Subcutaneous Angiofibroma of the Ankle: A Rare, Undescribed Clinical Entity

Soft tissue angiofibroma is a pathology consisting of a benign fibrous vascularized tumor that mimics low-grade sarcoma. Such tumors frequently arise in the extremities, more commonly in the lower extremities, presenting as a slow-growing, painless swelling. Females are more commonly affected than males. We present the case of a 42-year-old male with a slow-growing, painless mass on the extensor aspect of his left foot. Differential diagnoses considered were soft tissue fibrosarcoma, liposarcoma, and sebaceous cysts. Surgical excision of the tumor was done, and upon histopathology, there were multiple lobules with well-circumscribed, alternating areas of collagenous and myxoid tissues. There was a prominent small vascular network with uniformly arranged spindle cells consisting of pale eosinophil-rich cytoplasm and small ovoid nuclei, fine chromatin, and an indistinct nucleolus. There are not many reported cases of this clinical entity, and every new case reported brings light to the pathology and progression of this tumor. Understanding this pathology is necessary since it mimics many other skin and soft tissue tumors.

Calcifying Nested Stromal-Epithelial Tumor: An Extremely Rare Hepatic Tumor

Calcifying nested stromal-epithelial tumor is a rare hepatic malignancy with approximately 50 cases reported in the literature. Its clinical presentation is nonspecific, and the diagnosis is mainly based on histology which shows nests of spindle and epithelioid cells along with a desmoplastic myofibroblastic stroma containing variable calcification and ossification. In this report, we present a case of a 24-year-old woman with a history of abdominal pain, distension, and dyspepsia. She had a palpable liver with normal liver function test results. Serum alpha-fetoprotein levels were within normal range, and serologies for hepatitis B and C virus remained negative. Radiological investigations (magnetic resonance imaging and computed tomography) showed a large, right hepatic lobe mass with tumor invasion into the right posterior portal vein, but the 2 modalities could not characterize the lesion. Finally, an ultrasound-guided biopsy of the liver lesion provided the diagnosis of calcifying nested stromal-epithelial tumor. The tumor was resected successfully.

Primary Pulmonary Carcinomas with Spindle and/or Giant Cell Features: A Review with Emphasis in Classification and Pitfalls in Diagnosis

Primary carcinomas of the lung are vastly represented by the conventional types of adenocarcinomas or squamous cell carcinomas. However, there are other types of non-small cell carcinomas that although uncommon represent a meaningful group that often pose a problem not only in diagnosis but also in classification. Spindle cell and/or giant cell carcinomas, although uncommon represent an important group of primary lung carcinomas. Important to highlight is that current criteria are rather ambiguous and likely not up to date, which renders the classification of these tumors somewhat more obscure. In addition, with the daily use of immunohistochemical stains, the classification of these tumors may also pose a different problem in the proper allocation of these tumors. Proper classification is highly important in the selection process that takes place using such material for molecular analysis. The current molecular characteristics of these tumors are limited and lack more in-depth studies and analyses that can provide specific targets for the treatment of patients with these tumors. The current review attempts to highlight the shortcomings in the current classification and definitions of these neoplasms as well as the more current view regarding these tumors when the use of immunohistochemical stains is employed.

Fibroblastic osteosarcoma: A perplexing entity

Osteosarcoma (OS), also referred to as osteogenic sarcoma, is the most common primary malignant tumour affecting long bones, characterised by the proliferation of osteoblastic precursor cells and the production of osteoid or immature bone. OSs of the head and neck region have unique biology, exhibiting a clinical behaviour and a natural history that are distinct from OSs of the trunk and extremities. Similarly, their radiological appearance and histological growth pattern can be quite diverse proving to be a challenge to histopathologists to arrive at a diagnosis. Hence, OSs of the jaw remain enigmatic, and a number of difficulties related to their diagnosis and treatment are yet to be resolved. This article reports on a case of advanced OS of the mandible in a 45-year-old woman who came for the evaluation of swelling. This case illustrates the various modalities of diagnosis, such as radiology, histopathology and immunohistochemistry for the confirmation of the variants of OS, leading to an enormously improved quality of life by offering an improved opportunity for cure and treatment.

