Fibrous Histiocytoma Research Articles

Transforming Skin Cancer Diagnosis: A Deep Learning Approach with the Ham10000 Dataset

Skin cancer (SC) is one of the three most common cancers worldwide. Melanoma has the deadliest potential to spread to other parts of the body among all SCs. For SC treatments to be effective, early detection is essential. The high degree of similarity between tumor and non-tumors makes SC diagnosis difficult even for experienced doctors. To address this issue, authors have developed a novel Deep Learning (DL) system capable of automatically classifying skin lesions into seven groups: actinic keratosis (AKIEC), melanoma (MEL), benign keratosis (BKL), melanocytic Nevi (NV), basal cell carcinoma (BCC), dermatofibroma (DF), and vascular (VASC) skin lesions. Authors introduced the Multi-Grained Enhanced Deep Cascaded Forest (Mg-EDCF) as a novel DL model. In this model, first, researchers utilized subsampled multigrained scanning (Mg-sc) to acquire micro features. Second, authors employed two types of Random Forest (RF) to create input features. Finally, the Enhanced Deep Cascaded Forest (EDCF) was utilized for classification. The HAM10000 dataset was used for implementing, training, and evaluating the proposed and Transfer Learning (TL) models such as ResNet, AlexNet, and VGG16. During the validation and training stages, the performance of the four networks was evaluated by comparing their accuracy and loss. The proposed method outperformed the competing models with an average accuracy score of 98.19%. Our proposed methodology was validated against existing state-of-the-art algorithms from recent publications, resulting in consistently greater accuracies than those of the classifiers.

Benign fibrous histiocytoma of the lacrimal sac

Benign fibrous histiocytoma (BFH) is a tumor of mesenchymal origin, mostly seen in subcutaneous tissues, and it commonly affects males with a mean age of 55 years. We report a 60-year-old with lacrimal sac swelling that was recurrent. Initially, it started as the size of a black-eyed bean seed, which gradually progressed to the size of a small-sized peewee egg. She had complete excision of the mass with no bony erosions or intracranial extension. Histopathology revealed a BFH of the lacrimal sac. She is currently doing well.

Multiple dermatofibromas in a patient with Ehlers–Danlos syndrome: a case report

BackgroundDermatofibromas, also known as benign fibrous histiocytomas, are among the most common cutaneous soft-tissue lesions. Association of multiple dermatofibromas with some diseases was described and it has not been reported with Ehlers–Danlos syndrome before. We present a case with Ehlers–Danlos syndrome and multiple dermatofibromas.Case presentationAn 18-year-old Iranian woman presented with multiple purple nodules ranging from 0.5 to 1.5 cm in diameter, which were mobile and located on the proximal part of the lower limb. The dimple sign of these lesions was positive. During the physical examination, several features suggestive of Ehlers–Danlos syndrome were observed, including hyperextensibility and fragility of the skin, wide atrophic scars on the upper limb, hypermobility of joints and fingers, swan neck deformities of the digits, nodules on the knee, and striae alba on the leg. The patient was previously unaware of having Ehlers–Danlos syndrome. She had a history of asthma and atopic dermatitis. Family history was negative. A biopsy of the nodular lesions was performed, and the findings confirmed the diagnosis of dermatofibromas.ConclusionWe describe a patient with Ehlers–Danlos Syndrome who presented with multiple dermatofibromas. To our knowledge, this combination of findings is a previously unreported occurrence.

Clinicopathologic and molecular study of superficial CD34-positive fibroblastic tumours mimicking atypical fibrous histiocytoma (dermatofibroma).

