Rare Tumor Research Articles

Pneumonectomy for broncho-pulmonary carcinoids: a single centre analysis of surgical approaches and patient outcomes.

Pneumonectomy is a radical surgical procedure associated with significant morbidity and mortality. Its application in the context of pulmonary neuroendocrine tumours, including carcinoid tumours, requires meticulous preoperative planning and intraoperative precision. This study aims to assess the safety and efficacy of pneumonectomy in the management of these rare and challenging neoplasms. A retrospective analysis of patients who underwent pneumonectomy for pulmonary carcinoid tumours at our institution over a specified period was conducted. Data regarding patient demographics, tumour characteristics, surgical techniques, intraoperative complications, perioperative management, and long-term outcomes were collected and analysed. Between March 2001 and October 2022, 21 patients (7 male, 14 female) with carcinoid tumours underwent pneumonectomy on a total of 459 surgical operations for carcinoid. Preoperative bronchoscopic procedures were conducted in 90.4% of cases, leading to histological diagnoses for most. The median hospital stay was eight days, with no reported perioperative deaths. Median follow-up after surgery was 73 months, with a five-year overall survival of 65.4 months. Recurrences occurred in 28.6% of cases, primarily in atypical carcinoids. Despite the rarity of bronchial carcinoids, pneumonectomy is effective for low-grade malignancies, demonstrating positive short-and long-term outcomes. Radical lymph node dissection is fundamental in pathological staging and overall survival.

EBV-positive small cell neuroendocrine carcinoma of nasopharynx as a probably unique subtype of neuroendocrine carcinoma: a clinicopathologic study of three cases and literature review

BackgroundThere is currently scarcity of information on small cell neuroendocrine carcinoma of the nasopharynx (SCNEC-nasopharynx). It is believed that this type of cancer is not associated with Epstein-Barr virus (EBV) infection and is indistinguishable from classic SCNEC occurring in other organs.Materials and methodsHerein we provided 3 cases of nasopharyngeal mass in our hospital, two males and one female. On admission, these patients were considered nasopharyngeal carcinoma with lymph node metastasis, and one of them had liver metastasis. The nasopharyngeal mucosal tissues were biopsied for pathological examination including immunohistochemistry and in situ hybridization. PubMed database was searched for articles about SCNEC-nasopharynx published up to April 2024 in any language.ResultThe 3 cases had similar histological features of SCNEC in other organs but differed in rich- tumor-infiltrating lymphocytes (TILs). All of them stained for pancytokeratin (panCK) and epidermal growth factor receptor (EGFR). Case 1 and Case 2 diffusely expressed insulinoma-associated protein 1(INSM-1) and synaptophysin (Syn), Case 3 strongly stained for CD56 and Syn. Immunostaining of all 3 cases for p40, p63, TTF-1, CK20, S-100 and NUT showed negative. BRG-1, INI-1 and Rb were retained. And p53 all showed wild-type expression. The Ki-67 labeling indiced of case 1, 2, and 3 were 80%, 90%, and 80%, respectively. In situ hybridization showed strong and uniform nuclear positivity of EBV-encoded small RNAs (EBER) in the neoplastic cells of 3 cases.ConclusionEBV-positive SCNEC-nasopharynx was exactly rare. The origin of this tumor is still controversial. It may originate from EBV-infected mucosal epithelium like nasopharyngeal carcinoma. Based on our cases and relevant literature, we found EBV-positive SCNEC-nasopharynx as a probably site-specific subtype of SCNEC with differing pathogenetic mechanism. The subtype not only virus positivity but also that it was associated with TILs and did not show p53 or Rb alterations by immunohistochemistry. It may be more responsive to treatment and have a better prognosis than classic SCNEC. We will continue to follow-up these patients and collect additional cases to further understand the unique biology of this rare solid tumor.

