Unusual Site Research Articles

Malignant Lesion on Intraoperative Frozen Section with Histopathology Feature Alveolar Soft Part Sarcoma: A Case Report

Background: Alveolar soft part sarcoma (ASPS) are slow-growing inert soft tissue masses, but fast-growing masses are also reported. Because the cancer tissue is rich in blood vessels, distant metastasis is easy to occur through the blood tract, and lung metastasis is the most common. The diagnosis of ASPS should be combined with histopathology examination because of its rarity and often misdiagnosed, especially in unusual sites. Case presentation: A 22-year-old female came to the oncology surgery polyclinic at Dr. M. Djamil General Hospital Padang with a chief complaint of a lump in her left thigh since 1 year ago and has been getting enlarged in the last 6 months. The lump has been painful for the last 2 months. Upon an intraoperative frozen section examination, it was concluded that the lesion was malignant. Then, the tissue was prepared from formalin fixed paraffin embedded (FFPE), and the lesion was diagnosed as alveolar soft part sarcoma. Conclusion: In the case of ASPS, surgical management has an important role. The goal of the intraoperative frozen section of this patient is to determine whether the lesion is benign or malignant. There is a need for histological examination, collaboration, and optimal communication between pathologists and surgeons to avoid limitations and pitfalls examination.

SCHWANNOMA OF THE HEAD AND NECK REGION: A CASE SERIES IN A TERTIARY HEALTH CENTRE IN WESTERN ODISHA

Objective: Schwannoma is a benign peripheral nerve sheath tumour. Previously referred to as Neurilemmomas. It is a slow-growing tumour. The commonest site is the limb with a predilection to the upper limb. But, it has a 25–48% predilection for nerves of the head and neck. In the oral cavity, the commonest site is said to be the tongue. Methods: We report three cases of histopathologically diagnosed Schwannoma at unusual sites. The first case was a 52 y old lady with a palpable, firm, painless swelling in the occipital region of the scalp of size 2.0 x 1.0 x 1.0 cm. The second case was a 29 y old woman with a painless scalp swelling of 1 cm by 1 cm. The third case was a 23 y old boy who presented with a slow-growing and painless pedunculated swelling in the posterior pharyngeal wall for a year. All cases showed classical histopathologic pictures on microscopy. Results: All the patients were evaluated pre-operatively and subjected to an excisional biopsy. The post-operative period was uneventful and everything went according to plan for a full year. Conclusion: Schwannomas exhibit a slow growth rate, are present in all age groups, and are not specific to one gender. Extremities are the most common locations to occur, but some rare sites like the scalp, oral cavity, retroperitoneum, and internal viscera also exist. Magnetic resonance imaging (MRI) is helpful in those lesions, providing useful information about the location and nature of the lesion, eliminating differential diagnosis, and thus providing correct management plans.

Unusual Sites of Visceral Spread in Prostate Cancer: A Prostate-Specific Membrane Antigen-Based Theranostic Imaging Series.

Prostate cancer commonly metastasizes to lymphatic and skeletal systems with lesser frequency to visceral organs; however, uncommon visceral sites have also been found and reported as case reports. We present a series of uncommon metastatic visceral spread in prostate cancer on prostate-specific membrane antigen-based diagnostic and posttherapeutic imaging modalities.

Gastric-type adenocarcinoma of the uterine cervix: clinical features and future directions.

The concept of gastric-type mucinous carcinoma of the uterine cervix (GAS) has been accepted worldwide because of its aggressive clinical behaviour and the absence of high-risk human papilloma virus infection. The World Health Organization (WHO) 2020 classification divides cervical tumours into two categories: human papilloma virus-associated and human papilloma virus-independent. Hence, GAS is now classified as an human papilloma virus-independent gastric type. Because clinical studies have reported that GAS is refractory to conventional treatments such as chemotherapy and radiotherapy, especially at an advanced stage, and has aggressive features with widespread dissemination to unusual sites, such as the omentum, peritoneum and distant organs, it is urgent to establish new treatment strategies by comparing the molecular profiles of human papilloma virus-associated adenocarcinomas. A series of genetic mutations characteristic to GAS encourage the development of future treatment strategies such as targeted therapy and immunotherapy.