Pancreatic acinar cell carcinoma with pleomorphic and spindle cells: An autopsy-proven case

Pancreatic acinar cell carcinomas are glandular and have amphophilic/eosinophilic cytoplasm, presenting acinar, solid, and trabecular structures. Unusual histological features of acinar cell carcinoma are known, such as oncocytic, pleomorphic, spindle, and clear cell variants, but their clinical significance has not been well described. A man in his 70s was referred to our hospital because of elevated serum pancreatic enzymes. Contrast-enhanced abdominal computed tomography revealed slight swelling of the pancreatic head and suspension of the main pancreatic duct in the pancreatic body. He died only 14 days after admission. Gross findings at autopsy showed an ill-defined tumor located in the pancreatic head, involving the gastric and duodenal walls. Peritoneal dissemination, liver metastases, and lymph node metastases were also observed. Microscopically, tumor cells had moderate-to-severe nuclear atypia and amphophilic cytoplasm showing pleomorphism, and diffusely proliferated in solid pattern without lumina, were admixed with spindle cells. Immunohistochemically, tumor cells including pleomorphic and spindle cells were positive for B-cell lymphoma/leukemia 10 and trypsin. Consequently, the diagnosis was pancreatic acinar cell carcinoma with pleomorphic and spindle cells. We encountered a rare variant of pancreatic acinar cell carcinoma with pleomorphic and spindle cells. Clinically, our case showed rapid progression.

Bronchial Schwannoma Incidentally Discovered via Bronchoscopy: A Case Report

Bronchial schwannomas are rare tumors that arise from Schwann cells and account for a very small percentage of primary lung tumors. This case report describes a rare incidental finding of a bronchial schwannoma discovered in the left lower lobe secondary carina via bronchoscopy in a 71-year-old female who presented with minimal symptoms.

Dermatofibrosarcoma Protuberans Over Right Lumbar Region: A Case Report

Dermatofibrosarcoma protuberans is a rare, low-grade dermal soft-tissue tumor with a high propensity for recurrence but a low propensity for metastatic spread. It mostly affects the head, neck, proximal extremities, and trunk. We report a case of dermatofibrosarcoma protuberans over the right lumbar region. The patient presented with swelling in the right lumbar region measuring 3 cm × 3 cm. The local region ultrasonography (USG) revealed a well-defined hypoechoic lesion in the subcutaneous area. The patient was provisionally diagnosed with a peripheral nerve sheath tumor under evaluation. USG-guided fine needle aspiration cytology (FNAC) suggested a spindle cell tumor. Wide local excision of the tumor was performed. Monomorphic spindle cells in a storiform pattern were observed by histological evaluation. The neighboring adipose tissue was invaded by the tumor cells in a honeycomb-shaped pattern. The histological features were suggestive of Dermatofibrosarcoma Protuberans. Due to the high likelihood of recurrence, it is crucial to monitor these patients for an extended period of time.

Genome-wide association meta-analysis identifies 48 risk variants and highlights the role of the stria vascularis in hearing loss

Hearing loss is one of the top contributors to years lived with disability and is a risk factor for dementia. Molecular evidence on the cellular origins of hearing loss in humans is growing. Here, we performed a genome-wide association meta-analysis of clinically diagnosed and self-reported hearing impairment on 723,266 individuals and identified 48 significant loci, 10 of which are novel. A large proportion of associations comprised missense variants, half of which lie within known familial hearing loss loci. We used single-cell RNA-sequencing data from mouse cochlea and brain and mapped common-variant genomic results to spindle, root, and basal cells from the stria vascularis, a structure in the cochlea necessary for normal hearing. Our findings indicate the importance of the stria vascularis in the mechanism of hearing impairment, providing future paths for developing targets for therapeutic intervention in hearing loss.

Cytologic features of reactive fibroplasia in cutaneous and subcutaneous lesions of dogs: A retrospective study

BACKGROUND

Determining reactive fibroplasia from primary neoplastic proliferation can be difficult using the cytologic features of spindle cells.

OBJECTIVES

This study aimed to describe qualitative features of benign reactive spindle cells and provide a diagnostic tool to distinguish between fibroplasia and soft tissue sarcoma.

METHODS

Cytologic samples from cutaneous lesions with histopathologically confirmed fibroplasia were reviewed and compared with cytologic samples from confirmed low-grade soft tissue sarcomas. The samples were obtained from the Archive of the Laboratorio Veterinario Bresciano (Brescia; Italy).

RESULTS

A total of 25 cytologic samples retrieved from the database fit the selection criteria. For comparison, 25 cytologic samples of histopathologically confirmed soft tissue sarcomas with secondary inflammation were obtained and reviewed from the same database. A low number of singularly distributed spindle cells with mild features of atypia and a high ratio of inflammatory to spindle cells was observed in confirmed cases of fibroplasia.

CONCLUSIONS

Low cellularity, individualized spindle cells, and an increased inflammatory-to-spindle cell ratio were more indicative of fibroplasia than sarcoma.

