Angiectatic nasal polyps that clinically simulate a malignant process: report of 2 cases and review of the literature

Angiomatous Polyp Originating From the Inferior Turbinate: A Variant of the Sinonasal Polyp

Angiomatous polyps are an uncommon subtype of sinonasal polyps, characterized by extensive vascular proliferation and ectasia. The authors report the first case of angiomatous polyp originating from the inferior turbinate, which is a variant of the sinonasal polyp.

Large Angiomatous Nasal Polyp Presents With Epistaxis Imitating Juvenile Nasopharyngeal Angiofibroma

An angiomatous nasal polyp is a rare subtype of sinonasal polyp that is commonly found in the middle meatus and characterized by the presence of blood vessels within polyp tissue. It is a benign lesion but is prone to misdiagnosis as a malignant tumor because it typically grows larger and is more vascular than other types of polyps. In this report, a 16-year-old male with no significant past medical history presents with a six-month history of epistaxis and progressive nasal obstruction. Examination of the oral cavity showed a centrally located soft palate mass. CT maxillofacial with contrast showed a hypervascular 3.4 x 4.7 x 6.1 cm mass in the nasal cavity extending through the nasal choanae and down to the level of the tongue. MRI showed a heterogenous polypoid mass originating from the left middle meatus vs. nasal cavity, with characteristics favoring an aggressive tumor. The patient was taken for interventional radiology (IR) embolization and nasal endoscopy. Biopsy showed the left nasal mass contained granulation tissue and the palatal mass consisted of necrotic tissue. He was taken for second-stage endoscopic sinus surgery with plans for extensive reconstruction if necessary. Extensive polyposis was found without gross evidence of an aggressive tumor. The anterior polyposis was debulked and the polyp was cut at its root to allow for removal of the nasopharyngeal/oropharyngeal portion through the mouth. He was able to be discharged on the same day and his postoperative recovery was uncomplicated. Angiomatous nasal polyps are uncommon, share features of aggressive tumors on imaging, and require angiography and biopsy to safely rule out malignancy. Endoscopic surgical resection typically results in good outcomes and low recurrence rates.

Angiectatic nasal polyps with pleomorphism ‒ a diagnostic pitfall

OBJECTIVE

To generalise the features of PANP in case of potential clinical and pathological pitfall of diagnosis.

METHODS

Thirteen patients diagnosed as PANP were retrospectively analyzed in the Pathology Department of Capital Medical University from August 2014 to December 2019. Immunohistochemical staining with CD34, CK, Vim, Calponin, Ki67, Bcl-2, and STAT-6 was performed with envision-two steps method.

RESULTS

PANP is a benign tumor presenting with gross variegated tan to gray soft fleshy tissue with foci of obvious hemorrhage and necrosis. The imaging shows internal heterogeneous hyperintensity with a peripheral hypointense rim while postcontrast images display a strong nodular and patchy enhancement. Vimentin (Vim) stain was consistently positive, while negative for CD34, STAT-6 and Bcl-2 (focal positive in two cases). Calponin and CK stain was positive in nine cases, respectively.

CONCLUSION

PANP is a clinically rare tumor which may simulate malignancy lesion. Recognizing of characteristic features in these thirteen patients would be beneficial to avoid misdiagnosis and unnecessary aggressive treatment.

LEVEL OF EVIDENCE

This work was Level 2 of evidence according to the Guide for Authors.

Angiomatous Nasal Polyp: The Great Emulator-A Case Report

Angiomatous nasal polyps are rare, benign and non-neoplastic lesions rarely reported in literature. Clinically and radiologically it mimics sinonasal neoplasm. In 5% of inflammatory or allergic sinonasal polyps, extensive vascularisation and ectasia with pseudoamyloid deposition is noted. Pathognomic features of ANP are angiogenesis, accumulation of amorphous eosinophilic substance and atypical stromal cells. In this case report we elaborate probable etiology, clinical features, histopathology (HPE) and radiological findings in a unique case of ANP which mimicked sinonasal mass. Patient presented with U/L nasal obstruction and recurrent episodes of epistaxis. He was operated for similar complaints 8 years ago, details of which were not available with the patient. Patient was recently diagnosed with Hypertension (HTN) and Diabetes Mellitus (DM). On Diagnostic Nasal endoscopy and Radiological imaging, the nasal mass appeared to be a sinonasal vascular lesion. Revision Functional endoscopic sinus surgery was done and on HPE, ANP was reported. Thus, we conclude that ANPs are rare pathological entity and can cause a significant diagnostic dilemma. Thorough knowledge about the clinical presentation and histopathological features is important in establishing an early definitive diagnosis. Also we have made an attempt to establish the possible role of DM and HTN in pathophysiology of ANP.

