Well-circumscribed Tumor Research Articles

Smooth Muscle and Adenoma-Like Renal Tumor (SMART)- A Rare Biphasic Renal Tumor with a Review.

Smooth muscle and adenoma-like renal tumor (SMART) is a biphasic tumor composed of cytologically bland stromal and epithelial components. It has many histopathological mimickers. A 57-year-old man presented with a left renal mass. The left radical nephrectomy showed a 13.5 cm tumor involving the entire kidney. The microscopic examination showed an unencapsulated, well-circumscribed biphasic tumor composed predominantly of intersecting bundles of smooth muscle, admixed with focal epithelial components arranged in cystic, tubular, tubulopapillary, nests, and cords. Both the components lacked nuclear atypia. Using immunohistochemistry, the spindle cells were positive for SMA and desmin, focally positive for CD10, and negative for ER, PR, and HMB45. The epithelial cells were positive for PAX8 and keratin 7 and negative for CD10. We report an additional example of SMART with a literature review. Knowledge about this recently described entity would lead to a better understanding of the clinicopathological features and histogenesis of this tumor.

Pudendal Schwannoma; A Rare Reason for Scrotal and Penile Pain

Schwannomas are benign nerve sheath tumors that usually arise from cranial and periferal nerves. Pelvic region schwannomas are rare tumors and only a few cases have been reported in literature. Pudendal nerve schwannomas usually present as a cause of ipsilateral scrotal, penile and perineal region pain. We report the case of a 66-year-old man referred for worsening pain of 6 years duration involving the right scrotal and right penile shaft. After a series of repeated scrotal and penile ultrasonographies (USG), lumbar and brain magnetic resonance (MR) imaging and also blood tests, MR imaging of the pelvic region detected a well-circumscribed small pelvic wall tumor on the pathway of pudendal nerve. Based on the location, imaging characteristics and comparing to the cases reported in literature, we considered this tumor as a pudendal schwannoma. The most commonly described surgical approach for pelvic schwannomas has been open median laparotomy with transperitoneal dissection. The patient refused surgery, for this reason for treatment and control of the pain he underwent nerve block at anesthesiology clinic. At the 4-week follow-up, the patient described a significant decrease in pain.

Giant Bilateral Adrenal Leiomyoma Case Report

Introduction: Adrenal leiomyoma is extremely rare and is thought to arise from the smooth muscle wall of the central adrenal vein and its branches; Clinically they may present as abdominal pain or flank pain. These tumors generally have a low biological potential. The surgical indication for adrenal tumors is based mainly on functionality and the risk of malignancy. Clinical Case: 39-year-old male, with no significant history. Who comes to the general surgery outpatient clinic due to the presence of progressive abdominal distension and long-term abdominal pain. An abdominopelvic CT scan was performed, which revealed bilateral, well-circumscribed tumor with heterogeneous characteristics located in the left and right adrenal area, negative functional tests. An exploratory laparotomy was performed, revealing two giant adrenal tumors, definitive study reporting bilateral adrenal leiomyoma. Conclusion: We present a rare case of bilateral primary adrenal leiomyoma of which no similar case was found in the reviewed literature. These tumors are very difficult to diagnose preoperatively. as they are often not counted in adrenal samples and clinical suspicion is very low. As a result, they are diagnosed postoperatively after pathological examination of the surgical specimen. At the moment, early and complete surgical resection is the main treatment.