Perivascular Epithelioid Cell Tumor of the Buttock Region

Perivascular epithelioid cell neoplasms, also known as PEComas, are a group of rare mesenchymal tumors that have a perivascular distribution and have no known counterpart to normal cells. The PEComa grouping includes angiomyolipomas, lymphangioleiomyomatoses, clear cell (sugar) tumors at extrapulmonary and intrapulmonary sites, clear cell myomelanocytic tumor of the falciform ligament/ligamentum teres among others. These rare tumors most commonly arise in the uterus. Here, we present an unusual case of malignant PEComa arising in the buttock region.

Inflammatory myofibroblastic tumor of gingiva in a patient with constitutional growth delay: A rare case report

Several disorders related to growth and development affect children during their early stages of life. One rare disorder that affects about 15% of children is constitutional growth delay (CGD). Its results in the affected individuals appear unusually short and young for their age. The individuals are otherwise normal and appear as their normal counterparts as age increases. Inflammatory myofibroblastic tumor (IMT) is a rare soft-tissue tumor that commonly affects the lungs, liver, and gastrointestinal tract. The occurrence of this tumor outside the aforementioned areas is very rare. It resembles a neoplastic tumor clinically and histologically. It is also referred to as inflammatory pseudotumor. Here, we report the case of an individual with CGD who also had an IMT involving the mandibular left canine region.

A Rare Incidence of Metachronous Neurovascular Lesions in a Child

Neurofibroma is an uncommon benign tumor arising from nerve sheath fibroblasts. The diagnosis of solitary lesions becomes difficult in patients who do not have any family history of neurofibroma. An intra-oral solitary neurofibroma comprises 6.5% of reported cases of neurofibroma. Few cases of intraosseous solitary neurofibroma have been published as per literature. Treatment-surgical resection of tumor has an excellent prognosis with extreme rare malignant transformation which is more commonly seen in neurofibromatosis. A periodic follow-up is necessary in solitary tumors to rule out syndromic cases. Leiomyoma is a benign tumor of smooth muscle origin, which is usually diagnosed in the gastrointestinal tract, uterus, and skin. The most effective treatment for solid, vascular, and epithelioid angioleiomyomas is surgical resection along with tumor capsule. Here we report an uncommon occurrence of multiple benign tumors in a pediatric patient.

Lesion-targeted cytology to improve cytological sampling for atypical polypoid adenomyomas of the uterus: A case series and review of the literature

OBJECTIVE

Atypical polypoid adenomyomas (APAs) are uncommon tumours consisting of atypical endometrioid glands and fibromyomatous stroma. Identifying the biphasic nature of atypical glandular components and spindle mesenchymal components without atypia is crucial for the cytological diagnosis of APA. We investigated the utility of lesion-targeted cytology (LTC) to directly collect firm spindle components.

METHODS

We recruited seven consecutive surgical patients who underwent cytological examinations before surgery and were diagnosed with APA on postoperative histological examinations. Cytological smears were obtained by routine sampling in five cases and by targeted sampling using transvaginal ultrasonography, that is, LTC, in two cases. We retrospectively analysed the cytological findings from our cases and compared them to those of APA cases previously reported in the English literature.

RESULTS

Among 5/7 cases that involved routine cytological sampling, normal cytological findings were found in 2 and atypical glandular cells were found in 3, but spindle cells from mesenchymal components were not detected. In contrast, among 2/7 cases in which sampling involved LTC, spindle cells without atypia, in addition to atypical glandular cells were found.

CONCLUSIONS

Lesion-targeted cytology is useful to assess mesenchymal components of APAs and may improve the cytological diagnosis of APA.

Giant cell-rich osteosarcoma - A rare case

Giant cell-rich osteosarcoma (GCRO) is an exceedingly rare histological variant of conventional primary osteosarcoma. It constitutes about 1%-3% of all osteosarcomas, and is extremely uncommon in the maxillofacial region. The unusual histopathological appearance and the rarity of the lesion poses a great diagnostic challenge. This article aims to present a rare case of GCRO involving the mandible in a 52-year-old male patient.

Cervical Lymph Node Schwannoma-An Unexpected Diagnosis

Introduction:

Schwannomas—Schwann cells–originating tumors—may develop in many locations. However, primary schwannomas arising within lymph nodes are extremely rare, with only a few cases described to this date in the English literature. For the intranodal location, most of the cases are described in the abdominal cavity. In these cases, clinicians may consider and check for familial disorders, such as neurofibromatosis type 2 (NF2) and schwannomatosis also called neurofibromatosis type 3. Schwannomas are benign neoplasms. Histologically, differential diagnosis for spindle-cell lesions in lymph nodes is important and must be done carefully, mainly because they may be attributable to metastatic disease. We report a case of a primary schwannoma arising in a cervical lymph node.