Immunohistochemical expression of H3.3 G34W in 100 giant cell tumors of bone and its diagnostic mimics, including its value in resolving uncommon diagnostic scenarios: A single institutional study at a tertiary cancer referral center, India.

There can be a diagnostic challenge in differentiating giant cell tumor of bone (GCTB) from its mimics. Lately, histone H 3 F 3 A (Histone 3.3 ) G34W has been identified as a promising immunohistochemical marker. This study was aimed at evaluating H3.3 G34W immunostaining in 100 GCTBs, including its value in resolving diagnostic dilemmas. Immunohistochemical staining for H3.3 G34W was graded in terms of staining intensity (1+ to 3+) and the percentage of tumor cells showing crisp nuclear staining. One hundred GCTBs occurred in 58 males and 42 females (M: F ratio = 1.3), of 7-66 years age (average = 31.3, median = 28), commonly in distal femur (26), followed by proximal tibia (17), distal radius (12), proximal humerus (7), metacarpals (7), sacrum (6), proximal fibula (6), and relatively unusual sites (19), including a single multicentric case. Out of 92 GCTBs, wherein H3.3 G34W immunostaining worked, 81 (88.1%) showed positive staining in the mononuclear cells, including tumors with fibrous histiocytoma-like areas, sparing osteoclast-like giant cells, with 3+ staining intensity in 65/81 (80%) tumors. All 7/7 (100%) malignant GCTBs showed positive staining, including the pleomorphic/sarcomatous cells. All 7/7 (100%) metastatic GCTBs showed positive immunostaining. Seven out of 10 post-denosumab treated GCTBs showed positive H3.3 G34W immunostaining in the residual mononuclear cells. None of the other 37 "giant cell-rich" lesions displayed H3.3 G34W immunostaining. Four of 9 GCTBs tested for H3.3 G34W mutation showed positive results. The diagnostic sensitivity and specificity of H3.3 G34W for GCTB were 88.1% and 100%, respectively. This constitutes one of the first reports from our country, further validating the diagnostic value of H3.3 G34W in differentiating GCTB, including metastatic and malignant forms from its mimics, including small biopsy samples. Its value in various diagnostic dilemmas is presented and utility in identifying residual tumor cells in post-denosumab treated GCTBs is worth exploring.

Solitary fibrous tumor occurring at unusual sites: A clinico-pathological series of 31 cases with emphasis on its wide morphological spectrum

Solitary fibrous tumor (SFT) is a relatively rare mesenchymal fibroblastic tumor occurring most commonly in adults with no gender predilection. Although the pathological diagnosis of SFT is usually straightforward, some difficulties may occasionally arise mainly due to the wide morphological spectrum exhibited by this tumor. In the present paper we aimed to evaluate the unusual clinicopathological features in a series of 31 SFTs arising from parenchymal organs, superficial soft tissues and deep soft tissues. Our results emphasize that SFTs may occur anywhere, including unusual sites such as periosteum of the thoracic spine, mesorectal tissue, hepatic hilum, paravescial space, kidney and breast. Moreover, a wide morphological spectrum was observed in tumors included in our series. The most striking morphological features observed included: extensive lipomatous component, myxoid stromal changes, epithelioid cell component, metaplastic mature bone, neurofibroma-like, myxofibrosarcoma-like and pseudoalveolar-like areas. Additionally, multinucleated giant cells and sarcomatous dedifferentiation were also identified.Our paper emphasizes that SFT may occur in unusual anatomical locations and exhibits a wide morphological spectrum. Pathologists must be aware of these features to avoid confusion with other benign and malignant neoplasms that may show overlapping morphological features.

Synovialosarcome primitif du rein : si tout était déjà dans les urines pyéliques ?

Synovialosarcoma is a malignant mesenchymal tumor of young adults that occurs in the deep soft tissues, particularly around large joints. When it occurs in more unusual sites, it could present a significant diagnostic challenge. In this case, a 19-year-old girl was treated for a pyloric mass. A pyelic urine cytology performed simultaneously with a pyloric biopsy proved to be a significant element of orientation and perfectly concordant with the histopathological aspect of the pyelic mass after nephrectomy. We report here the first case of renal synovialosarcoma documented in pyelic urine.