Management of Angiomatous Antrochoanal Polyp: Our Experience

Antrochoanal polyps are the most common type of choanal polyp. Angiomatous polyp is a rare subtype of Antrochoanal polyp that might be misdiagnosed as malignant lesion due to its clinical features. A retrospective observational study was conducted in a tertiary care hospital in patients who were diagnosed with Angiomatous Antrochonal polyp that underwent functional endoscopic sinus surgery from 2017 to 2020. We analyzed the clinical symptoms, radiological findings, and pathological features of all patients diagnosed with Angiomatous Antrochonal polyp. Unilateral nasal obstruction, rhinorrhea, and epistaxis were the common symptoms. Antrochoanal polyps all originated from maxillary sinus and extended to nasal cavity with or without involving the nasopharynx. Expansile mass with surrounding bony destruction are typical on computed tomography imaging but specific for Angiomatous Antrochoanal polyp. The magnetic resonance revealed high signal intensity on T1-weighted images and hypo-intense rim on T2-weighted images. Computed tomography and magnetic resonance together might give rise to more accurate diagnosis of Angiomatous Antrochoanal polyp. Incisional biopsy does help if the clinician suspects a malignant lesion. Complete removal is treatment of choice for Angiomatous Antrochoanal polyp.

Angiomatous Nasal Polyp Diagnosed by Preoperative Imaging and Successfully Resected by Endonasal Endoscopic Surgery: A Case Report

Angiomatous polyp is a benign, nonneoplastic nasal polyp that accounts for 4-5% of all inflammatory nasal polyps but is rarely reported in the literature. It can grow rapidly and exhibit an aggressive clinical behavior that can simulate malignant sinonasal tumor. We herein report a case of a 13-year-old boy with a rapidly growing angiomatous polyp in the nasal cavity. We had followed up the patient without significant changes for two years, but the tumor had rapidly grown in the last six months. At first, the rapid growth of the tumor and the bone erosion of the maxilla were suggestive of a malignant tumor. However, with preoperative magnetic resonance imaging (MRI) and [18F]-2-fluoro-2-deoxy-D-glucose positron emission tomography imaging findings, we established the corrective diagnosis of an angiomatous polyp. After the diagnostic imaging, we performed an endoscopic endonasal surgery and totally resected the tumor without unnecessary excessive surgery. Recognition of this disease that can mimic malignancy is important to avoid excessive surgery such as en bloc resection by craniofacial approach, and we believe that MRI findings can be helpful for the imaging diagnosis.

Angiectatic Sinonasal Polyp: A Diagnostic Challenge

Sinonasal angiectatic polyp is an uncommon condition with features that masquerade various pathologies like hemangioma, angiofibroma, inverted papilloma, malignancy. We report a case of a left-sided vascular nasal mass, which on examination and investigations suggested cavernous hemangioma of the left maxillary sinus, whereas histopathology post-excision revealed angiectatic polyp.

Clinical and Pathological Features of Angiomatous Nasal Polyps: A Report of Four Cases and Review of Literature

Inflammatory or allergic sinonasal polyps are characterized by extensive vascular growth and ectasia with deposition of pseudoamyloid in 5% of cases. Angiomatous nasal polyp (ANP) is a relatively rare benign lesion, which may be misdiagnosed as a benign or malignant tumor. The characteristic pathological features of ANP are expanded angiogenesis, accumulation of extracellular amorphous eosinophilic substance, and atypical stromal cells. This report aimed to outline the histological differential diagnosis of ANP. Through a full histopathological examination, we studied biopsies and resected specimens from five patients who were diagnosed with ANPs, including one with facial deformity. Gross findings showed that tumors were firm in consistency, lobulated on the surface, and lined by partially ulcerated mucous membrane. Light microscopy showed clusters of widened, thin-walled blood vessels among congo red-negative eosinophilic substance with an area of necrosis and irregular stromal spindle cells. Presence of endothelial cell myofibroblasts were confirmed by electron microscopy and immunohistochemistry. This is a report of four cases which showed extreme examples of ANPs that was completely resected by endoscopic sinus surgery for all patients. A full histopathological examination is recommended to confirm the possible differential diagnoses for a better management plan.