Background:

Primary schwannomas arising within lymph nodes are extremely rare, with only a few cases reported. Since they are benign neoplasms, the differential diagnosis with other intranodal spindle cell lesions, mostly malignant, is important.

Methods:

An asymptomatic 69-year-old woman, previously submitted to left hemithyroidectomy for a benign folicular nodule, underwent thyroidectomy totalization following the identification of a large thyroid nodule in routine evaluation.

Results:

Gross and microscopic examination and ancillary studies were consistent with the diagnosis of intranodal schwannoma. The patient had acquired bilateral hypoacusia. Therefore, type 2 neurofibromatosis was considered and vestibular schwannomas ruled out.

Conclusion:

Herein, we present the second case of a primary schwannoma in a cervical lymph node reported so far. The relevance of the differential diagnosis is highlighted.

Solitary fibrous tumor of the kidney: Magnetic resonance imaging characteristics in 4 patients

To investigate the characteristics of magnetic resonance image (MRI) in solitary fibrous tumor (SFT) of the kidney.MRI findings and clinical features of SFT of the kidney in 4 patients (2 men and 2 women with a mean age of 37.8 ± 8.7 years) were reviewed retrospectively. All patients were scanned by a 3.0-T magnetic resonance (MR) imaging system and the lesions were detected with emphasis on size, shape, location, margin, presence of pseudocapsule, signal intensity, degree of MR enhancement, and apparent diffusion coefficient (ADC).The 5 tumors from 4 patients were located in renal parenchyma (n = 1), renal pelvis (n = 3), and renal capsule (n = 1). On MRIs, the tumors were round (n = 1) or oval-shaped (n = 4), and presented pseudocapsule (n = 2) and well-circumscribed margins (n = 3) can be found. On T2-weighted images (T2WIs), solid components of the tumor presented homogeneously mild hypointensity or isointensity (n = 4) compared with the renal cortex. On diffusion-weighted images (DWIs), the lesions showed normal or mild hyperintensity (n = 4) with mean ADC of 1.687 × 10 mm/s. On dynamic contrast-enhanced MRIs, all lesions showed progressively mild enhancement. In the follow-up of 24 to 36 months after the surgery, 3 patients survived and 1 deceased.The SFT of the kidney appeared as a circle or oval and presented homogeneously mild hypointensity or isointensity on T2WIs, hyperintensity on DWIs, and progressively mild enhancement on DCE MRIs.

Ectopic hamartomatous thymoma (biphenotypic branchioma): A case report and review of the literature

RATIONALE

Ectopic hamartomatous thymoma is a very rare soft tissue neoplasm that commonly occurs in the lower neck of adult men.

PATIENT CONCERNS

A 32-year-old male presented 1-year history of the tumor lying in left supraclavicular fossa.

DIAGNOSES

Initial consideration of ultrasound and computed tomography was lipoma. After the operation, the pathologist diagnosed it as Ectopic Hamartomatous Thymoma.

INTERVENTIONS

A complete resection was performed.

OUTCOMES

To date, the patient had no evidence of metastasis or recurrence for 26 months after the operation.

LESSONS

Ectopic hamartomatous thymoma is rare. The mastery of the clinical and pathological features of the disease will contribute to the rapid diagnosis and treatment of the disease. In addition, it can be considered to update the name to "biphenotypic branchioma" in order to avoid conceptual confusion.

Differential Organ-targeting and Cellular Characteristics of Metastatic Human Pancreatic Cancer Cell Lines in Mouse Models

BACKGROUND/AIM

The lethal characteristic of pancreatic cancer is metastasis which is recalcitrant to currently-used chemotherapy. Our aim was to understand metastasis at the cellular level. We previously reported that multi-nucleate cells or spindle cells were more prominent in pancreatic cancer metastasis than in the primary tumor. In the present report, we investigated four representative human pancreatic cell lines for differences in cell morphology between the primary tumor and various metastatic organ targets for each cell line.

MATERIALS AND METHODS

Human pancreatic cancer cell lines AsPC-1, Panc-1, KP2 and KP3 were used. Pancreatic cancer cells were injected into spleen of nude mice resulting in experimental metastasis to various organs which were observed at the cellular level when the organs were placed into culture.

RESULTS

AsPC-1 and KP2 pancreatic cells formed many experimental liver metastases, in contrast to Panc-1 and KP3. Lung metastasis was only observed for AsPC-1. In the cultures established from the primary and metastatic tumors, multi-nucleate cells were found to be more prominent in the metastasis of the pancreatic cell lines with frequent metastasis, AsPC-1 and KP2. Spindle-like cells were observed prominently in AsPC-1 lung metastasis.