Hepatic Epithelioid Hemangioendothelioma: A Case Report of an Extremely Rare Tumor

Epithelioid hemangioendothelioma is a very rare vascular tumour, with fewer than 500 cases described worldwide. Diagnosis is often multifocal or at an advanced stage with non-specific symptoms. Pathological examination by biopsy is crucial to confirm the diagnosis. The liver is the most frequent site of predilection, followed by the lungs and bones. The etiology of hepatic epithelioid hemangioendothelioma is poorly understood and is not linked to chronic liver disease, with a heterogeneous and unpredictable course depending on the individual. Given the rarity of this cancer, there are no established treatment standards for this type of tumor of intermediate malignancy. Surgical resection is performed in the case of unifocal disease, and orthotopic liver transplantation remains an option in the case of multifocal and/or unresectable disease, with high survival rates and disease free survival (DFS). Transcatheter arterial chemoembolization (TACE) and chemotherapy/radiotherapy regimens are other treatment possibilities. However, surveillance may be proposed for asymptomatic patients with a slow progression. We report the case of a patient followed for a multifocal EHE with pulmonary metastases, discovered following pain in the right hypochondrium. Morphological and immunohistochemical examination confirmed the diagnosis of hepatic epithelioid hemangioendothelioma. Given the moderate symptoms, surveillance was recommended for our patient with a good clinical course and radiological stability for 3 years.

Regression of cardiac angiosarcoma in a 17-year-old: a percutaneous biopsy effect

BackgroundCardiac angiosarcoma is a very rare and aggressive primary cardiac tumor associated with poor prognosis. Diagnosis is often delayed due to non-specific symptoms, with most cases involving metastases at the time of diagnosis. We describe a unique case of apparent tumor regression of cardiac angiosarcoma post percutaneous biopsy.Case PresentationA young male was admitted with suspected pericarditis. Echocardiogram revealed a pericardial mass. Cardiovascular magnetic resonance (CMR) suggested primary cardiac malignancy. Percutaneous biopsy was inconclusive, with subsequent CMR demonstrating apparent tumor regression. Interval imaging revealed further tumor growth, and surgical biopsy revealed primary cardiac angiosarcoma (PCAS). Causes of tumor regression following percutaneous biopsy are discussed.ConclusionsCases of suspected primary cardiac malignancy require careful follow up with serial multimodality imaging. Percutaneous biopsy effects should be considered in cases of tumor regression, and serial imaging should be planned afterwards.

Revisiting Pulmonary Sclerosing Pneumocytoma.

Pulmonary sclerosing pneumocytoma (PSP) is a quite rare tumor outside Eastern countries. This rarity, together with a wide histological appearance, makes its correct identification a diagnostic challenge for pathologists under the microscope. Historically, PSP was considered a vascular-derived neoplasm (sclerosing hemangioma), but its immunohistochemical profile clearly supports its epithelial origin. No specific molecular fingerprint has been detected so far. This short narrative revisits the clinical, histological, immunohistochemical, and molecular aspects of this tumor, paying special attention to some controversial points still not well clarified, i.e., clinical aggressiveness and metastatic spread, multifocality, the supposed development of sarcomatoid change in a subset of cases, and tumor associations with lung adenocarcinoma and/or well-differentiated neuroendocrine hyperplasia/tumors. The specific diagnostic difficulties on fine-needle aspiration cytology/biopsy and perioperative frozen sections are also highlighted. Finally, a teaching case of tumor concurrence of lung adenocarcinoma, neuroendocrine lesions, and PSP, paradigmatic of tumor association in this context, is also presented.

Neuroendocrine Lesions Arising From Mediastinal Teratoma-A Case Report and Literature Review.