Osteoblastoma Recurring as High-grade Osteosarcoma

Abstract Introduction/Objective Osteoblastoma is a benign, bone-forming neoplasm that presents as a well-circumscribed lesion amenable to excision. The prognosis is good despite a 20% recurrence risk. Malignant transformation is very rare. Osteoblastoma-like osteosarcoma is a rare form of osteosarcoma that shares similar clinical, radiographic, and pathological characteristics Methods/Case Report A 24-year-old female presented with a large palpable mass in the posterior occiput. The lesion progressively enlarged over 2 years, finally becoming symptomatic. Magnetic resonance imaging demonstrated an extradural posterior fossa expansile skull mass measuring 6.0 x 5.7 x 4.7 cm that showed multiple fluid/fluid levels. The mass was resected. Pathology demonstrated a well-circumscribed neoplasm that was cellular and composed of large polyhedral osteoblasts with eccentric oval nuclei and abundant amphophilic cytoplasm. Tumor cells were intimately associated with numerous small interconnecting, irregular bony trabeculae. Scattered mitotic figures of normal configuration were noted. The findings were compatible with an epithelioid osteoblastoma with prominent secondary aneurysmal bone cyst-like changes. The patient was lost to follow-up but presented 3 years later with severe migraines. Imaging demonstrated a large heterogeneous enhancing mass centered about the occipital cranioplasty with both intracranial and extracranial components. Reexcision was performed. Sections showed a well- circumscribed tumor, delineated by a rim of subperiosteal reactive bone, with an epithelioid morphology. However, it also demonstrated areas of necrosis, extensive sheet-like growth, conspicuous mitoses, and cytological atypia not seen in the previous specimen. Therefore, diagnosis of osteoblastoma-like osteosarcoma was rendered after expert consultation. Results (if a Case Study enter NA) NA Conclusion This case highlights the exceedingly rare evolving nature of osteoblastomas and their high-grade transformation potential.

Rare Hybrid Perineurioma and Granular Cell Tumor: A Pediatric Case.

We present a case of a 13-year-old patient with a distinct tumor with both granular cell and perineurial elements, located on the lower lip. The patient presented with a long-standing lip mass that was clinically felt to most likely represent a mucocele. Following surgical excision, histopathological examination revealed a well-circumscribed tumor composed of granular cells with positive S100 protein staining and spindled cells positive for EMA and GLUT-1, confirming mixed neuroectodermal and perineurial origin. This is the first case documenting a perineurial-granular cell hybrid tumor in a patient under 18 years old, and the first to be reported in the head and neck. This case expands our understanding of hybrid PNSTs, emphasizing the importance of considering diverse clinical presentations, especially in the context of rare pediatric occurrences in atypical locations.

CNS tumors with PLAGL1-fusion: beyond ZFTA and YAP1 in the genetic spectrum of supratentorial ependymomas

A novel methylation class, “neuroepithelial tumor, with PLAGL1 fusion” (NET-PLAGL1), has recently been described, based on epigenetic features, as a supratentorial pediatric brain tumor with recurrent histopathological features suggesting an ependymal differentiation. Because of the recent identification of this neoplastic entity, few histopathological, radiological and clinical data are available. Herein, we present a detailed series of nine cases of PLAGL1-fused supratentorial tumors, reclassified from a series of supratentorial ependymomas, non-ZFTA/non-YAP1 fusion-positive and subependymomas of the young. This study included extensive clinical, radiological, histopathological, ultrastructural, immunohistochemical, genetic and epigenetic (DNA methylation profiling) data for characterization. An important aim of this work was to evaluate the sensitivity and specificity of a novel fluorescent in situ hybridization (FISH) targeting the PLAGL1 gene. Using histopathology, immunohistochemistry and electron microscopy, we confirmed the ependymal differentiation of this new neoplastic entity. Indeed, the cases histopathologically presented as “mixed subependymomas-ependymomas” with well-circumscribed tumors exhibiting a diffuse immunoreactivity for GFAP, without expression of Olig2 or SOX10. Ultrastructurally, they also harbored features reminiscent of ependymal differentiation, such as cilia. Different gene partners were fused with PLAGL1: FOXO1, EWSR1 and for the first time MAML2. The PLAGL1 FISH presented a 100% sensitivity and specificity according to RNA sequencing and DNA methylation profiling results. This cohort of supratentorial PLAGL1-fused tumors highlights: 1/ the ependymal cell origin of this new neoplastic entity; 2/ benefit of looking for a PLAGL1 fusion in supratentorial cases of non-ZFTA/non-YAP1 ependymomas; and 3/ the usefulness of PLAGL1 FISH.