Superficial CD34-positive fibroblastic tumour (SCD34FT) is an uncommon but distinctive low-grade neoplasm of the skin and subcutis that shows frequent CADM3 expression by immunohistochemistry (IHC). In this study, prompted by an index case resembling 'atypical fibrous histiocytoma (FH)' that was positive for CADM3 IHC, we systematically examined a cohort of tumours previously diagnosed as 'atypical FH' by applying CADM3 and fluorescence in situ hybridization (FISH) for PRDM10 rearrangement, to investigate the overlap between these tumour types. Forty cases of atypical FH were retrieved, including CD34-positive tumours (n = 20) and CD34-negative tumours (n = 20). All tumours were stained for CADM3. All CADM3-positive tumours were evaluated by FISH to assess for PRDM10 rearrangement. Eleven CD34-positive tumours (11/20, 55%) coexpressed CADM3 and were reclassified as SCD34FT. None (0/20) of the CD34-negative atypical FH were CADM3-positive. Reclassified SCD34FT (10/11) arose on the lower extremity, with frequent involvement of the thigh (n = 8). Features suggestive of atypical FH were observed in many reclassified cases including variable cellularity, spindled morphology, infiltrative tumour margins, collagen entrapment, epidermal hyperpigmentation, and acanthosis. Variably prominent multinucleate giant cells, including Touton-like forms, were also present. An informative FISH result was obtained in 10/11 reclassified tumours, with 60% (6/10) demonstrating PRDM10 rearrangement. A significant subset of tumours that histologically resemble atypical FH, and are positive for CD34, coexpress CADM3 and harbour PRDM10 rearrangement, supporting their reclassification as SCD34FT. Awareness of this morphologic overlap and the application of CADM3 IHC can aid the distinction between SCD34FT and atypical FH.

Intracerebral benign fibrous histiocytoma.

Benign fibrous histiocytoma (BFH) within the intracerebral region is remarkably rare. Our report details 2 cases of unusual BFH instances that exhibit no adhesion to the dura mater or cerebral falx, accompanied by a comprehensive literature review. While magnetic resonance imaging demonstrates specific characteristics for BFH, it does not readily differentiate BFH from more common brain neoplasms like gliomas and metastatic tumors. The definitive diagnosis of BFH depends primarily on histopathological and immunohistochemical examinations. Total surgical resection is considered an efficacious therapeutic approach, emphasizing the necessity for prolonged postoperative surveillance to detect any potential tumor recurrence or metastasis.

Differential diagnosis of primary mesenchymal neoplasms of the breast.

While the majority of breast neoplasms originate from epithelial cells, a rare part of them originate from mesenchymal breast tissue. This study aims to present the histomorphological and clinicoradiological features of our series of primary mesenchymal breast tumors and to discuss the features of these tumors in light of the literature. Cases diagnosed as primary mesenchymal breast tumor in breast resection materials evaluated in our center between 2010 and 2023 were included. Of the 26 tumors included, 57.7% were diagnosed as benign and 42.3% as malignant mesenchymal tumor. Cases diagnosed as benign mesenchymal tumor were hemangioma, lipoma, extra-abdominal fibromatosis, leiomyoma, angiofibroma, lipomatosis, benign fibrous histiocytoma and granular cell tumor. Histopathological study results were compatible with angiosarcoma in 5 (45.4%), undifferentiated sarcoma in 3 (27.3%), myxofibrosarcoma in 2 (18.2%) cases and rhabdomyosarcoma in 1 (9.1%) case. Primary breast sarcomas are rarely seen compared to benign mesenchymal tumors and constitute less than 0.1% of all malignant breast tumors. When histomorphological findings suggestive of a mesenchymal tumor are observed in breast specimens, sufficient sampling should be performed to exclude a possible phyllodes tumor, and clinicoradiological findings should be examined to exclude the possibility of a metastasis.

Primary Benign Fibrous Histiocytoma of the Tail of the Pancreas: Incidental Finding During Clinical Follow-Up of a Patient with Invasive Breast Carcinoma

Primary Benign Fibrous Histiocytoma of the Tail of the Pancreas: Incidental Finding During Clinical Follow-Up of a Patient with Invasive Breast Carcinoma