Background. Neuroendocrine lesions arising from mediastinal teratomas are rare tumors with only small number of patients reported in literature. The behavior of these lesions appears to be different from traditional neuroendocrine neoplasms. A comprehensive review will be valuable for histologic assessment and treatment planning for similar cases. Case presentation. We present an example of a 57-year-old man who presented with cough. Subsequent work-up revealed an anterior mediastinal mass of 2.1 cm on computed tomography. The patient underwent robot-assisted thoracoscopic thymectomy. Histological examination revealed a mature cystic teratoma with a neuroendocrine component consisting of clusters of tumor cells with round to oval nuclei and a "salt-and-pepper" chromatin pattern. The tumor cells were immunoreactive to cytokeratin, synaptophysin, chromogranin, and INSM1, with a Ki-67 proliferative index of 4%. A histological diagnosis was mature teratoma with well-differentiated low-grade neuroendocrine tumor (carcinoid) was made. The patient was well and without disease after complete surgical excision at 10 months. Literature review. Literature reviewed yielded 13 examples of neuroendocrine lesions arising from mediastinal teratomas. No disease-related mortality was reported, even in lesions with high-grade neuroendocrine, carcinomatous, or immature teratomatous components. Conclusions. Surgical removal is the mainstay of treatment of these lesions, and the presence of a neuroendocrine component does not appear to negatively affect prognosis.

Rare tumors II: Adrenocortical tumors, neuroendocrine tumors of the appendix, pheochromocytoma and paraganglioma, pancreatoblastoma and solid pseudopapillary tumors of the pancreas.

Very rare tumors are usually divided into two groups: One includes tumors that are rare among both children and adults; the other one encompasses tumors that frequently occur in adults but are rarely observed in children. In this review, we focus on adrenocortical tumors, neuroendocrine tumors of the appendix, pheochromocytoma and paraganglioma, pancreatoblastoma and solid pseudopapillary tumors of the pancreas, with special attention to the role of surgery as main curative intervention or as part of the multimodal treatment.

Squamous Cell Carcinoma Arising in YAP1::MAML2 Fusion-Associated Metaplastic Thymoma: A Case Report.

Metaplastic thymoma is a rare thymic neoplasm that has generally been considered to follow a benign to indolent clinical course; however, 3 metaplastic thymomas with high-grade malignant transformation to sarcomatoid carcinoma have been reported. In recent years, both conventional metaplastic thymomas and this subset showing malignant transformation have been associated with recurrent YAP1::MAML2 fusions. We report a metaplastic thymoma showing transformation to squamous cell carcinoma, that to our knowledge is the fourth reported in the literature with transition to overtly malignant features and the first showing pure carcinomatous transformation, and in which YAP1::MAML2 fusion was demonstrated via next generation sequencing.

Collection of Rare Peripheral Nerve Tumors-Insights from the German Registry.

The most common peripheral nerve tumors are of a benign nature and include schwannoma or neurofibroma. In rare cases, other tumors or non-tumorous lesions can mimic peripheral nerve tumors clinically or radiologically. Based on data from the multicentric German Peripheral Nerve Tumor Registry (PNTR), which encompasses current information on 315 surgically treated patients from three high-volume centers, we present 61 cases of rare tumors and lesions that mimic tumors associated with peripheral nerves. This cohort displays considerable heterogeneity, featuring a broad spectrum of morphological features and biological potentials. Histopathological diagnoses include various intrinsic peripheral nerve tumors such as malignant peripheral nerve tumors (MPNSTs) (n = 13), perineurioma (n = 17), and hybrid nerve sheath tumors (HPNSTs, comprising schwannoma/perineurioma and schwannoma/neurofibroma) (n = 14), as well as atypical neurofibromatous neoplasm with unknown biological potential (ANNUBP) (n = 1). Additionally, the cohort encompasses extrinsic tumorous lesions like lymphoma (n = 3), lymphangioma (n = 2), hemangioma (n = 2), solitary fibrous tumor (n = 2), metastatic disease (n = 1), and single cases of other rare tumor entities (n = 6). An overview of the underlying pathology, imaging features, and clinical presentation is provided, with a brief description of each entity. A definitive preoperative differentiation between benign peripheral nerve tumors and rare intrinsic and extrinsic tumors is often not possible. Clinical examination and subtle imaging clues can at least indicate the possibility of a rare entity. The basic requirement is close cooperation between radiologists, neurologists, neuropathologists, and neurosurgeons at a specialized center to develop a multidisciplinary concept and offer the patient the best therapeutic approaches.

