CT and MR imaging findings of sinonasal angiomatous polyps

Sphenopalatine artery pseudoaneurysm masquerading as a second primary maxillary carcinoma

PURPOSE

Maxillary sinus carcinomas usually present as a locally advanced disease at the time of diagnosis and it is extremely unusual to have a second primary maxillary carcinoma on the contralateral side after many years of completion of treatment of the first malignancy. We present here a case report of a sphenopalatine artery (SPA) pseudoaneurysm mimicking the second primary maxillary carcinoma.

METHODS

We reviewed the literature for SPA pseudoaneurysm.

RESULTS/CASE REPORT

This report describes the case of a 90-year-old man with a background of adenoid cystic carcinoma of the right maxillary sinus, diagnosed and treated with surgery and radiotherapy 14 years ago, who presented with a history of multiple episodes of epistaxis. The radiological evaluation showed a heterogeneously enhancing mass with a central hemorrhagic component and surrounding bony erosions in the left maxillary sinus and the patient was planned for biopsy from the suspicious mass along with SPA ligation. However, on opening the maxillary antrum there was excessive bleeding and it was determined unsafe to proceed further. The patient was subsequently taken to interventional radiology for diagnostic angiography which revealed an SPA pseudoaneurysm that was subsequently embolized successfully.

CONCLUSIONS

Sphenopalatine artery pseudoaneurysms should be considered as a differential for recurrent epistaxis in patients with a history of sinonasal malignancy. In such cases, endovascular embolization is a viable management option.

Sinonasal Angiomatous Polyp: A Case Report and Review of Literature

Sinonasal angiomatous polyp (SAP) is a benign pseudoneoplastic lesion rarely reported in the literature. It may be misdiagnosed as a malignant neoplasm due to its aggressive features of bone erosion clinically or on imaging. We report the case of a 43-year-old woman with a 3 month history of unilateral nasal obstruction with recurrent epistaxis. Nasal endoscopy showed polypoid nasal mass occupying the left nasal cavity. Imaging was suggestive of malignant vascular tumor. The patient underwent surgical excision after embolization. Histopathology concluded to the diagnosis of SAP.

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.

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.

Computed tomography and magnetic resonance imaging of adenoid cystic carcinoma in the maxillary sinus: a retrospective study with radiologic-histopathologic correlations

OBJECTIVE

The aim of this study was to investigate computed tomography (CT) and magnetic resonance imaging (MRI) findings in adenoid cystic carcinoma (ACC) in the maxillary sinus and their correlations with the tubular, cribriform, and solid histopathologic types of ACC.

STUDY DESIGN

Twenty cases of histopathologically proven ACC in the maxillary sinus were retrospectively reviewed. CT and MRI findings were correlated with histopathologic results.

RESULTS

On CT, significant differences were discovered among the 3 histopathologic ACC types in range, size, shape, margins, type of bone destruction, and time intensity curve (TIC) (P ≤ .018). Tubular lesions were limited in range, were smaller than the other types, produced small cystic patterns with well-defined margins, and caused a cribriform pattern of bone destruction. All tumors demonstrated heterogeneous intensity signal on T1- and T2-weighted images (T1WI and T2WI) and appeared as hypo- or isointense small cystic lesions on T1WI and hyperintense on T2WI (n = 6). Postcontrast MRI revealed marked heterogeneous enhancement for all lesions. The TIC showed a rapidly enhancing and slow washout pattern in all tubular lesions and a rapidly enhancing and rapid washout pattern in solid tumors.

CONCLUSIONS

Different histologic patterns of ACCs have distinctive radiologic features, which can facilitate accurate preoperative diagnosis.

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.

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.

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.