A Method of Skin Disease Detection Using Image Processing and Machine Learning

Skin conditions are prevalent health issues globally. The dangers posed by these infections are unseen, leading to physical discomfort and mental anguish. In severe cases, skin diseases can even progress to skin cancer. Consequently, the identification of skin diseases from clinical images remains a significant challenge in medical image analysis. Furthermore, manual diagnosis by medical professionals is time-consuming and subjective. Therefore, there is a need for automated skin disease prediction to expedite treatment planning for both patients and dermatologists. These studies presents a digital hair removal method and de-blurs or denoise the images. To extract essential patterns from the skin imagesand statistical features techniques are utilized. Two efficient machine learning algorithms, namely Support Vector Machine (SVM), and Convolutional Neural Network (CNN) classifiers, are employed with the extracted features to accurately classify skin images as melanoma (MEL), melanocytic nevus (NV), basal cell carcinoma (BCC), actinic keratosis (AK), benign keratosis (BKL), dermatofibroma (DF), vascular lesion (VASC), and Squamous cell carcinoma (SCC). The models are validated using the ISIC 2019 challenge and HAM10000 datasets, with SVM demonstrating slightly superior performance compared to the other classifiers. Furthermore, a comparison with state-of-the-art methods is conducted to evaluate the effectiveness of the proposed approach.

Intraosseous resection of bone tumors: our experience

Introduction. The effectiveness of efficient surgical interventions in patients with benign, borderline, and malignant bone tumors remains an important topic because such operations imply lower injury rate and volume of surgical intervention while being more physiological. In terms of radicality and consequently recurrence rates they are comparable to more traumatic surgeries such as segmental resections with various types of reconstructions (arthrodesis, endoprosthesis, auto- and allotransplantation using bone fragments, et al) and amputation.Aim. To analyze the results of intraosseous resection for benign, malignant, giant cell, and metastatic bone tumors.Materials and methods. Between 2015 and 2023, 45 interventions of intraosseous resection were performed in 44 patients: 19 (43 %) had enchondroma, 6 (14 %) – giant cell tumor, 4 (9 %) – fibrous dysplasia, 3 (7 %) – solitary bone cyst, 3 (7 %) – aneurysmal bone cyst, 2 (5 %) – chondromyxoid fibroma, 4 (9 %) – metastatic bone lesions, 1 (2 %) – osteoid osteoma, 1 (2 %) – benign fibrous histiocytoma, 1 (2 %) – chondrosarcoma G1 . Among them, 27 interventions were performed in combination with adjuvants (liquid nitrogen cryoablation, argon plasma coagulation, hydrogen peroxide, ethanol). In 24 patients, reconstruction was performed using lyophilized corpse bones, in 5 using autotransplant (fragments of the iliac crest), in 10 using plastic material (in 6 – polymethacrylate, in 4 – osseointegrative material “Rekost”), in 6 using xenoplastic material “Silorif.” Additionally, 16 surgeries were augmented with osteosynthesis (14 extramedullary and 3 intramedullary osteosyntheses).Results. Complications in the early postoperative period were observed in 3 (7 %) patients, in the late postoperative period in 2 (5 %) patients. At follow ups (between 2 and 97 months), 42 (95 %) patients did not have signs of recurrence. Musculoskeletal Tumor Society Score (MSTS) at these follow ups in recurrence-free patients was excellent (mean score – 93.6 %) and good (mean score – 77 %). Eastern Cooperative Oncology Group (ECOG) performance status also showed high functional potential of intraosseous resection: its mean value was 0.3.Conclusion. Use of intraosseous resection including augmentation with adjuvant measures, allowed to achieve excellent functional results in 42 (95 %) of patients with mean follow-up duration of 39.8 months. Fractures in 2 patients demonstrate the necessity of extramedullary osteosynthesis in surgeries on long bones experiencing high load irrespective of the volume of intervention. The obtained results show applicability and high effectiveness of intraosseous resection. For certain indications, it can be the treatment of choice.