MRI features of combined hepatocellular-cholangiocarcinoma.

Combined hepatocellular cholangiocarcinoma (cHCC-CCA) is a rare liver tumor which has a more aggressive behavior and worse survival outcome than hepatocellular carcinoma (HCC), with a prognosis similar to that of intrahepatic cholangiocarcinoma (iCCA). With limited literature on the appearance of this tumor on MRI, it remains a diagnostic challenge. In this review, we looked at the currently described MRI findings in this uncommon entity. Based on studies conducted to date, a mixed pattern at imaging has demonstrated the highest specificity, seen as a combination of areas showing progressive enhancement of the lesion, arterial enhancement with washout, and areas of arterial enhancement without washout and/or hypovascularity. Tumor markers may aid in identification, particularly in cases where the imaging appearance mimics that of isolated HCC or iCCA. Intratumoral heterogeneity leads to difficulties with pathologic diagnosis from sampling due to the possibility of an incorrect diagnosis if the biopsy specimen does not contain adequate tissue comprising both histologic components.

A case report of primary Kaposiform hemangioendothelioma of the humerus.

To examine the clinicopathological and immunohistochemical features of Kaposiform hemangioendothelioma (KHE) and discuss its differential diagnosis and prognosis. A patient with KHE was examined; the patient's clinical and histopathological features were observed, and the expression levels of CD31, CD34, ERG, D2-40, SMA, GLUT-1, and LANA-1 were assessed. The patient was a four-year-old child with primary KHE of the humerus. She was admitted to the hospital because of pain in the right elbow joint and limited movement for more than 2years. Imaging revealed Langerhans cell histiocytosis. The child was not diagnosed with Kasabach-Merritt phenomenon (KMP). The tumor consists of multiple hemangiomatous nodules with infiltrative growth separated by fibrous connective tissue. The proliferating hemangiomatoid nodules consisted of crisscrossing short spindle-shaped cell bundles and erythrocyte-containing lacunar or crescentic vessels. Immunohistochemical staining showed that the tumor cells diffusely expressed CD31, CD34, ERG, and other vascular endothelium-derived markers; further, the tumor cells expressed neither GLUT-1 nor LANA-1. The patient's general condition improved after surgical resection. There was no tumor recurrence after more than 8months of follow-up. Primary KHE of the humerus is a rare vasculogenic tumor. It presents with morphological features that require an accurate differential diagnosis.

Sclerosing Perineurioma of the Orbit.

A 7-week-old boy presented to pediatric ophthalmology with a mass inferior to the medial canthus of the OS that was first noticed on day 3 of life. Crigler massages, warm compresses, and moxifloxacin HCl drops were administered without resolution of symptoms. Probing and irrigation for a presumed dacryocystocele were performed, but the nasolacrimal system was patent, and the mass persisted after the procedure. Oculoplastics was consulted for further evaluation and management. On exam, the tear lake was normal, there was no discharge to palpation of either lacrimal sac, and there was no erythema. An MRI was obtained that showed a mass with nonspecific features abutting the lacrimal sac. A gross total resection of the mass was performed, and it was sent for histopathologic evaluation. Pathology results yielded a diagnosis of sclerosing perineurioma, a rare soft tissue tumor previously unreported in the orbit.

Multiregion exome sequencing indicates a monoclonal origin of esophageal spindle-cell squamous cell carcinoma.