A Knee Pain Referred to a Dermatologist

A painful lesion on the skin can arise from any of the cutaneous structures. A 51-year-old man presented with left knee pain of 1-year duration that got aggravated by contact with clothing or light touch. His symptoms failed to improve despite multiple visits to orthopedics and neurologists. On examination, a 1 cm × 2 cm tender nodular lesion was present on the left knee with surface scaling. Dermoscopy showed peripheral scaling with a rich vascular network interlaced with structureless white areas. The lesion was excised, and histopathology showed fibrocollagenous tissue along with a well-circumscribed encapsulated tumor composed of islands and nests of monomorphic cells with round centrally placed nuclei, reported as a glomus tumor. Post excision, the patient was asymptomatic, and no recurrence was observed. Glomus tumors are classically described to arise from fingertips or extremities. Atypical sites can also be involved, with very few cases reported in the literature.

Papillary renal neoplasm with reverse polarity: an observational study of histology, immunophenotypes, and molecular variation.

Papillary renal neoplasm with reverse polarity (PRNRP) is a novel entity with unique clinicopathological characteristics, and only a small number of patients with PRNRP have been described. We retrospectively analyzed the data for nine patients with PRNRP and evaluated differences in the clinical, histomorphological, immunohistochemical, and molecular features; prognosis; and differential diagnosis of PRNRP from other renal tumors with papillary structure. There were six males and three females aged 36 to 74 years (mean: 62.33 years; median: 68 years). All the tumors were solitary and ranged from 1 to 3.7 cm (mean: 2.17 cm; median: 2 cm), with three and six tumors arose in the left and right renal tract, respectively. Pathologically, PRNRP is a small, well-circumscribed neoplasm with predominant papillary formations. The lining epithelium is composed of a monolayer of cuboidal to low-columnar cells with low-grade nuclei arranged against the apical pole of the tumor cells. Edema, mucinous degeneration, and hyaline degeneration are found in the fibrovascular cores. Foamy macrophages, psammoma bodies, hemosiderin deposition, and infiltrative tumor boundaries were present in some patients. Immunohistochemically, all tumors showed diffuse positive staining for GATA3. Sanger sequencing confirmed the presence of KRAS mutation in seven patients. All patients had a good prognosis after surgery and were relapse free. Positive staining for GATA3 and negative staining for vimentin were the most significant markers for differentiating PRNRP from other renal tumors with analogous structure. These findings suggested that PRNRP is a distinctive subtype of renal tumor with specific pathological features and indolent behaviors that should be distinguished from other renal tumors, especially papillary renal cell carcinoma. A monolayer of tumor cells with an inverted nuclear pattern, positive staining for GATA3, and KRAS mutation are essential for pathological diagnosis. Owing to its satisfactory prognosis, the surveillance and follow-up of patients with PRNRP should be additionally formulated.

Case report: Cystic vestibular schwannoma

Background: Cerebellopontine angle tumors are a severe condition because of their life-threatening and functional loss potential, explained by the narrowness of the posterior fossa. The vestibular schwannoma, or acoustic neuroma, is a benign, well-circumscribed extraaxial tumor that arises from Schwann cells of the vestibulocochlear cranial nerve. The tumor is usually mainly solid, but can sometimes develop small cystic areas, due to degenerative modifications, causing microcyst formation. The coalescent of small cysts leading to forming a larger one, and responsible of a predominant cystic contingent, is rare, which makes interesting the case we are about to present. Case report: We are about to report the case of a 64-year-old male patient, with no particular medical history, which clinical interview has noted only tinnitus as a present symptom. He had experienced one year ago several disequilibrium and dizziness episodes, who have subsequently stopped over time, without any particular treatment. He also felt a little loss of hearing, especially in the left ear, but thought it was probably age related. No clinical abnormality including the facial nerve palsy was found. The MRI showed a stage 4 (Koos classification) left cystic vestibular schwannoma. This lesion was compressing the left vertebral and basilar arteries, the brain stream, the left cerebellar hemisphere, the left middle cerebellar peduncle, and the fourth ventricle, causing a triventricular hydrocephalus. After reviewing all potential therapeutic options, the patient declined surgery and decided to postpone the treatment. Conclusion: MRI is definitely the best way to explore the posterior fossa, especially the cerebellopontine angle, and helps us differentiate between all numerous tumors than can develop in this space.

Radiologic Features of Well-circumscribed Orbital Tumors With Histopathologic Correlation: A Multi-center Study.