Massive Angiomatous Nasal Polyp Mimicking Nasopharyngeal Angiofibroma

Angiomatous Nasal polyps is the rarest entity amongst the various types of nasal polyps known. It presents as mass filling the nasal cavity with extensions into surrounding structures; patients often presenting with symptoms of nasal obstruction and epistaxis, thus, mimicking nasal angiofibromas or malignancies. Here, we present a case of 16-year-old male, with complaints of unilateral nasal obstruction, intermittent epistaxis, anosmia, headache, ipsilateral epiphora and facial swelling. Further examination and investigations favoured a diagnosis of an angiomatous polyp with extension into surrounding structures. Surgical excision was carried out. Histopathological studies on the excised specimen were in line with the preoperative diagnosis. The patient remains disease free at a follow of 1 year.

Evaluation of multiparametric MRI differentiating sinonasal angiomatous polyp from malignant tumors

PURPOSE

Sinonasal angiomatous polyps (SAPs) can be misdiagnosed as malignant tumors due to aggressive clinical behaviors. The purpose of this study was to evaluate the diagnostic accuracy of multiparametric MRI in differentiating SAPs from malignant tumors.

METHODS

This retrospective study included 31 patients with pathologically proven SAPs and 36 patients with malignant tumors in maxillary sinus and nasal cavity. All the patients underwent conventional MRI and dynamic contrast-enhanced (DCE) MRI on 3T MR scanners. Diffusion-weighted (DW) MR imaging was performed in 45 patients. All the MR images were retrospectively analyzed independently by two authors.

RESULTS

Significant differences were found in T1 homogeneity, T2 signal intensity ratio, peripheral hypointense rim on T2WI, and soft tissue infiltration between SAP and malignant tumors (P = 0.004, < 0.001, < 0.001, and = 0.001, respectively). SAPs usually show heterogeneous signal intensity on T1WI, peripheral hypointense rim on T2WI, and higher T2 signal intensity ratio. The tumor size of SAP (4.01 ± 1.08 cm) was slightly smaller than that of malignant tumors (4.56 ± 1.12 cm) (P = 0.045). There were significant differences in DCE-MRI parameters including Tpeak, CImax, WR, TIC types, and progressive enhancement (P = 0.009, < 0.001, = 0.001, = 0.001, and < 0.001, respectively) between SAPs and malignant tumors. All the 31 SAPs showed progressive enhancement on DCE-MRI, while none of the malignant tumors showed progressive enhancement (accuracy 100%). The mean ADC of SAP (1.75 ± 0.30 × 10^-3 mm²/s) was higher than that of malignant tumors (1.18 ± 0.31 × 10^-3 mm²/s) (P < 0.001).

CONCLUSION

Multiparametric MRI showed high diagnostic performance in differentiating SAPs from malignant tumors. Progressive enhancement on DCE-MRI is the most effective feature of SAP.

The clinicopathological features of sinonasal angiomatous polyps

BACKGROUND

Sinonasal angiomatous polyp (SAP) is a rare subtype of sinonasal polyp that might be misdiagnosed as a malignant lesion due to its clinical symptoms.

METHODS

We retrospectively enrolled the patients who were diagnosed with SAP in our hospital during 2008-2015. We analyzed the clinical symptoms, radiological findings, and pathological features of all patients diagnosed with SAP.

RESULTS

Unilateral nasal obstruction, rhinorrhea, and epistaxis were the common symptoms. SAPs all originated from maxillary sinus and extended to nasal cavity with or without involving the nasopharynx. Expansile mass with surrounding bony destruction is typical on computed tomography imaging but specific for SAPs. The magnetic resonance revealed high signal intensity on T1-weighted images and hypointense rim on T2-weighted images.

CONCLUSION

Computed tomography and magnetic resonance together might give rise to more accurate diagnosis of SAP. Incisional biopsy does help if the clinician suspects a malignant lesion. To treat SAP, complete removal is the optimal choice.