Vaccine-Induced Immune Thrombotic Thrombocytopenia: Clinicopathologic Features and New Perspectives on Anti-PF4 Antibody-Mediated Disorders.

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare yet severe adverse complication first identified during the global vaccination effort against SARS-CoV-2 infection, predominantly observed following administration of the ChAdOx1-S (Oxford-AstraZeneca) and Ad26.CoV2.S (Johnson & Johnson/Janssen) adenoviral vector-based vaccines. Unlike other anti-platelet factor 4 (PF4) antibody-mediated disorders, such as heparin-induced thrombocytopenia (HIT), VITT arises with the development of platelet-activating anti-PF4 antibodies 4-42 days post-vaccination, typically featuring thrombocytopenia and thrombosis at unusual sites. To explore the unique properties, pathogenic mechanisms, and long-term persistence of VITT antibodies in patients, in comparison with other anti-PF4 antibody-mediated disorders. This review highlights the complexity of VITT as it differs in antibody behavior and clinical presentation from other anti-PF4-mediated disorders, including the high incidence rate of cerebral venous sinus thrombosis (CVST) and the persistence of anti-PF4 antibodies, necessitating a re-evaluation of long-term patient care strategies. The nature of VITT antibodies and the underlying mechanisms triggering their production remain largely unknown. The rise in awareness and subsequent prompt recognition of VITT is paramount in reducing mortality. As vaccination campaigns continue, understanding the role of adenoviral vector-based vaccines in VITT antibody production is crucial, not only for its immediate clinical implications, but also for developing safer vaccines in the future.

Multisite Thrombosis in a Patient with Paroxysmal Nocturnal Hemoglobinuria

AbstractCase: Paroxysmal nocturnal hemoglobinuria (PNH) is an extremely rare bone marrow disorder caused by acquired mutations in the phosphatidylinositol glycan class A gene, which lead to a partial or total loss of the cellular complement regulators CD55 and CD59.1 In addition to complement-mediated hemolysis and cytopenia, venous and arterial thromboses at multiple and/or unusual sites are a common complication and occur in up to 44% of patients in historic PNH cohorts.1 2

Exploring the Molecular Aspects of Myeloproliferative Neoplasms Associated with Unusual Site Vein Thrombosis: Review of the Literature and Latest Insights.

Myeloproliferative neoplasms (MPNs) are the leading causes of unusual site thrombosis, affecting nearly 40% of individuals with conditions like Budd-Chiari syndrome or portal vein thrombosis. Diagnosing MPNs in these cases is challenging because common indicators, such as spleen enlargement and elevated blood cell counts, can be obscured by portal hypertension or bleeding issues. Recent advancements in diagnostic tools have enhanced the accuracy of MPN diagnosis and classification. While bone marrow biopsies remain significant diagnostic criteria, molecular markers now play a pivotal role in both diagnosis and prognosis assessment. Hence, it is essential to initiate the diagnostic process for splanchnic vein thrombosis with a JAK2 V617F mutation screening, but a comprehensive approach is necessary. A multidisciplinary strategy is vital to accurately determine the specific subtype of MPNs, recommend additional tests, and propose the most effective treatment plan. Establishing specialized care pathways for patients with splanchnic vein thrombosis and underlying MPNs is crucial to tailor management approaches that reduce the risk of hematological outcomes and hepatic complications.

An unusual foreign body nose: a case report

Nasal foreign bodies constitute an emergency and are more common in children with insertion generally via anterior nares. Case presentation: We present a case of 57-year-old-man with unusual entry site foreign body nose after external trauma to face, confirmed by 3D computed tomography and extracted through nasal route without any complication. Thus, nasal foreign bodies, a frequent accident in medical practice, usually harmless, but if neglected may cause complications hence prompt extraction is important.

Clinical characteristics and outcomes of patients with metastatic colitis-associated cancer treated with EGFR inhibitors.