CONCLUSION

Human pancreatic cancer cell lines have differential metastatic characteristics with regard to target organs and cell-morphology changes. Multi-nucleate and spindle cells may play an important role in pancreatic cancer metastasis to the liver and lung, respectively.

Spindle cell subtype of pulmonary clear cell tumor with prominent calcification and malignant potential

Perivascular epithelioid cell tumor of the lung, also known as clear cell “sugar” tumor, is a rare benign tumor arising from perivascular epithelioid cells. Herein, we present a case of spindle cell subtype of pulmonary perivascular epithelioid cell tumor with prominent calcification and malignant potential in a 49‐year‐old woman. Histologically, the striking feature of this lesion was attributed to the presence of spindle cells arranged in a diffuse pattern, which is a pitfall for diagnosis. However, some of the lesion contained polygonal tumor cells with clear abundant cytoplasm surrounded by thin‐walled vascular spaces. The size of the tumor and its Ki‐67 index suggested malignant potential, and calcification was another rare characteristic. Immunostaining indicated that the tumor cells were positive not only for HMB‐45 and Melan A, but also for CD34 and CD1a. This tumor should be distinguished from tumors with rich spindle cells such as sarcoma, clear cell carcinoma, or metastatic tumors. The patient in this case was alive with no tumor recurrence or metastasis six months after lobectomy.

Primary Leiomyosarcoma of the Mandibular Alveolar Mucosa of a 12-Year-Old Child from Ethiopia: A Case Report

Leiomyosarcomas (LMSs) are rare malignant mesenchymal tumors which show smooth-muscle differentiation. Most LMSs involving the oral tissues primarily affect the maxillary sinus, the maxillary or mandibular bone. We present a case of LMS of the mandibular alveolar mucosa, arising in a 12-year-old male child from Ethiopia. A malignant spindle cell-like neoplasm was diagnosed on clinical and radiographic findings as well as on incisional biopsy. The tumor was resected with wide margins. The following histopathologic examination with additional immunohistochemical studies secured the diagnosis LMS. Microscopically, the spindle-shaped tumor cells were arranged in an interlacing fascicular pattern and contained oval to elongated, blunt-ended (cigar-shaped) nuclei. The immunohistochemical examination showed immunoreactive tumor cells for vimentin, actin, desmin, and H-caldesmon, which is pathognomonic for LMS. Immunohistochemical studies are mandatory to differentiate the LMS from other similar spindle cell neoplastic lesions. Radical resection with safety margins and a lifelong periodic follow-up has to be recommended.

Neoplastic diseases of the spermatic cord: an overview of pathological features, evaluation, and management

Extracellular tumors found with the spermatic cord, known as neoplasms, are usually identified to be benign. However, the accurate and timely diagnosis of spermatic cord masses is highly crucial, especially when most results are often overlooked or unclear. In this review, we discuss the anatomy and embryology of the spermatic cord. Upon rooting these fundamental concepts, we discuss an array of benign and malignant neoplastic tumors, including their origin, pathological features, clinical evaluation and management, as well as other case-specific characteristics of unique presentation. Many of these neoplasms are based on local neurological, vascular, muscular, bone, soft tissue, or lymphatic origin, while others have metastasized from particular areas of the body.

Inflammatory myofibroblastic tumor of mandible: A rare case report and review of literature

Inflammatory pseudotumor is a term given to different neoplastic and nonneoplastic entities that have a common histological appearance, which comprises spindle cell proliferation with a prominent chronic inflammatory cell infiltrate. Inflammatory myofibroblastic tumor (IMT) is an uncommon lesion with distinctive clinical, pathological and molecular features and is considered to be pseudotumor for the past two decades due to its appearance. IMT is an intermediate soft tissue tumor which was first observed in lungs. It was named as IMT because it mimics a malignant neoplasm clinically, radiologically and histopathologically. The most common sites are lungs, liver and gastrointestinal tract. IMT in head and neck region is exceptionally rare and the sites reported include gingiva, tongue, hard palate, mandible, buccal mucosa and submandibular salivary gland. Till now, 8 cases of intramandibular IMT were reported. Here, we report an additional case of intramandibular IMT in a 20-year-old male patient.