Esophageal spindle-cell squamous cell carcinoma (ESS) is a rare biphasic neoplasm composed of a carcinomatous component (CaC) and a sarcomatous component (SaC). However, the genomic origin and gene signature of ESS remain unclear. Using whole-exome sequencing of laser-capture microdissection (LCM) tumor samples, we determined that CaC and SaC showed high mutational commonality, with the same top high-frequency mutant genes, mutation signatures, and tumor mutation burden; paired samples shared a median of 25.5% mutation sites. Focal gains were found on chromosomes 3q29, 5p15.33, and 11q13.3. Altered genes were mainly enriched in the RTK-RAS signaling pathway. Phylogenetic trees showed a monoclonal origin of ESS. The most frequently mutated oncogene in the trunk was TP53, followed by NFE2L2, KMT2D, and MUC16. Prognostic associations were found for CDC27, LRP2, APC, and SNAPC4. Our data highlight the monoclonal origin of ESS with TP53 as a potent driver oncogene, suggesting new targeted therapies and immunotherapies as treatment options. © 2024 The Pathological Society of Great Britain and Ireland.

Sinonasal Leiomyoma: A Case Report and a Review of the Literature

Abstract Sinonasal leiomyoma is an exceptionally rare neoplasm arising from smooth muscle cells within the sinonasal tract. This abstract presents a case study of a 43-year-old male patient diagnosed with sinonasal leiomyoma, a distinctive and challenging entity in otolaryngology. The patient presented with a complex clinical history, including a 2-year interval between initial evaluation and definitive diagnosis. Initial histology suggested a smooth muscle tumour of uncertain malignant potential, highlighting the diagnostic intricacies associated with this condition. The radiological assessment revealed an extensive soft tissue mass with the involvement of multiple adjacent structures. The patient subsequently underwent surgical resection, leading to a revised histological diagnosis of leiomyoma. This case underscores the diagnostic challenges associated with sinonasal leiomyoma, emphasising the importance of comprehensive evaluation, including clinical history, radiological imaging, and histopathological examination. Long-term follow-up is essential for monitoring potential recurrences and optimising patient outcomes. By presenting this rare case, we aim to contribute to the limited body of literature on sinonasal leiomyoma and highlight the complexities surrounding its diagnosis and management in clinical practice.

Myxoid liposarcoma diagnosed on fine needle aspiration cytology: There is more to it than meets the eye.

Liposarcoma is a rare mesenchymal neoplasm commonly involving deep soft tissues and the retroperitoneum. Among the various types of liposarcoma, myxoid liposarcoma is the most frequently encountered in adolescents and young adults, with a predilection for lower extremities. Fine needle aspiration allows easy assessment and rapid on-site evaluation for distinguishing benign from malignant lipomatous lesions. Here, we present a case of myxoid liposarcoma in the calf region of a 19-year-old boy, diagnosed via fine needle aspiration cytology, and subsequently confirmed by histopathological examination after surgical resection. The intention behind this case report is to highlight the cytological features of myxoid liposarcoma and to improve understanding of this tumor entity, aiming to prevent misdiagnosis by inexperienced pathologists when evaluating cytology specimens.

Dual-Tracer Positron Emission Tomography/Computed Tomography with [18F]FDG and [18F]fluorocholine in a Patient with Metastatic Parathyroid Carcinoma.

Here, we describe the case of a 43-year-old male patient with a metastatic parathyroid carcinoma who underwent dual-tracer whole-body positron emission tomography/computed tomography (PET/CT) with [18F]fluorocholine and fluorodeoxyglucose ([18F]FDG) for staging. [18F]FDG PET/CT detected multiple cervical and mediastinal lymph nodal lesions with increased tracer uptake, whereas [18F]fluorocholine PET/CT detected increased tracer uptake on cervical and mediastinal lymph nodal lesions and bone and lung lesions with a better evaluation of metastatic spread. Due to these imaging findings, the patient underwent systemic treatment with chemotherapy. This case demonstrates the added value of dual-tracer PET/CT in this rare metastatic tumor.