SNC_Net: Skin Cancer Detection by Integrating Handcrafted and Deep Learning-Based Features Using Dermoscopy Images

The medical sciences are facing a major problem with the auto-detection of disease due to the fast growth in population density. Intelligent systems assist medical professionals in early disease detection and also help to provide consistent treatment that reduces the mortality rate. Skin cancer is considered to be the deadliest and most severe kind of cancer. Medical professionals utilize dermoscopy images to make a manual diagnosis of skin cancer. This method is labor-intensive and time-consuming and demands a considerable level of expertise. Automated detection methods are necessary for the early detection of skin cancer. The occurrence of hair and air bubbles in dermoscopic images affects the diagnosis of skin cancer. This research aims to classify eight different types of skin cancer, namely actinic keratosis (AKs), dermatofibroma (DFa), melanoma (MELa), basal cell carcinoma (BCCa), squamous cell carcinoma (SCCa), melanocytic nevus (MNi), vascular lesion (VASn), and benign keratosis (BKs). In this study, we propose SNC_Net, which integrates features derived from dermoscopic images through deep learning (DL) models and handcrafted (HC) feature extraction methods with the aim of improving the performance of the classifier. A convolutional neural network (CNN) is employed for classification. Dermoscopy images from the publicly accessible ISIC 2019 dataset for skin cancer detection is utilized to train and validate the model. The performance of the proposed model is compared with four baseline models, namely EfficientNetB0 (B1), MobileNetV2 (B2), DenseNet-121 (B3), and ResNet-101 (B4), and six state-of-the-art (SOTA) classifiers. With an accuracy of 97.81%, a precision of 98.31%, a recall of 97.89%, and an F1 score of 98.10%, the proposed model outperformed the SOTA classifiers as well as the four baseline models. Moreover, an Ablation study is also performed on the proposed method to validate its performance. The proposed method therefore assists dermatologists and other medical professionals in early skin cancer detection.

Recurrent benign fibrous histiocytoma of the bone benefits from denosumab followed by malignant transformation: a case report

Benign fibrous histiocytoma of the bone (BFHB) is a rare mesenchymal tumor, representing less than 1% of all benign bone tumors. This controversial entity is characterized by a mixture of fibroblasts arranged in a storiform pattern, varying amounts of osteoclast-type giant cells and foamy macrophages. Curettage or simple resection is usually curative. However, it was reported that up to 11% of the patients suffer from relapse. Here, we report a case of malignant transformation of BFHB after long-lasting disease stabilization under denosumab therapy.

Dermatofibromas on the Foot and Ankle: A Clinicopathologic Characterization of 31 Cases.

Dermatofibroma (DF) is a common benign soft-tissue tumor. It occurs anywhere on the body but is commonly seen on the upper and lower extremities. It is frequently found in young to middle-aged adults and predominantly in females. Thirty-one patients with DF on the foot and ankle diagnosed and treated during a 6-year period were characterized. The patients (16 males, 15 females) were aged 7 to 75 years (average, 55 years). Clinically, 17 patients noted painful symptoms, and 14 were painless. Grossly, DF manifested as a raised red, pink, tan, or skin-colored soft mass. The tumor size ranged from 0.3 to 1.5 cm (average, 0.67 cm in diameter). Twenty-six DFs (84%) were localized on the dorsal surface of the foot and ankle, and five (16%) were found on the plantar aspect. Eighteen patients were treated by surgical excision of the tumor (>0.5 cm), and 13 patients had observational follow-up after punch biopsy due to the small size (≤0.5 cm) and benign nature of these lesions. Further follow-up found that only one patient (3.2%) had a local recurrence, 37 months after surgical excision, which was completely reexcised. Histologically, DF is characterized by proliferation of spindle fibroblasts and histiocytes, in a vague fascicular pattern, and thickened collagen bundles. Dermatofibroma on the foot and ankle predominantly occurs in patients in their 50s, without a preponderance by sex. It needs to be differentiated from other benign and malignant tumors with histologic analysis and immunostaining with factor XIIIa, CD68, and other biomarkers. Treatment options include either surgical excision or observational follow-up after biopsy, depending on the clinical characteristics and effect on functional activity.

A study of collagen refractility in dermatofibroma and dermatofibrosarcoma protuberans using diffractive microscopy.