Sphenoid sinus organized hematoma with cranial neuropathies masquerading as a malignancy: A case report

Sinonasal organized hematoma (SNOH) is rarely encountered in clinical practice. The disease demonstrates a high tendency for occurrence in East Asian individuals, and in the majority of cases, is located in the maxillary sinus. The current report presents the case of an 81-year-old female who developed a space-occupying lesion, which masqueraded as a skull base malignancy, following surgery for the treatment of isolated sphenoid sinus aspergilloma. Subsequent endoscopic endonasal surgery confirmed the diagnosis of an OH of the sphenoid sinus. The patient recovered from all neurological deficits within two months, with the exception of the loss of visual perception. Although SNOH presents a diagnostic challenge, when physicians possess knowledge of its typical imaging features, this facilitates the achievement of a correct diagnosis and the prescription of optimal treatment.

Organized Hematoma: An Analysis of 84 Cases with Emphasis on Difficult Prediction and Favorable Management

OBJECTIVE

To characterize features of organized hematoma (OH) that may cause considerable diagnostic difficulties.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary medical center.

SUBJECTS AND METHODS

Eighty-four patients with pathologically confirmed OH over a 10-year period were retrospectively reviewed for clinical features, imaging findings, pathologic characteristics, and treatment modalities.

RESULTS

This study included 39 males and 45 females who presented with frequent epistaxis and nasal obstruction. There were 62 (74%) patients >40 years old (mean, 50; range, 9-81). OH mainly originated in the maxillary sinus (n = 82) or nasal cavity (n = 2) unilaterally, and most were expansile masses (n = 73) that extended into nasal cavity (n = 71) or choanae (n = 17). Several lesions were locally aggressive and simulated a malignant process that involved the ethmoid sinus (n = 22), orbit (n = 11), pterygopalatine fossa (n = 16), infratemporal fossa (n = 9), cheek (n = 3), and hard palate (n = 3). Internal architecture on computed tomography (CT) scans showed OH with expansile remodeling of the maxillary wall (82.1%) and smooth bony destruction (70.2%), whereas T2-weighted magnetic resonance (MR) images showed inhomogeneity with a notable hypointense peripheral rim in all lesions. CT and MR contrast-enhanced images revealed patchy heterogeneous enhancement that could be interpreted according to histopathologic findings of hemorrhage and neovascularization. OH was successfully removed with endoscopic surgery, although 5 cases recurred.

CONCLUSIONS

OH can be successfully treated by endoscopic surgery. CT and MR examination provide characteristic findings for prediction and careful surgical planning.

Sinonasal Angiomatous Polyp: Evaluation With 2-Phase Helical Computed Tomography

Sinonasal angiomatous polyp (SAP) is a rare benign nontumorous lesion and previously considered lack of characteristic computed tomography (CT) findings. This study aimed to evaluate 2-phase helical CT for characterization of SAP. Twelve patients with pathologically confirmed SAP underwent 2-phase helical CT preoperatively. After injection of 80 mL contrast material at a rate of 3 mL/s, early and delayed phases were obtained with delays of 30 and 120 s, respectively. The degree and pattern of enhancement were visually analyzed. The attenuation changes were also analyzed quantitatively by measuring CT values and compared with those of the internal maxillary artery (IMA). All 12 cases showed vessel-like marked heterogeneous enhancement at both early and delayed phases. An irregular linear, nodular, and patchy enhancement pattern was found at the early phase, and enlarged and fused together, that is, progressive enhancement pattern was found at the delayed phase. There was no significant difference between the CT values of SAP and those of the IMA at the plain, arterial phase, and delayed phase (53 ± 6 Hounsfield units [HU] vs 56 ± 7 HU, 187 ± 56 HU vs 209 ± 71 HU, and 143 ± 22 HU vs 139 ± 19 HU, respectively, P = 0.361, 0.429, and 0.613, respectively). Vessel-like marked heterogeneous enhancement was a characteristic CT feature of SAP, and progressive enhancement on 2-phase helical CT could further convince the diagnosis.

CT and MR imaging findings of sinonasal angiomatous polyps

OBJECTIVE

To characterize the CT and MR imaging findings of patients with sinonasal angiomatous polyps (SAPs) and evaluate their respective clinical value in the diagnosis of SAP.

METHODS

CT and MR imaging findings of 15 patients with pathologically proven SAP were examined. Assessed image features included location, size, margin, attenuation, and change of the bony walls of the sinonasal cavity on CT, and signal intensity and enhancement pattern on MR.