37 Background: Colitis-associated cancer (CAC) is a devastating complication of inflammatory bowel disease. CAC tumor biology differs from that of sporadic colorectal cancer (CRC). Patients (pts) with (w/) metastatic CAC (mCAC) treated w/ 1st line (1L) chemotherapy have worse outcomes than pts w/ sporadic metastatic CRC (mCRC). EGFR inhibitor (EGFRi) w/ chemotherapy is standard of care for mCRC that is left (L) sided, RAS wild type (WT), without BRAF V600E mutation (mut) or ERBB2 amplification (amp). There are no published data on efficacy of EGFRi in CAC. We report outcomes of mCAC pts treated w/ EGFRi. Methods: Cases were identified by querying a prospectively maintained database of CAC pts seen at Memorial Sloan Kettering Cancer Center from 1/2000-present. Among mCAC pts who received EGFRi (n = 16), outcomes of interest: best response, progression-free survival (PFS), and overall survival (OS). PFS was calculated from date of 1st treatment w/ EGFRi until progression or death. OS was calculated from date of 1st treatment w/ EGFRi until death or last follow-up. Survival analyses were performed using Kaplan-Meier method. Data were obtained through review of electronic medical records. Results: 84 pts w/ mCAC were identified (52 L sided, 24 right [R] sided, 8 small bowel). Genomics were consistent w/ our prior reports: 79% TP53 mut, 19% APC mut, 14% MYC amp/gain, 32% KRAS mut, 4% BRAF mut, 6% ERBB2 amp. Limiting to pts w/ tumors that were L sided, RAS WT, without BRAF V600E mut or ERBB2 amp, we identified 34 (40%) mCAC pts. 16 (47%) of these pts received EGFRi as 2L or 3L therapy. 3 pts (19%) received EGFRi alone, 13 pts (81%) received EGFRi w/ FOLFIRI or irinotecan. 8 pts (50%) had tumors that were high grade and/or w/ signet ring features. Metastatic sites at initiation of EGFRi: lymph node (69%), liver (50%), lung (50%), peritoneum (38%), bone (38%), soft tissue (38%). 2 pts (12.5%, 95% CI: 1.5-38.3%) had a response, 4 pts (25%) had stable disease (SD), and 10 pts (62.5%) had progressive disease (PD) as best response. Median PFS and OS: 3.0 months (95% CI: 1.8-8.7) and 11.5 months (95% CI: 8.8-17.4), respectively. 2 additional pts w/ R sided CAC received EGFRi w/ SD and PD as best responses. Conclusions: Pts w/ mCAC, who by established criteria are eligible for treatment w/ EGFRi, have rapid progression and low response rates to EGFRi. This suggests that unlike sporadic CRC, CAC may not be driven primarily by EGFR. Many had high grade histology and unusual sites of metastases (bone, soft tissue). Experiments are under way to elucidate mechanisms underlying resistance to EGFRi and will be reported. These include immunohistochemistry for EGFR and its ligands, transcriptomic analyses to classify consensus molecular subtypes, and assessment of EGF dependence and EGFRi sensitivity in CAC organoids.

A rhodium-catalyzed C-H activation/cyclization approach toward the total syntheses of cassiarin C and 8-O-methylcassiarin A from a common intermediate.

Three short and efficient total syntheses of cassiarin C are reported, from a chromanone common key intermediate. A C-H activation strategy, under rhodium catalysis on its pivaloyl oxime, enabled the installation of the pyridine ring. Dehydrogenation of 8-O-methylcassiarin C afforded 8-O-methylcassiarin A. A kinetic experiment and DFT calculations of the intermediates helped to gain insight into the unusual site- and stereo-specific H/D exchange of cassiarin C in CD3OD.