Diffractive microscopy creates contrast within samples that are otherwise uniform under bright light. This technique can highlight subtle differences in refractive indices within birefringent samples containing varying amounts of mature collagen. Dermatofibroma (DF) and dermatofibrosarcoma protuberans (DFSP) possess differences in their mature collagen content and, therefore, may be distinguishable using diffractive microscopy. Two hundred forty-two DF and 85 DFSP hematoxylin-eosin (H&E)-stained specimens were analyzed using diffractive microscopy. Data regarding the distribution pattern and strength of refractility was recorded. DFSP was more frequently found to be focally, weakly, or non-refractile (82.9%; n = 68) under diffractive microscopy, while DF more often showed diffusely bright refractility (52.9%; n = 128). DFSP samples with diffuse refractility in portions of the lesion (17.1%; n = 14) also exhibited a unique checkerboard pattern distinct from that which was seen in DF samples. The absence of diffuse refractility was more closely associated with DFSP, as was the presence of a unique checkerboard diffraction pattern. Despite high sensitivity (Sn = 82.9%), absent refractility was not a specific test (Sp = 52.9%), with 47.1% (n = 114) of DF samples sharing this feature. The distinction between DF and DFSP is often diagnosed using H&E alone. In difficult cases, examination of collagen under diffractive microscopy may be useful in distinguishing DFSP from DF and provide an alternative cost-effective tool to immunohistochemical staining.

Abstract B064: Racial disparities in bone and soft-tissue sarcomas: An analysis of the Surveillance, Epidemiology, and End Results program

Abstract Introduction Bone and soft-tissue sarcomas comprise a broad yet heterogenous group of malignancies, separately classified into at least 70 different histological diseases. In the United States, approximately 15,000 cases of bone and soft-tissue sarcomas are annually diagnosed, roughly representing 1% of all incident cancer diseases. Health disparities exist for cancer patients of different racial identities, but research on patients with soft-tissue and bone sarcomas is still debatable. This analysis elucidates racial discrepancies in epidemiological measures among patients with such diseases. Methods The Surveillance, Epidemiology, and End Results database was queried between 2000 and 2020 for patients with bone or soft-tissue sarcomas. Metrics, consisting of prevalence, incidence, and incidence-based mortality rates, as well as case-fatality ratios were computed. Multivariate survivorship analyses controlling for age, sex, race, tumor size, stage, and grade were performed to identify independent predictors of survival. Results The most and least frequently diagnosed subtypes of bone and soft-tissue sarcomas were leiomyosarcoma and lymphangiosarcoma with an average of 889.6 and 1.3 cases per year, respectively. Malignancies were all primarily identified in White patients compared to subjects of other races. From 2000 to 2020, the prevalence of fibrosarcoma significantly increased for non-White and non-Black individuals and the prevalence of dermatofibrosarcoma decreased only for White individuals (both, p<0.05). Incident cases of dermatofibrosarcoma decreased for White patients and the general population but increased for Black patients and those of other races (p<0.001). Incident cases of synovial sarcoma, on the other hand, declined only among Black individuals (p<0.001). Incidence-based mortality rates increased significantly among patients with almost all bone and soft-tissue sarcomas but declined among Black individuals with fibrous histiocytoma (both, p<0.001). Multivariate survivorship analysis showed that Black individuals experienced worse survival compared to White individuals with clear cell sarcoma, hemangiosarcoma, leiomyosarcoma, and synovial sarcoma. Individuals of other races with clear cell sarcoma, hemangiosarcoma, and leiomyosarcoma experienced worse survival compared to White patients with these diseases. Conclusion Current literature has not delineated the impact of demographic factors like race and ethnicity on prevalence, incidence, mortality, and survivorship of patients with bone and soft-tissue sarcomas. Racial discrepancies exist among patients with various subtypes of bone and soft-tissue sarcoma. More exploration into social determinants of health is necessary to understand how race plays a role in the epidemiology of these cancers. Citation Format: Marc El Beaino, Rachel Baum, Karim Masrouha, Patrick P. Lin. Racial disparities in bone and soft-tissue sarcomas: An analysis of the Surveillance, Epidemiology, and End Results program [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B064.