High-grade undifferentiated pleomorphic sarcoma of the pelvis: A case report and review of literature

High-grade spindle cell sarcomas are rare undifferentiated pleomorphic cancers that present a treatment challenge to urological practices, especially when they present in the pelvis. We report a 46-year-old male patient who presented to our urology clinic with urinary retention after having a Foley catheter placed at an outlying facility. A voiding trial was attempted, but the patient failed this trial. This failure resulted in cystoscopy with bilateral retrograde pyelograms, which revealed a compressed bladder due to extrinsic compression. This finding had been evaluated with a computed tomography (CT) scan with and without intravenous contrast that showed a 14 cm pelvic mass with bladder displacement and compression. A fine needle aspiration was done at this outlying facility, prior to referral to our office, and it confirmed spindle cell pathology. The mass was surgically excised with the histology revealing a pelvic spindle cell sarcoma with positive surgical margins. Further, metastatic work-up with CT/positron emission tomography revealed bone and lung metastasis. The patient is currently undergoing chemotherapy and radiation. In this case study, we will review staging, management, differential diagnosis, chemotherapy, and radiation.

A rare spindle-cell variant of non-Hodgkin's lymphoma of the mandible

A 64-year-old male farmer presented with a rapidly progressive swelling of the left mandible since 6 months. The swelling was firm to hard, diffuse, nontender, obliterating the vestibule with paresthesia of lower lip. The cone beam computed tomography imaging revealed an ill-defined, moth-eaten radiolucency with destruction of the buccal and lingual cortical plates. The rapid growth and aggressive behavior of the lesion coupled with guidance from the patient's previous reports from the incisional biopsy and fine needle aspiration cytology warranted a mandibular resection. Microscopic examination showed an encapsulated lesion situated in the connective tissue containing a mixture of proliferating spindle-shaped cells arranged in fascicles and round cells infiltrating into the connective tissue stroma and bone. The neoplastic cells exhibited atypical features such as pleomorphism, hyperchromatism and increased mitotic figures with noncleaved nuclei. A working diagnosis of a spindle-cell sarcoma was arrived at with various differentials provided such as fibrosarcoma, rhabdomyosarcoma, leiomyosarcoma, malignant peripheral nerve sheath tumor, Langerhans cell histiocytosis and lymphoma and stating the need for immunohistochemistry to subtype the tumor. The neoplastic cells were negative for Van Gieson's stain and Masson's trichrome. Immunohistochemical analysis performed using desmin, smooth muscle actin, S-100 and CD1a in a bid to determine the phenotype of the tumor and rule out the previously stated differentials were all negative for the lesion. Lymphoid markers such as leukocyte common antigen and CD20 (cluster differentiation marker for B-cells) showed positivity in spindle-shaped cells as well as round cells indicating the tumor to be a lymphoproliferative lesion of B-cell type. A final diagnosis of “spindle-cell variant of non-Hodgkin's lymphoma” was rendered based on the immunohistochemical profile.

Cytologic features of hepatic fibrosis in dogs: a retrospective study on 22 cases

INTRODUCTION

Liver cytology has diagnostic value for the identification of neoplastic and nonneoplastic hepatic diseases. However, so far the diagnosis of fibrotic changes has traditionally been restricted to histopathology.

OBJECTIVES

The aim of this study was to describe the cytologic features that may help in the recognition of hepatic fibrosis.

MATERIALS AND METHODS

Cytologic smears from the liver of dogs histologically diagnosed with hepatic fibrosis (Group A) were selected and compared to liver smears from dogs without hepatic fibrosis (Group B). A differential count of hepatocytes, spindle cells, mast cells, granulocytes, lymphocytes/plasma cells, and macrophages was documented for each case, and means for the fibrosis and nonfibrosis group were compared.

RESULTS

The relative and total numbers of spindle cells and mast cells were significantly higher in the fibrosis group than in the nonfibrosis group. The optimal cutoff point for the spindle cells to hepatocytes ratio was 0.107 (ie, one spindle cell per 10 hepatocytes), with 95.5% sensitivity and 100% specificity for the cytologic diagnosis of hepatic fibrosis. The optimal cutoff point for the ratio mast cells to hepatocytes was 0.04 (ie, 4 mast cells per 100 hepatocytes) with 86.4% sensitivity and 90% specificity.

DISCUSSION

The presence of relatively and absolutely increased numbers of spindle and mast cells in hepatic cytology provides a rational basis to identify fibrosis of hepatic parenchyma. Based on a reasonable sensitivity and specificity, the cytologic diagnosis of hepatic fibrosis seems feasible.

Lymphangioleiomyomatosis diagnosed by effusion cytology: A case report

Lymphangioleiomyomatosis (LAM) is a rare lung disease traditionally affecting women during their childbearing years. It can be sporadic or be associated with tuberous sclerosis syndrome. It is usually manifested in the lungs, kidneys, and/or lymphatic system. It consists of an overgrowth of abnormal smooth muscle-like cells, usually along the bronchovascular structures, resulting in the formation of cysts and the destruction of the lung parenchyma. We present the case of a 43-year-old woman with a history of pleural effusion and dyspnea. A computed tomographic scan revealed a mediastinal mass, chylothorax, and multiple pulmonary cysts. A diagnosis of LAM was rendered on a pleural fluid sample.