To delineate specific imaging characteristics of solitary fibrous tumors, schwannomas, cavernous venous malformations, and well-circumscribed orbital lymphoma. Patients undergoing excisional biopsy of solitary fibrous tumor, schwannomas, cavernous venous malformations, or well-circumscribed orbital lymphoma with preoperative MRIs available for review were identified at 3 academic centers in the United States and Australia. An exploratory statistical analysis was performed to identify important radiologic features, which were subsequently included in a random forest model. Histopathologic correlates were evaluated in representative cases. A total of 91 cases were included with a mean age of 52.9 ± 17.2 years. Nearly all solitary fibrous tumors were located in the anterior or mid orbit (87.5%) and they more commonly demonstrated intralesional heterogeneity on T2-weighted imaging (45.5%) ( p < 0.01). Compared with the other tumors, schwannomas tended to be intraconal (66.7%) and were often in the mid or posterior orbit (83.4%) ( p < 0.01). Cavernous venous malformations characteristically demonstrated progressive contrast enhancement (93.9%; p < 0.01). Most lesions in all 4 groups were hypointense on T1-weighted imaging (80%-100%; p = 0.14) and only well-circumscribed orbital lymphoma tended to also be hypointense on T2 (81.8%) ( p < 0.01). Finally, cases of lymphoma had significantly lower apparent diffusion coefficient ratios (0.9 ± 0.2) ( p < 0.001), while the other 3 groups were not significantly different from one another (cavernous venous malformations: 1.8 ± 0.4; schwannomas: 1.8 ± 0.5; and solitary fibrous tumor: 1.6 ± 0.6) ( p = 0.739). Key features that aid in the differentiation of these 4 tumors from one another include T2 intensity and homogeneity, early contrast-enhancement pattern, and ADC ratio.

Giant oral lipoma: a rare case report involving the masseter muscle

Lipoma is a benign neoplasm that primarily affects middle-aged individuals and is rare in the maxillomandibular region. Most lipomas are between 2 and 15 mm in diameter. Although rare, they can reach large dimensions and cause aesthetic and functional problems such as dysphonia, dysphagia, and facial asymmetry. We report a case of an extensive lipoma invading the masseter muscle region with a 2-year history in a 36-year-old man who underwent surgery under general anesthesia. A well-circumscribed neoplasm composed of mature adipocytes with a thin fibrous capsule was seen on histopathology analysis. The 6-month follow-up showed good healing without recurrence.

Unclassified Sex Cord/Gonadal Stromal Testis Tumour with a “Pure “Spindle Cell Component: Pathological Features And Review of The Literature

Background: About 2-5% of adult testicular tumors are classified as sex cord/stromal tumors, which are an uncommon group of tumors of the testis. Occasionally, a small percentage of Sex Cord/stromal Testis Tumors (SCST) that are primarily composed of spindle cells seem to be unclassifiable. There are about six cases reported where spindle cells predominate, four of which are consisting purely of spindle cells. At the morphologic level, a striking resemblance to a fibroma has raised the notion of a possible fibrothecoma, but this is not supported by the immunohistochemistry, and the features are consistent with an unclassified sex cord/stromal tumor with a “pure” spindle cell component. Description: A 45-year-old man with a firm mass in the lower pole of the left testis for 3 years. The patient had no comorbidities and no features of endocrinopathies. All blood tests were normal. The ultrasound showed a solitary hypoechoic mass with increased blood flow by Doppler scan. A well-circumscribed tumor measuring 30mmx 15mm with no discernible capsule was identified macroscopically. Microscopy showed a well-circumscribed spindle cell lesion with no necrosis, cytological atypia, or mitoses. The tumor cells appeared spindled with eosinophilic cytoplasm, vesicular nuclei, and occasional nucleoli. No nuclear grooves were noted in the tumour cells. No vascular invasion was present. Actin, calretinin, CD99, S100, and inhibin were positively immunoreactive. Conclusion: The findings were consistent with an Unclassified pure spindle SCST, a rare tumor with a benign course that must be distinguished from several spindle cell neoplasms. There are no biochemical markers for the diagnosis of this tumor, thus requiring meticulous clinical examination, especially if it is small in size. We report a case of “pure spindle cell sex cord stromal tumour of the testis in a 45 years old man in which the histomorphological as well as the immunohistochemical features are consistent with the diagnosis of unclassified sex cord/stromal testis tumor with “pure” spindle cell component.