168 Cases of aneurysmal dermatofibroma and 29 cases of hemosiderotic dermatofibroma: A clinicopathologic study.

Aneurysmal dermatofibroma (ADF) and hemosiderotic dermatofibroma (HDF) are rare variants of dermatofibroma (DF) characterized by distinct histologic features. While HDF is traditionally considered a precursor to ADF, supporting evidence is limited, and the etiology remains unclear. A retrospective analysis of 2128 DF cases (2016-2019) was conducted to investigate the clinicopathologic characteristics of ADF, HDF, and other DFs. Histopathologically diagnosed DF cases were examined for ADF and HDF. Univariate analyses were performed to compare clinicopathologic features. Among the cases, 168 (7.9%) were ADF and 29 (1.4%) were HDF. Aneurysmal dermatofibroma and HDF shared several common characteristics, including lower occurrence in females, larger size, and increased cellularity (all P < .0001). Notably, 29% of ADFs lacked hemosiderin deposition. Aneurysmal dermatofibroma primarily manifested on exposed areas (face and forearm, both P < .001). In contrast, 41% of HDFs occurred on the lower leg (P = .018), and all lower leg HDFs exhibited signs of venous stasis, distinguishing them from other HDFs (P < .0001). Our findings indicate a potential close relationship between ADF and HDF. Contrary to conventional beliefs, we also presented the possibility of ADF progressing into HDFs. Physical trauma may induce ADF, and HDFs may emerge from ADFs in conjunction with venous stasis in the lower extremities.

Classification of Skin Lesion Images Using Artificial Intelligence Methodologies through Radial Fourier–Mellin and Hilbert Transform Signatures

This manuscript proposes the possibility of concatenated signatures (instead of images) obtained from different integral transforms, such as Fourier, Mellin, and Hilbert, to classify skin lesions. Eight lesions were analyzed using some algorithms of artificial intelligence: basal cell carcinoma (BCC), squamous cell carcinoma (SCC), melanoma (MEL), actinic keratosis (AK), benign keratosis (BKL), dermatofibromas (DF), melanocytic nevi (NV), and vascular lesions (VASCs). Eleven artificial intelligence models were applied so that eight skin lesions could be classified by analyzing the signatures of each lesion. The database was randomly divided into 80% and 20% for the training and test dataset images, respectively. The metrics that are reported are accuracy, sensitivity, specificity, and precision. Each process was repeated 30 times to avoid bias, according to the central limit theorem in this work, and the averages and ± standard deviations were reported for each metric. Although all the results were very satisfactory, the highest average score for the eight lesions analyzed was obtained using the subspace k-NN model, where the test metrics were 99.98% accuracy, 99.96% sensitivity, 99.99% specificity, and 99.95% precision.

Connexin 43 in Dermatofibroma and Dermatofibrosarcoma Protuberans: Diagnostic, Pathogenic, and Therapeutic Implications.

Connexins play a crucial role in the formation of gap junctions that connect cells to each other, as well as cells to the surrounding environment. In recent years, connexin 43 has been extensively studied in various human tumors. In this study, we conducted an immunohistochemical analysis to evaluate the expression of connexin in 16 dermatofibromas (DFs) and 13 dermatofibrosarcoma protuberans (DFSP). Connexin was diffusely expressed in the cytoplasm of all DFs with moderate or strong intensity, whereas all DFSPs showed negative staining. In addition to its diagnostic implications, the loss of Cx43 may elucidate the invasive capacity of DFSP and offer a potential avenue for future therapeutic interventions.

"Unusual Presentation of Epitheloid Dermatofibroma- Rare Case Report".