Cutaneous metastasis from anaplastic thyroid carcinoma exhibiting exclusively a spindle cell morphology. A case report and review of literature

Anaplastic thyroid carcinoma is a highly aggressive cancer accounting for 1-2% of thyroid malignancies. Cutaneous metastases from anaplastic thyroid carcinoma are exceedingly rare. We report a 65-year-old woman with anaplastic thyroid carcinoma (BRAF V600E mutation) who had lymph node metastases (pT4 N1b) treated by total thyroidectomy, postoperative radiotherapy, adjuvant chemotherapy (paclitaxel and pazopanib) and targeted therapy (vemurafenib). Nine months after initial diagnosis, radiographic studies revealed multiple pulmonary metastases. A dermatologic examination showed a solitary 1.2-cm chest nodule. Skin biopsy from this nodule revealed infiltrative dermal spindle cells arranged in poorly formed fascicles. Immunohistochemical studies demonstrated the tumor cells to be PAX-8 (+), pancytokeratin (+, focally), TTF-1 (-) and SOX-10 (-). Comparison with the patient's primary anaplastic thyroid carcinoma revealed focal areas of poorly differentiated spindle cells morphologically similar to the malignant spindle cells in the skin biopsy. Together, these findings confirmed the diagnosis of anaplastic thyroid carcinoma metastatic to skin. Cutaneous metastasis of anaplastic thyroid carcinoma composed exclusively of spindle cells broadens the histologic differential diagnosis of cutaneous spindle cell malignancies and presents further diagnostic challenges. PAX-8 may be useful in discerning the spindle cell component of anaplastic thyroid carcinoma from other spindle cell malignancies in the skin.

Malignant peripheral nerve sheath tumor: A rarity

Malignant peripheral nerve sheath tumor (MPNST) of the mandible is an uncommon tumor that develops either from a preexisting neurofibroma or de novo. MPNSTs are sarcomas that originate from peripheral nerves or from cells associated with the nerve sheath, such as Schwann cells, perineural cells or from fibroblasts. Because MPNSTs can arise from multiple cell types, the overall appearance can vary greatly from one case to the next. A case of MPNST of the right side of the mandible in a 23-year-old female is reported.

Patient-derived orthotopic xenograft (PDOX) nude mouse model of soft-tissue sarcoma more closely mimics the patient behavior in contrast to the subcutaneous ectopic model

AIM

Soft-tissue sarcomas are a group of rare mesenchymal carcinomas that include approximately 50 histological types, and account for 1% of all adult cancer cases. The yearly incidence of soft-tissue sarcomas in the USA is approximately 11,280 cases, with an overall mortality of 3,900 deaths per year.

MATERIALS AND METHODS

In this study, we established a patient-derived orthotopic xenograft (PDOX) from a patient with a soft-tissue sarcoma of the retroperitoneum in nude mice and compared it to a subcutaneous patient-derived model of the same tumor for histology.

RESULTS

In the PDOX model, a bulky tumor grew in the left retroperitoneum in the same manner as the patient's tumor. Upon histological examination, the majority of the PDOX tissue section comprised sarcomatous high-grade spindle cells of varying sizes, similar to the original patient tumor. In contrast, the majority of the subcutaneously-implanted tumor comprised round to oval cells.

CONCLUSION

These results indicate that the PDOX recapitulated the histology of the original tumor more than the subcutaneous model.

Recurrent solitary fibrous tumor in distal lower extremity: An extremely rare entity

Solitary fibrous tumor (SFT) represents a spectrum of mesenchymal tumors, encompassing tumors previously termed hemangiopericytoma, as having intermediate biological potential. Though they can occur at any site, lower distal extremity is a rare site and recurrence in it is extremely rare. Behavior of SFT is unpredictable. Histomorphology and clinical follow-up have poor correlation. The most important single indicator of clinical outcome is complete excision of the tumor at the time of primary presentation. Tumors with positive margins require close follow-up for several years owing to the potential for late local recurrence.