RESULTS

On CT, the SAP was mostly isoattenuated with patches of slight hyperattenuation. Most lesions caused changes in the adjacent bone, including expansile remodeling (n=8), defect or destruction (n=7), and hyperostosis (n=6). All lesions examined by MR showed heterogeneous isointense signal intensity on T1-weighted images and mixed obvious hyperintense and hypointense signal intensity with linear hypointense septum internally (n=10), and hypointense peripheral rim on T2-weighted images (n=10). Postcontrast MR images demonstrated areas of heterogeneous and marked enhancement with an unenhanced hypointense rim and septa (n=7).

CONCLUSIONS

CT and MR imaging have respective advantages in the diagnosis of SAP. Combined application of CT and MR examinations is necessary for patients with suspected SAP.

Correlation of computed tomography with pathological features in angiomatous nasal polyps

Background

Angiomatous nasal polyps (ANPs), also known as angiectatic polyps, have rarely been reported in the literature. ANPs are characterized by extensive vascular proliferation and ectasia. ANPs can grow rapidly and exhibit aggressive clinical behavior that could simulate malignancy preoperatively, and they are easily confused with other diseases. In the present study, we analyzed the correlation between the computed tomography (CT) findings of nasal angiomatous polyps and their pathological features.

Methods

We evaluated CT findings and pathological features of 31 surgically proven ANPs.

Results

The study population included 16 males and 15 females aged between 27 and 81 years (mean age, 53.5 years). On CT, the masses were heterogeneous; they had a soft tissue density and filled the maxillary and/or nasal cavities. Calcifications were found in 2 of the 31 cases. The lesions showed a clear boundary (15/31). The low-density shading on CT was related to the inflammatory, necrotic, and cystic changes, and the high-density shading on CT was related to hemorrhagic areas of the mass. On contrast-enhanced CT, the center of the lesions was non-enhanced with peripheral intensification due to occlusion or compression of feeder vessels of the polyp center, and the inflammatory cells and neovascularization around the edge of the mass. The most common site of maxillary wall erosion was the medial wall (21/31), followed by the posterior lateral wall (3/31), upper wall (2/31), and septum (3/31). Of these, the nasal cavity and/or maxillary sinus were enlarged in 28 cases. These findings were associated with the chronic progress of nasal angiomatous changes.

Conclusions

CT of ANPs may demonstrate benign bone changes associated with the lesions and may also reflect the fact that ANPs do not invade peripheral soft tissue. CT demonstrated these lesions consistently and provided information useful for surgical planning.

MR evaluation of sinonasal angiomatous polyp

BACKGROUND AND PURPOSE

SAP is a rare lesion of the sinonasal cavity, which may be misdiagnosed as a benign or malignant neoplasm. The purpose of our study was to comprehensively evaluate the MR imaging features of SAP.

MATERIALS AND METHODS

Forty patients with SAP confirmed pathologically were retrospectively reviewed. Of the 40 patients undergoing MR imaging, 39 had postcontrast T1WI; 30, DCE MR imaging; and 17, DWI. The image features assessed included the location, shape, margin, size, signal intensity, and enhancement pattern on DCE MR imaging and ADC maps.

RESULTS

All 40 SAPs originated from the maxillary sinus, but the lesions frequently extended into the ipsilateral nasal cavity (38/40), toward the choana (19/40), and into the nasopharynx (8/40). The lesions demonstrated hypointensity on T1WI and heterogenous hyperintensity on T2WI. All 40 lesions showed a peripheral hypointense rim on T2WI. Postcontrast MR imaging revealed marked heterogeneous nodular and patchy enhancement. Progressive enhancement was found on DCE MR imaging in 30 cases. The TIC showed a steady enhancement pattern in 3 cases, a rapidly enhancing and slow washout pattern in 6 cases, and a rapidly enhancing and rapid washout pattern in 21 cases. On DWI, the mean ADC value was (1.40 ± 0.20) × 10(-3) mm(2)/s.

CONCLUSIONS

Distinctive features of SAP on conventional MR imaging include internal heterogeneous hyperintensity and a peripheral hypointense rim on T2WI, as well as strong nodular and patchy enhancement on postcontrast MR images. The progressive enhancement on DCE MR imaging can also suggest the diagnosis.