Dermatofibroma is a commonly occurring cutaneous entity usually centered within the skin's dermis. Dermatofibromas are referred to as benign fibrous histiocytomas of the skin, superficial/cutaneous benign fibrous histiocytomas, or common fibrous histiocytoma. These mesenchymal cell lesions of the dermis clinically are firm subcutaneous nodules that occur on the extremities in the vast majority of cases and may or may not be associated with overlying skin changes.A 20years old male presented to ENT OPD, at a private hospital, with complaints of a huge mass over right side of face since 15years, which was slowly growing and not associated with pain. On clinical examination, hard, non tender, lobulated cauliflower like mass located over right side of face extending from right side temporal region to upper border of mandible from superior to inferior. From anterior to posterior it was extending from lateral 1/3rd of forehead and covering lateral canthus of right eye upto right side tragus. We have taken incisional biopsy which was suggestive of dermatofibroma. Then surgery was performed with patient's consent. Excision with 1cm free margin was done. Raw area was covered with full thickness skin grafting and advancement flap. We found no recurrence till date. Dermatofibroma in the head and neck region is less common and often present a difficult differential diagnosis like Dermatofibrosarcoma protuberans, Kaposi Sarcoma, Basal cell carcinomas. The aim of case report is to represent case of dermatofibroma of epitheloid variety which is unusual in size.

Dermatofibroma Versus Dermatofibrosarcoma Protuberans: A Nuclear Morphology Study.

The locally invasive soft-tissue sarcoma, dermatofibrosarcoma protuberans (DFSPs), shares certain histologic features of the much more common and benign dermatofibroma (DF). While immunohistochemical stains, specifically cluster of differentiation 34 and Factor XIIIa, can be used to distinguish the 2 entities using microscopy, these markers are not entirely sensitive nor specific. Three-dimensionally, DFSP nuclei resemble a "puck" or "coin"-like shape. As hematoxylin/eosin-stained slides are prepared, these "puck" nuclei are fixed in an infinite number of orientations depending on their current position in rotation about their axes within the tumor cells. Under histological examination, this random nuclear positioning produces the appearance of 2 predominate morphologies: an ovoid "disk" shape (en face) and a narrow spindled shape (side view), which distribute in a roughly 50:50 ratio throughout the tumor sample slide. Nuclear morphology was analyzed in 324 DFSP and DF samples at high magnification (×400) to determine the presence or absence of a predominant morphology in which nuclei appear to alternate between an ovoid (en face) and spindled (side view) throughout most of the tumor sample. An alternating ovoid-spindled nuclear morphology was the predominant cytology in 98% of DFSP and was not predominant in 100% of DF samples (P < 0.001). This morphology was found to be highly specific (Sp = 1) and sensitive (Sn = 0.98) for DFSP. This unique nuclear morphology may be a more sensitive and specific diagnostic tool in identifying DFSP from DF in comparison with costly immunohistochemical stains.

Increased Occurrence of Cutaneous Leiomyomas and Dermatofibromas in Patients with Uterine Leiomyomas without Fumarate Hydratase Gene Mutations.

Leiomyomas are smooth muscle-derived benign neoplasms that can affect all organs, most frequently in the uterus. Fumarate hydratase gene (FH) mutation is characterised by an autosomal dominant disease with increased occurrence of renal tumours, but also by cutaneous (CLs) and uterine leiomyomas (ULs). So far, an increased occurrence of skin tumours in non-mutated patients with ULs has not been verified. To this aim, a case-group of women who were FH non-mutated patients surgically treated for ULs (n = 34) was compared with a control-group (n = 37) of consecutive age-matched healthy women. The occurrence of skin neoplasms, including CLs and dermatofibromas (DFs), was evaluated. Moreover, the microscopic features of FH non-mutated skin tumours were compared with those of an age-matched population group (n = 70) who presented, in their clinical history, only one type of skin tumour and no ULs. Immunohistochemical and in vitro studies analysed TGFβ and vitamin D receptor expression. FH non-mutated patients with ULs displayed a higher occurrence of CLs and DFs (p < 0.03 and p < 0.001), but not of other types of skin tumours. Immunohistochemistry revealed a lower vitamin D receptor (VDR) expression in CLs and DFs from the ULs group compared with those from the population group (p < 0.01), but a similar distribution of TGFβ-receptors and SMAD3. In vitro studies documented that TGFβ-1 treatment and vitamin D3 have opposite effects on α-SMA, TGFβR2 and VDR expression on dermal fibroblast and leiomyoma cell cultures. This unreported increased occurrence of CLs and DFs in FH non-mutated patients with symptomatic ULs with vitamin D deficiency suggests a potential pathogenetic role of vitamin D bioavailability also for CLs and DFs.