Intrapulmonary schwannoma presenting as an asymptomatic lung mass: a case report

BackgroundSchwannomas are solitary well-circumscribed encapsulated benign tumors that exhibit Schwann cell differentiation, and arise directly from myelinated peripheral or central nerves. Although they are usually asymptomatic and found incidentally, schwannomas can cause symptoms due to compression of nearby structures which, depending on the location, can make clinical presentations widely variable. Despite their rarity, schwannomas have been documented in a number of locations including the limbs, cerebellopontine angle, posterior mediastinum, and, far more infrequently, the lungs.Case presentationIn this article, we report an incidental finding of an intrapulmonary schwannoma in a 59-year-old Pakistani woman who was grossly asymptomatic upon presentation to the cardiothoracic surgery clinic. An [18F]fluorodeoxyglucose positron emission tomography/computed tomography scan revealed a lobulated soft-tissue lesion measuring 23 mm × 23 mm in the lower lobe of the right lung. A computed tomography-guided core biopsy of the mass was performed, which revealed a benign spindle cell lesion based on histopathological examination and immunohistochemical staining. The mass was surgically resected via a right lower lobectomy, and subsequently confirmed to be an encapsulated neoplastic lesion composed of well-differentiated Schwann cells. There were no short- or long-term complications, morbidities, or recurrences based on 1-year follow-up.ConclusionThis report underscores the predominantly asymptomatic nature of schwannomas and reemphasizes the efficacy of surgical resection as a safe and curative procedure for a tumor of this nature. Albeit very rare, intrapulmonary schwannomas can be considered a differential diagnosis when encountering solitary asymptomatic pulmonary nodules or masses.

Laparoscopic Transperitoneal Adrenalectomy for Adrenal Tumors in Children: Technical Considerations and Surgical Experience.

Aims: This study aimed to review our surgical experience of laparoscopic adrenalectomy (LA) for adrenal masses in the pediatric age group. Materials and Methods: The electronic medical records of all patients younger than 18 years of age who underwent LA between 2016 and 2023 were retrospectively reviewed. Children with adrenal tumors localized to the site of origin without evidence of encasement of major vasculature or involvement of adjacent organs were considered for LA. Patients with diagnosis of malignant adrenal tumor on preoperative work-up underwent open adrenalectomy. Data were collected regarding demography, clinical presentation, hormonal workup, imaging, duration of surgery, transfusion requirement, conversion rate, postoperative recovery, duration of intravenous (i.v.) analgesia and hospital stay, pathology, complications, and status at follow-up. Results: Between 2016 and 2023, LA adrenalectomy was performed in 11 patients (6 boys and 5 girls) with a mean age of 46.3 (8-120) months. A functional tumor was detected in 6 (54.5%) children, manifesting clinically with Cushing's syndrome (3), virilization (1), feminization (1), or Conn's syndrome (1). Seven (63.6%) tumors originated from the right adrenal, and 4 (36.4%) from the left adrenal gland. The mean tumor weight and size was 49.1 (10-80) g and 5.6 (3-8) cm, respectively. Histopathology included adrenal adenoma (5), ganglioneuroma (3), ganglioneuroblastoma (1), myelolipoma (1), and intermediate adrenocortical tumor (1). The mean surgery duration was 186.6 (120-265) minutes. Intraoperative blood transfusion was required in 2 (18.2%) patients and none required conversion. Full feeds were resumed at 42.7 (24-60) hours, i.v. analgesia requirement was for 54.5 (36-72) hours and mean hospital stay was 5.1 (3-8) days. All patients were symptom-free with no recurrence at mean follow-up period of 50.6 (3-83) months. Conclusions: In children with well-circumscribed, localized, and noninvasive adrenal tumors, LA is feasible, effective, and safe with all advantages of minimally invasive surgery.

Surgical outcomes and risk factors for recurrence of myxopapillary ependymoma: a single-center experience.

