 diabetic patients' smears or between the control group and the potential prediabetic status patients. Findings were interpreted as oral epithelium reactive changes induced by the disease. We concluded that exfoliative cytology alone is of low value as a diagnostic and prognostic tool in the diagnosis of diabetes mellitus (DM); it detects the reactive changes induced by the disease, but it makes no differences between DM types or degree of severity and does not allow by qualitative analysis alone to detect abnormalities in early diabetes.

Intracranial immature teratoma with a primitive neuroectodermal malignant transformation - case report and review of the literature.

INTRODUCTION: Central nervous system (CNS) germ cell tumors are very rare, accounting for 0.3-3% of primary intracranial neoplasms; of these, the teratomas are even more uncommon. The immature variant of teratomas, defined by the presence of incompletely differentiated components resembling fetal tissues is considered as having a low, almost borderline malignancy state. CASE PRESENTATION: A 35-year-old male presented with a left fronto-basal tumor. At surgery, a grey white tumor, mostly solid, was excised. The histopathological examination revealed an infiltrating teratoma. The histological spectrum varied from epithelial and mesenchymal mature to immature tissues. These structures were intimately mixed with significant areas of primitive neuroepithelial tubules and÷or primitive neuroectodermal tissues. The diagnosis was that of an immature intracranial teratoma, with high histological grade WHO (World Health Organization) (Norris grade III). After surgical resection, a rapid infratentorial contralateral subarachnoid extension followed. The second tumor was largely formed by primitive neuroectodermal tumor (PNET)-like structures and rare mature epithelial tissues, meaning a PNET-like overgrowth or "malignant transformation" of an immature teratoma. After specific oncological treatment, the patient had a favorable evolution with no signs of relapse (2016). CONCLUSIONS: The present case highlights the value of the Norris grading system (mostly used in grading ovarian immature teratomas) in a very rare case of intracerebral immature teratoma with rapid subarachnoid extension caused by an unexpected secondary "malignant transformation".

Pediatric glioblastoma with giant cells and "supratentorial" primitive neuroectodermal component - case report and review of the literature.

INTRODUCTION: The glial differentiation in pediatric "supratentorial primitive neuroectodermal tumors" (sPNET) is occasionally revealed by immunohistochemistry with GFAP (glial fibrillary acidic protein) as isolated positive cells among undifferentiated cells, indicative of divergent cellular phenotypes. Large malignant glial tumors in sPNETs are extremely rare and challenge the neuropathologist by raising the possibility of glioblastomas with sPNET-like features (GB sPNET). The distinction between them is important because of their different treatment and prognostic. CASE PRESENTATION: A large parieto-occipital tumor with minimal ventricular invasion, in an 11-year-old girl, with a five-month clinical history, was proven to be a highly malignant biphasic tumor, consisting in a glioblastoma with giant cells, representing 75% of the tumor, and sPNET nodules, with one larger dominant nodule. The immunohistochemistry confirmed positivity for synaptophysin, neurofilament, neuron-specific enolase and CD56 in the sPNET compartment and for GFAP, CD56 and vimentin in the glioblastoma. In some parts of the tumor, the two components were well delineated from each other as in a "collision" tumor, but in others, the two different tumors were intermingled. It was histologically diagnosed as sPNET with double differentiation (glial and neural) or glioblastoma with sPNET-like features. CONCLUSIONS: These cases are very rare, few reported, especially in the pediatric population, and with high difficulties in histological differential diagnosis, subsequently reflected in the therapeutic decisions.

The prognostic role of EBER in pediatric cancer.

The Epstein-Barr virus (EBV) infection is an endemic disease, over 90% of the population being exposed to it by adulthood. EBV is implicated in the etiology of a significant number of neoplasms, which acquire particular features in terms of course and prognosis. Incidence rates are much higher in children. To establish the link between EBV and neoplasms, EBER (Epstein-Barr virus non-encoded RNAs) needs to be highlighted in tumor tissue. The role of EBV in patient response to oncological treatment remains controversial.

Microglia--performers of the 21st century.

At the frontier between immunology and neuroscience, microglia, the enigmatic macrophages of the brain, have generated, in recent years, increasing interest. In response to even minor pathological changes in the brain, these extremely versatile glial cells occasionally enter in an over-activating state and produce pro-inflammatory cytokines and free radicals, thereby contributing directly to neuroinflammation and various brain disorders. This review provides an analysis of the latest developments in the microglia field, considering the important new research that illustrate their involvement in brain related diseases.

The diagnostic value of immunohistochemistry and silver impregnation techniques for characterization of normal, reactive and tumoral astrocytes.

Astrocytes represent a heterogeneous population of specialized glial cells responsible not only for accomplishing various important functions in the healthy nervous tissue, but also for reacting to all types of the central nervous system diseases and trauma. GFAP immunostaining is considered to be the most accurate of the routine techniques used for identifying astrocytes; however, silver impregnation techniques, which are inexpensive and approachable, might be a reliable alternative. The present research has brought into question and tried to assess the sensitivity and specificity of these classical methods for identifying and differentiating normal and reactive from tumoral astrocytes. Our study included 10 supratentorial gliomas specimens of various grade and two normal brain samples. We performed a histological study on consecutive seriated sections labeled using four methods: the immunostaining for GFAP (glial fibrillary acidic protein) and the three silver impregnation techniques: Ramón y Cajal, Bielschowsky-Cajal and Gömöri. For each tumoral case, two areas were examined: the tumoral parenchyma and the tumor borders (considered as reactive gliosis) and were both compared to healthy brain parenchyma; for each area, three microscopic fields were assessed and two parameters were recorded: a semi-quantitative score (the astrocytes' density) and a qualitative score (the color intensity). We used a complex statistical analysis in order to process the data and to compare the diagnostic value of silver impregnation techniques versus GFAP immunostaining (the reference method) in terms of tumoral grading and differentiating tumoral from normal and reactive astrocytes. Our results indicated that there data provided by both GFAP immunostaining and silver impregnation techniques were comparable.

Diagnostic correlation between RET proto-oncogene mutation, imaging techniques, biochemical markers and morphological examination in MEN2A syndrome: case report and literature review.

Multiple endocrine neoplasia type 2 (MEN2) is a rare autosomal dominant monogenic disorder caused mostly by missense mutations in the RET (REarranged during Transfection) proto-oncogene on chromosome 10q11.2. MEN2A represents more than 50% of all MEN2 cases, having a regular pattern with medullary thyroid carcinoma (MTC) incidence of 90-100%, bilateral pheochromocytoma (PCC) incidence of 40-50% and primary hyperparathyroidism (HPT) incidence of 10-25%. Until recently, the diagnosis of MTC was most frequently based on fine-needle aspiration of thyroid nodules, after an ultrasound examination and endocrine evaluation of serum calcitonin levels. Nowadays, RET gene screening (starting with exons 10 and 11) is a mandatory test used for identification of both symptomatic and non-symptomatic MTC carriers or for exclusion of healthy individuals from subsequent periodical clinical/biochemical screening. In this context, and in the idea of PCC preceding MTC, the early detection of germline RET mutations are highly suggestive for hereditary disease. PCC diagnosis is established in classical manner by abdominal ultrasound imaging or computed tomography confirming the presence of adrenal gland masses, elevated plasma metanephrines and normetanephrines values and histopathological examination. Additional HPT diagnosis is acknowledged by serum ionized calcium and parathormone levels. Here we report a hereditary case of MEN2A in a two-generation Romanian family, along with data presenting the importance of correlative plurifactorial diagnostic scheme in this syndrome and a short literature review.