Rare nasal tumours in kumaon region of uttarakhand: a clinical observation

To review the cases of nasal mass in the Kumaon region of Uttarakhand and observe the incidence of rare nasal tumours and their atypical presentation. A prospective study conducted at ENT dept of STMF Hospital & U.F.H.T medical college at Haldwani in the Nainital district of Uttarakhand. This state has approx.ninty lacs of population out of which 50 %resides in Kumaon region. hence this should be taken as a sample study and considering the topographical condition of this region this is the only one medical college where facilities like CT Scan and MRI are available so most of the patients of this region are referred to this medical college. Cases were selected from the patients attending ENT OPD with nasal mass during the period of August 2005-Sep 2008. History and physical examination were done according to a proforma. All patients were routinely investigated. CT Scan of nose and PNS were done in each case. Biopsy along with immunohistochemistry (if required) were done in each case. Out of 160,136 patients attending the ENT OPD of the hospital during the period of August 2005-September 2008, of which total 200 (0.1241)% patients presenting with nasal mass were included in the study. Age of the patient ranged from 5 to 70 years. Maximum patients were seen in the age group of 31-40 (37%) The most common symptom was nasal blockage (97.5%). The most common tumour was squamous papilloma (90%). Here we are describing the presentation and abnormal features of some of the rare nasal tumours, which comprised only 4.5% (9 cases) of the 200 patients of nasal mass seen during the period. In the Kumaon region of Uttarakhand patients with tumours of nose and paranasal sinuses usually present late to the clinician due to poverty and ignorance. Their presentation was variable and many times disease was highly advanced. If proper diagnostic facilities are available in the region, timely intervention can be done and maximum benefit can be extended to the patient.

Soft Tissue Pseudosarcomas

Soft tissue pathology is one of the most challenging areas of diagnostic pathology, not only because of the morphologic diversity of such lesions, but also because of their rarity and pathologists' subsequent lack of exposure to these tumors. Many lesions mimic malignant mesenchymal neoplasms, collectively referred to as "pseudosarcomas." The list of proliferations that can simulate a sarcoma is extensive and heterogeneous. This review addresses malignant, nonmesenchymal neoplasms; mesenchymal neoplasms that histologically mimic sarcomas but are benign; and benign reactive soft tissue lesions that are neither neoplastic nor malignant, but have worrisome clinical and/or morphologic features.

Radiofrequency-induced thermotherapy of nasopharyngeal angiofibroma and immunohistochemical analysis of vessel proliferation: a case report

Introduction

Nasopharyngeal angiofibroma presents with symptoms of nasal obstruction and epistaxis. The treatment of choice is embolization followed by surgery.

Case presentation

A 52-year-old man underwent surgery for nasopharyngeal angiofibroma after adjuvant radiofrequency-induced thermotherapy. To the best of the authors' knowledge, this is the first case of angiofibroma with clinical follow-up after thermocoagulation therapy supported by quantitative, double immunohistochemistry. We found this case of angiofibroma to be of interest owing to the presentation of symptoms leading to biopsy, the pathohistological observations obtained with synchronous Ki67/cluster of differentiation 34 and Ki67/smooth muscle actin immunohistochemistry and high pericyte proliferation.

Conclusion

Coagulation of angiofibroma vessels followed by acquisition of a thick mantle of pericytes in a patient with a nasopharyngeal growth suggests that radiofrequency-induced thermotherapy could be a useful, palliative therapy for bleeding nasopharyngeal angiofibroma, supporting vessel maturation prior to surgical tumor removal.

Infarcted angiomatous nasal polyps

Angiomatous nasal polyps are a rarely reported subtype of inflammatory sinonasal polyps that are characterized by extensive vascular proliferation and ectasia. Compromise of their vascular supply may occasionally lead to infarction, resulting in clinical, radiological and pathological features that simulate a neoplastic process. In the present paper, the salient characteristics of this unusual entity are described. The clinical, radiological and pathological features of two patients with infarcted angiomatous nasal polyps are presented. Grossly, the polyps had an unusual inhomogenous appearance and texture and were associated with a foul odor. CT findings included bony expansion and destruction. MRI findings included markedly inhomogenous contrast enhancement on T1-weighted images. Histopathologically, both cases showed abundant vascular ectasia, with widespread intraluminal thrombosis and necrosis. Recanalization and reparative changes were also present. Angiomatous nasal polyps are poorly documented in the literature. Although entirely benign, they may simulate neoplastic processes, thus awareness of their existence is of considerable importance.