Myxopapillary ependymomas (MPEs) are low-grade, well-circumscribed tumors that often involve the conus medullaris, cauda equina, or filum terminale. They account for up to 5% of all tumors of the spine and 13% of spinal ependymomas, with a peak incidence between 30 and 50 years of age. Because of the rarity of MPEs, their clinical course and optimal management strategy are not well defined, and long-term outcomes remain difficult to predict. The objective of this study was to review long-term clinical outcomes of spinal MPEs and identify factors that may predict tumor resectability and recurrence. Pathologically confirmed cases of MPE at the authors' institution were identified and medical records were reviewed. Demographics, clinical presentation, imaging characteristics, surgical technique, follow-up, and outcome data were noted. Two groups of patients-those who underwent gross-total resection (GTR) and those who underwent subtotal resection (STR)-were compared using the Mann-Whitney U-test for continuous and ordinal variables and the Fisher exact test for categorical variables. Differences were considered statistically significant at p ≤ 0.05. Twenty-eight patients were identified, with a median age of 43 years at the index surgery. The median postoperative follow-up duration was 107 months (range 5-372 months). All patients presented with pain. Other common presenting symptoms were weakness (25.0%), sphincter disturbance (21.4%), and numbness (14.3%). GTR was achieved in 19 patients (68%) and STR in 9 (32%). Preoperative weakness and involvement of the sacral spinal canal were more common in the STR group. Tumors were larger and spanned more spinal levels in the STR group compared with the GTR cohort. Postoperative modified McCormick Scale grades were significantly higher in the STR cohort compared with the GTR group (p = 0.00175). Seven of the 9 STR patients (77.8%) underwent reoperation for recurrence at a median of 32 months from the index operation, while no patients required reoperation after GTR, for an overall reoperation rate of 25%. Findings of this study emphasize the importance of tumor size and location-particularly involvement of the sacral canal-in determining resectability. Reoperation for recurrence was necessary in 78% of patients with subtotally resected tumors; none of the patients who underwent GTR required reoperation. Most patients had stable neurological status postoperatively.

Cytopathology of glioneuronal and neuronal tumours with histological correlations.

Glioneuronal and neuronal tumours constitute a diverse group of tumours that feature neuronal differentiation. In mixed glioneuronal tumours, a glial component is present in addition to the neuronal component. With a few exceptions (eg diffuse leptomeningeal glioneuronal tumour) they are well-circumscribed and slow-growing tumours, which is why their prognosis is intrinsically favourable after gross total resection. Rendering an intraoperative diagnosis of glioneuronal/neuronal tumour is therefore important-neurosurgeons should remove them to prevent the persistence of clinical symptoms and/or recurrence. In this context, cytopathological examination can be especially useful for assessing cellular details when frozen section artefacts render poor-quality preparations, as is the case for this group of tumours, which are frequently mistaken for infiltrating gliomas (eg diffuse astrocytoma infiltrating grey matter, oligodendroglioma) on frozen section slides. The aim of this article is to review the cytomorphological features of glioneuronal and neuronal tumours according to the 2021 World Health Organization classification of central nervous system tumours, 5th edition. Additionally, since interpretation in intraoperative cytology relies on intuiting tissue patterns from cytology preparations, representative histological figures of all discussed entities have been included. Clues for specific diagnoses and the primary diagnostic problems encountered during intraoperative procedures are also discussed.

A Rare Case of Hyoid Osteoma.

Solid primary tumors of the hyoid bone are extremely rare. Osteomas are benign, slow-growing, usually asymptomatic, and well-circumscribed tumors broadly attached to the bone surface composed of mature lamellar/cortical-type bone with unknown etiology. Osteomas commonly occur in bones formed by membranous ossification, almost exclusively occurring in the head and commonly involving the paranasal sinus, skull vault, mandible, and nasal bone. We discuss a rare case of osteoma involving the hyoid bone.