Desmin-positivity in spindle cells: under-recognized immunophenotype of lipoblastoma

Lipoblastoma is a distinct benign fatty tumor composed of adipocytes, lipoblasts, and primitive mesenchymal cells with a myxoid stroma. Lipoblastoma harbors characteristic fusion genes involving the PLAG1, resulting in aberrant expression of PLAG1. However, the nature of the primitive mesenchymal cells remains obscure. In our routine pathology practice, we noticed desmin-positive spindle mesenchymal cells in lipoblastomas, which is a hitherto poorly described phenomenon. Thus, we examined the expression of several myogenic markers including desmin in a variety of 95 mesenchymal tumors with fatty elements. Fourteen of the 15 lipoblastomas examined contained desmin-positive spindle cells, which also showed nuclear expression of PLAG1, whereas α-smooth muscle actin, muscle specific actin, h-caldesmon, and myogenin were negative. Some spindle cells in subsets of atypical lipomatous tumors/well differentiated liposarcomas (6/20), dedifferentiated liposarcomas (11/31) and pleomorphic liposarcomas (2/10) were positive for actins and/or desmin, supporting focal myofibroblastic or smooth muscle differentiation. The other tumors, including 11 myxoid/round cell liposarcomas, four spindle cell lipomas, and four lipofibromatoses, were negative for all of the myogenic markers assessed. The almost consistent desmin expression in spindle mesenchymal cells suggests a potential diagnostic utility of this marker and myofibroblastic phenotype of fractions in lipoblastoma cells.

Desmoplastic fibroma arising in the distal phalanx of the great toe: a case report

Desmoplastic fibroma (DF) of the bone is a rare locally aggressive tumor usually occurring in adolescents and young adults. These tumors most commonly occur in the mandibles and metaphyses of long bones but are extremely rare in small bones, often resulting in diagnostic problems. The occurrence of these tumors in the foot is especially limited. We report the clinical, radiographic, and histologic features of DF arising in the distal phalanx of the great toe and a review of the published data.

Infantile digital fibromatosis (inclusion body fibromatosis) observed in a baby without finger involvement

A 9-day-old male baby was hospitalized after his birth due to some swells under the skin. The hard consistency nodules observed under the skin all over the body of the patient were of different size, and presented lesions, among which the biggest was 1 × 1 cm. No lesions were observed on the fingers. By superficial ultrasonography, multiple isoechoic hypoechoic lesions were observed among the muscle plan. In thoracolumbar magnetic resonance imaging, multiple massif lesions retaining peripheral contrast (the biggest was 1.7 × 1.4 cm large) had been observed under the skin muscle plans, between the muscles of the extremities. The biopsy was positive for smooth muscle actin, but negative for desmin, S100, and CD34. These findings were diagnosed as infantile digital fibromatosis (IDF) (inclusion body fibromatosis). The case was presented with an objective to illustrate and remind that IDF can be observed in babies without finger involvement.

Nodular fasciitis of the oral cavity with partial spontaneous regression (nodular fasciitis)

Nodular fasciitis is a lesion found in the subcutaneous fascia that micoscopically presents as a benign proliferation of fibroblasts and myofibroblasts, which may be mistaken for a sarcoma due to clinically rapid growth. Diagnosis is by histopathology and of the immunohistochemical profile. We describe a case of nodular fasciitis in the oral cavity that demonstrated partial spontaneous regression. The patient was a 32-year-old man with a buccal mucosal mass, which had grown rapidly for 45 days. On microscopic examination, the lesion displayed a well-delineated but not encapsulated proliferation of spindle cells, with a nodular growth pattern. Immunohistochemical analysis showed positivity of the spindle cells for the antibodies against smooth muscle actin and muscle-specific actin (HHF-35). Treatment of such lesions typically involves complete conservative excision, but the lesion may regress eventually in the absence of definitive treatment.

A case of solitary fibrous tumor of the kidney

A solitary fibrous tumor (SFT) is an unusual spindle cell neoplasm that usually occurs in the pleura but has recently been described in diverse extrapleural sites. Urogenital localization is rare and to our knowledge, only 39 cases of SFT of the kidney have been described. Although SFT of the kidney is extremely rare, this tumor must be included in the differential diagnosis, whenever a renal tumor consisting of mesenchymal elements is encountered. We report a case of a large SFT of the right kidney which was clinically and radiologically thought to be renal cell carcinoma and a final diagnosis of SFT was made only after immunohistochemical study.

Solitary fibrous tumor of the kidney: a case report and review of the literature

A solitary fibrous tumor (SFT) is an unusual spindle cell neoplasm that usually occurs in the pleura but has recently been described in diverse extrapleural sites. Urogenital localization is rare, and only 19 cases of SFT of the kidney have been described. We report a case of a large SFT clinically thought to be renal cell carcinoma arising in the kidney of a 70-year-old man. The tumor was well circumscribed and composed of a mixture of spindle cells and dense collagenous bands, with areas of necrosis or cystic changes noted macroscopically and microscopically. Immunohistochemical studies revealed reactivity for CD34, CD99, and Bcl-2 protein, with no staining for keratin, S-100 protein, or muscle markers, confirming the diagnosis of SFT. This tumor is benign in up to 90% of cases. The immunohistochemical study is the key to diagnosis.