The Fatty Dilemma: A Rare Instance of Extra- and Intravascular Lipoma of the Brachiocephalic Vein

AbstractOftentimes, incidental findings are made on routine diagnostic imaging. An intra- and extravascular lipoma is one example of an important incidental finding. Intravascular lipomas are rare benign vascular tumors that are typically asymptomatic. They are most commonly found in the inferior vena cava but have also been recorded in the superior vena cava, brachiocephalic vein, subclavian vein, internal jugular vein, external jugular vein, and common femoral vein. Here, we presented the case of a 64-year-old female patient with an incidentally discovered intra- and extravascular lipoma affecting the right subclavian and brachiocephalic veins. While benign, intravascular lipoma on imaging can resemble a malignant tumor such as leiomyosarcoma or thrombus. As a result, appropriate identification and classification of this imaging finding is crucial for avoiding an exorbitant and futile workup.

Succinate dehydrogenase A deficient renal cell carcinoma: A rare renal tumor distinct from typical Succinate dehydrogenase deficient renal cell carcinoma

Succinate dehydrogenase (SDH)-deficient renal cell carcinoma (RCC) is a rare subtype of RCC classified as a molecularly defined RCC in the fifth edition of the WHO. Most gene alterations in patients with SDH-deficient RCC involve the SDHB subunit, with less involvement of the SDHC, SDHA, and SDHD subunits. Four cases of SDHA-deficient RCC have been reported in the literature, of which one case was associated with an NF2 gene mutation. Herein, we report six novel SDHA-deficient RCC cases, including two cases with NF2 gene mutations. In contrast to the typical morphology of SDH-deficient RCC, the six tumors mainly displayed glandular, sheet-like, or papillary growth patterns with prominent nucleoli (Grades 2–3), among which two cases with NF2 mutations had prominent nucleoli (Grade 3), large transparent vacuoles in the cytoplasm, and a large number of lymphocytes in the stroma. Six tumors showed negative immunohistochemical staining for SDHA and SDHB, and three cases presented with high expression of PD-L1. Second-generation sequencing revealed novel pathogenic somatic SDHA gene mutation and NF2 gene mutations in six and two tumors, respectively. Follow-up data were collected for the six patients with a follow-up time ranging from 7 to 268 months, and all six patients have survived to date. One patient received targeted therapy for tumor metastasis to the lungs after seven months, and another patient with an NF2 gene mutation received immunotherapy for lymph node metastasis revealed during surgery. SDHA-deficient RCCs with NF2 gene mutations have the ability to metastasize but might respond well to immunotherapy. For the first time, we report the largest number of SDHA-deficient RCC cases and comprehensively investigate their clinicopathological and molecular features to provide important guidance for diagnosis and clinical immunotherapy.

Advances in molecular basis of response to immunotherapy for penile cancer: better screening of responders.

Penile cancer is a rare malignant tumor of the male urinary system. The treatment benefit of standard first-line chemotherapy is not ideal for patients with locally advanced or metastatic lymph nodes. Immunotherapy has brought new treatment strategies and opportunities for patients with penile cancer. At present, clinical studies on immunotherapy for penile cancer have been reported, and the results show that it is effective but not conclusive. With the development of immunotherapy and the progress of molecular research technology, we can better screen the immunotherapy response population and explore new combination treatment regimens to evaluate the best combination regimen and obtain the optimal treatment options, which is also an important research direction for the immunotherapy of penile cancer in the future.

Ultrasonography Findings in Ovarian Hemangiomas: Report of Three Cases and Review of the Literature.

Ovarian hemangioma is a rare ovarian tumor. The imaging manifestations were rarely mentioned in previous literatures.One of the patients came to hospital with the complaints of an elevation of CA125. Another two patients found a mass in adnexa area accidentally. The oophorectomy procedures were performed and the pathological results of ovarian hemangioma were concluded. We summarized the ultrasound features of three cases retrospectively, of which could provide more information before operation to guide a management direction.A well-defined, regular-shape solid mass in ovary could be considered the possibility of hemangioma, especially when a richly vascularized tumor with prominent blood flow is detected on color Doppler sonography.