Solitary Fibrous Tumor in the Preperitoneal Space Mimicking an Intra-Abdominal Tumor

Solitary fibrous tumors (SFTs) are uncommon fibroblastic mesenchymal neoplasms that rarely metastasize. They were primarily considered intrathoracic tumors; however, recent studies have reported SFTs in extrathoracic locations. This report describes a rare case of an SFT in the preperitoneal space that mimicked an intra-abdominal tumor radiographically. A 67-year-old woman was diagnosed with an extrahepatic tumor through ultrasonography. Computed tomography revealed a nodule near the liver's left lobe at the upper abdominal midline. Laparoscopic tumor resection was performed to minimize undersampling and tumor seeding. Laparoscopy revealed a well-circumscribed tumor located in the preperitoneal space. The tumor was resected en bloc with a macroscopically negative margin. Histopathological examinations confirmed an SFT using immunohistochemistry. Adjuvant treatment was not administered. No residual lesions were reported at the 6-month and 1-year follow-ups. Although SFT rarely metastasizes, early diagnosis and treatment of SFTs should be emphasized to ensure optimal patient outcomes.

Novel Manifestation of Retinal Hemangioblastomas Detected by OCT Angiography in von Hippel-Lindau Disease

To elucidate the clinical characteristics of atypical retinal vascular proliferation in patients with von Hippel-Lindau (VHL) disease using OCT angiography (OCTA). Prospective, observational study. Fifty-seven consecutive patients with a diagnosis of VHL disease who visited Kyoto University Hospital between January 2019 and March2022. Retinal hemangioblastomas (RHs) were assessed using multimodal imaging including OCTA. Retinal hemangioblastomas were classified into 2 phenotypes: nodular and flat. Nodular RHs were defined as typical RHs that were globular, well-circumscribed tumors, often accompanied with dilated feeder arterioles and draining venules. Flat RHs lacked a protruded red or colored mass, had variable and indistinct borders, and were not accompanied with feeder and draining vessels. The prevalence, distribution, and description of atypical flat RHs. Among 57 consecutive patients with VHL disease, 37 patients (64.9%) showed RHs in at least 1 eye. Bilateral RHs were seen in 23 patients (62.2%). Among 58 eyes of 37 patients with RHs, typical nodular RHs were detected in 54 eyes. Nodular RHs were seen mainly in the peripheral retina and occasionally in the peripapillary region, and they showed exudative changes in some cases. Flat RHs were detected in 7 eyes (12.1%). Four eyes showed only flat RHs, and 3 eyes showed both types in the same eye. Most flat RHs appeared as retinal hemorrhages or faint flat abnormal retinal vessels in the inner retina on the fundus examination, often within the macula area or peripapillary. In all eyes with flat RHs, OCTA showed abundant blood flow in the lesions. OCT revealed that flat RHs were seen mainly between the retinal nerve fiber layer and the ganglion cell layer, and occasionally within the inner nuclear layer. During a mean follow-up period of 20.4 ± 15.0 months, no flat RHs accompanied exudative change, tractional retinal detachment, or progression in size. Patients with VHL disease can demonstrate 2 distinct types of RHs: the classic nodular type and an atypical flat type. OCT angiography can be useful in improving the detection of atypical flat RHs, which can be difficult to detect clinically. Proprietary or commercial disclosure may be found after the references.

Subtle magnetic resonance imaging differences in tegmental pilocytic astrocytomas as a caution against attempting gross-total resection: illustrative cases.

Although surgery within the tegmentum of the midbrain is challenging, resection of tegmental pilocytic astrocytomas (PAs) is a standard treatment because this has been shown to outperform chemotherapy and radiotherapy in terms of long-term tumor control. Gross total resection (GTR) assisted by intraoperative neuroelectrophysiological monitoring can be achieved with a reasonable risk-to-benefit ratio, especially for well-circumscribed tumors, but careful scrutiny of magnetic resonance imaging (MRI) is critical to surgical decision making. The authors present two cases of tegmental PAs, which appeared grossly similar on MRI and were operated on via the same surgical approach using the same intraoperative adjuncts. The tumors had identical histopathological and molecular diagnoses but drastically different functional outcomes for the patients, with significant long-term complications for one of the children, which the authors believe was due to a slightly more invasive nature of this tumor. The authors demonstrate subtle preoperative MRI findings that might be potential clues to a more infiltrative nature of one PA versus another and present pathological findings supporting this argument. This report serves as a reminder that not all tegmental PAs can be managed by the same surgical approach. Subtle signs of infiltration may indicate that GTR should not be attempted.