Primary Hydatid Cysts in Rare Sites: A Series of Four Cases

Hydatid disease is caused by the larval stage of the tapeworm Echinococcus granulosus. The definitive hosts include dogs and canines. Humans are accidental hosts and do not play a role in the biological cycle of the worm. The mode of infection is through ingesting food contaminated with dog feces containing gravid proglottids and free eggs, which hatch in the intestine and form larvae. The larvae then penetrate the intestinal wall, enter the bloodstream, and typically settle in the liver followed by the lungs. However, in rare instances, hydatid cysts can occur in various unusual sites throughout the body and even in a disseminated manner, leading to atypical clinical presentations and diagnostic challenges. Hereby, authors report a series of four cases (three males and one female) of hydatid cysts occurring at unusual sites, mainly the brain, kidney, spleen, and lung. The common age group among the observed cases was the second to fourth decade, showing a male predominance. In cases of splenic and renal hydatid cysts, patients presented with intermittent dull aching pain over the left and right flanks, respectively. In both cases, ultrasonography revealed the presence of multiple cysts in the spleen and kidney. In the case of cerebral hydatid cysts, the patient provided a history of short-term memory loss along with a few non specific symptoms, and Magnetic Resonance Imaging (MRI) revealed a hyperintense cystic lesion. In pulmonary hydatid cysts, the patient presented with symptoms of cough, dyspnoea, chest pain, and expectoration. X-ray examination supported the presence of the cyst. Surgery, preferably radical cystectomy, is considered for treatment, and the diagnosis is always confirmed by histopathology.

Extra-Lymphatic Filariasis: A Study of Three Interesting Cases

Filariasis is a chronic disabling parasitic disease that causes a major public health problem in tropical countries like India. Wuchereria bancrofti is associated with almost 99.4% of cases. Filariasis not only affects the structure and function of lymphatic vessels but is also associated with extra-lymphatic pathology and diseases. Lymphatic filariasis is commonly found throughout the tropics and subtropics. While lymph nodes are the common sites, unusual sites include the breast, spleen, subcutaneous tissue, thyroid, bone marrow, urinary tract, sputum, bronchial washing, pleural and pericardial fluid. Patients from endemic areas presenting with swelling should be evaluated for filariasis. Here in present case series, the authors discussed three cases: filariasis of the breast with fibroadenoma, soft-tissue nodule, and splenic lesions, due to their extreme rarity and unusual sites. In the first case, 20 years old female patient presented with a lump in the left breast. The complete blood cell (CBC) revealed eosinophilia, but peripheral smears did not show the presence of microfilariae. On Fine Needle Aspiration Cytology (FNAC), smears showed Wuchereria bancrofti microfilaria in the background of fibroadenoma. The patient was treated with Diethylcarbamazine (DEC) for 21 days. Repeat CBC revealed a decrease in the absolute eosinophil count. Lumpectomy for fibroadenoma was performed, which showed fragments (dead) of the microfilarial parasite. The association of filariasis with fibroadenoma is possibly due to pre-existing subclinical filariasis when the neoplasm developed, as the patient hails from an endemic area. Filariasis presenting as a soft-tissue nodule is an uncommon incidence. In the second case discussed here, 30 years old female patient had soft-tissue swelling over the left elbow. Peripheral smear only revealed eosinophilia without any parasites. On FNAC, smears showed Wuchereria bancrofti microfilaria, along with lymphoid cells and a few eosinophils. The swelling subsided with DEC treatment, and repeat CBC showed a decrease in the absolute eosinophil count. The third case discussed here, involved an unknown 35 years old male, who was brought dead to the hospital. No clinical details were available. On autopsy, the spleen showed multiple white patches, ranging in size from 0.2 to 0.5 cm in diameter. All other organs were unremarkable. Microscopy showed many granulomas and numerous dead fragmented microfilariae. It was a case of isolated splenic filariasis, which is a rarely diagnosed entity. These unique cases will raise awareness of diagnosing and instituting proper therapy.

Management of HIT/anti-PF4 disorders

Heparin-induced thrombocytopenia (HIT) was widely known as a disease characterized by development of thrombosis with thrombocytopenia after heparin exposure. In addition, vaccine-induced immune thrombotic thrombocytopenia (VITT) has been described as a fatal disease involving simultaneous bleeding and thrombosis after COVID-19 adenovirus vector vaccination. These were caused by HIT antibodies and anti-PF4 antibodies, respectively, but both were autoantibodies that recognized PF4, and were found to have the same pathology with different severities. In recent years, many pathologies in which anti-PF4 antibodies are produced have been reported, and a new concept of anti-PF4 disorder has been proposed. Anti-PF4 disorders are often difficult to identify due to their diverse range of causes, and the prognosis varies greatly depending on whether anti-PF4 antibodies can be measured and early treatment performed after observation of thrombocytopenia of unknown cause or thrombosis at an unusual site. To avoid overlooking anti-PF4 disorders, clinicians should become familiar with the classification of these disorders and accurately select the necessary tests.

A Rare Tumor at an Unusual Site with a Rare Association.

A Rare Tumor at an Unusual Site with a Rare Association.

Case of Chondroma in Prepubic Space: A Rare Occurrence

The pelvic bone can be affected by a various diseases, including tumours. Cartilaginous tumours may develop in this area because it contains hyaline and fibrocartilage. The pelvis is known to host malignant tumours like chondrosarcoma. On the other hand, chondroma, a benign cartilaginous tumour, is occasional. Chondroma is known to occur in different osseous and extraosseous locations. Extraskeletal/soft-tissue chondroma, though rare, is known for its occurrence in various anatomical locations. Hereby, the authors present a case report of a chondroma in the prepubic space that manifested with urinary symptoms. A 58-year-old female, known to be diabetic, came with acute urinary retention. She experienced a recent onset of burning micturition and abdominal pain. Radiological and cytological findings were non diagnostic. During pelvic exploration, a solid mass of 3×3 cm was noted in the prepubic space without a connection to the urinary bladder or underlying bone. Excisional biopsy of the mass showed benign mature chondrocytes in a background of chondroid matrix, suggesting a benign cartilaginous tumour (chondroma). The patient is now free of her symptoms and is doing well during the follow-up at three months. Authors could not find any case reports of chondroma in the prepubic space in the literature. The present case of extraskeletal chondroma in the prepubic space is an infrequent entity at an unusual site.

Uncommon muscle metastatic sites of renal cell carcinoma

Introduction. Renal cell carcinoma (RCC) is the most common malignant renal tumor. It has a tendency for spreading to unusual and distant sites, such as the orbit, paranasal sinuses, thyroid gland, heart, skin, and muscles. Skeletal muscle metastases are accounting for only 0.4% of all metastatic localizations. Following CT, they may be presented in five different radiology types of lesions. The aim of our case was CT evaluation of rare skeletal muscle metastatic localizations of RCC, following the time interval of their occurrence in relation to the appearance of the primary tumor, with emphasis on metastases in the levator ani muscle, since this metastatic localization of RCC has not been recorded in the previous literature. Case outline. We present a 66-year-old man after partial nephrectomy, due to a primary diagnosis of RCC. Three years after the initial diagnosis, multiple distant metastases were verified at typical localizations, as well as rare localizations such as muscles, including levator ani. Conclusion. Advanced metastases in uncommon locations are most often accompanied by a poor prognosis, therefore the further algorithm includes monitoring the whole clinical and radiological status. Metastases in the levator ani muscle have been recorded for the first time in this report. Taking into account that this muscle has very important functions, such as supporting and raising the pelvic visceral structures, as well as having control of the flow of urine and defecation, it is of great importance to include this localization in the CT evaluation.

Primary Extranodal Lymphomas: A Case Series

Primary Extra-Nodal Lymphomas (pENLs) comprise a heterogeneous group of disorders. pENLs are mostly Non-Hodgkin Lymphomas (NHL), although infrequent case reports of extra-nodal Hodgkin lymphomas (HL) have emerged. The most common sites for pENLs are the Gastrointestinal Tract (GIT), Central Nervous System (CNS), and head and neck region. pENLs pose a significant diagnostic challenge due to their unusual locations, a variety of confounding symptoms, and limited data available regarding their progression. Here, we present a case series of five patients of pENL: splenic HL in a 10-year-old boy, splenic NHL in a 65-year-old woman, primary ovarian lymphoma, possibly Burkitt’s lymphoma, in a 22-year-old female, Primary CNS Lymphoma (PCNSL), likely Diffuse Large B-Cell Lymphoma (DLBCL), in a 67-year-old male, and a 53-year-old woman diagnosed with Primary Thyroid Lymphoma (PTL). These cases were all encountered in our tertiary care centre, and this series represents one of the first in our population. Thus, a population-specific understanding of pENLs will aid in better comprehending the disease in cases of unusual sites.