Differential diagnosis of sinonasal extranodal NK/T cell lymphoma and diffuse large B cell lymphoma on MRI

Sinonasal NK/T-cell lymphoma - imaging features overlap with non-neoplastic etiologies

PURPOSE

The purpose of this retrospective study is to evaluate imaging features of sinonasal NK/T-cell lymphoma, potentially aiding early diagnosis and improving patient outcomes through timely biopsy evaluation and treatment.

MATERIALS & METHODS

This study was designed as a retrospective review. Imaging characteristics in a total of 28 patients with histology confirmed sinonasal NK/T-cell lymphoma were evaluated by two radiologists. Demographic data and clinical features were extracted from the electronic medical record.

RESULTS

Among 28 patients, 84.6% presented with nasal cavity involvement and 88.5% with an isoattenuating lesion on CT and 63.6% with T2 hypointensity on MRI. Notably, 57.7% showed osseous destruction and 27.3% had devascularized tissue, highlighting significant radiologic features that may overlap with non-neoplastic etiologies.

CONCLUSION

Sinonasal NK/T-cell lymphoma should be in the differential diagnosis in patients presenting with chronic sinonasal symptoms and imaging findings of tissue necrosis, osseous destruction, and adjacent fat infiltration. Imaging features overlap with entities such as aggressive fungal sinusitis and granulomatosis with polyangiitis.

Comparative Analysis of the Clinical Manifestations of Sinonasal Natural Killer T-Cell Lymphoma and Diffuse Large B-Cell Lymphoma

Background and Objectives

Natural killer T-cell lymphoma (NKTCL) and diffuse large B-cell lymphoma (DLBCL) are the two most prevalent subtypes of lymphoma in the sinonasal region. Accurately differentiating between sinonasal DLBCL and NKTCL is crucial for determining the appropriate treatment and prognosis. The present study compared the clinical characteristics of these two conditions.

Methods

We conducted a retrospective review of 173 patients diagnosed with sinonasal lymphoma at a single institute between 2004 and 2017. This review included only patients with DLBCL and NKTCL who had more than 6 months of follow-up records. We analyzed patient data encompassing clinical characteristics, pathologic findings, radiologic findings, treatment modalities, recurrence, and survival.

Results

Among the patients analyzed, 117 patients were diagnosed with NKTCL and 45 with DLBCL. Endoscopic evaluation revealed a significantly higher incidence of crusting (p<0.001) and necrotic lesions (p=0.001) in patients with NKTCL, whereas polypoid masses were more commonly observed in patients with DLBCL (p<0.001). Computed tomography (CT) scans indicated no significant differences in bilaterality or bone destruction between the two groups. The DLBCL group exhibited a higher rate of concurrent lymph node or organ involvement than the NKTCL group (p<0.001). The 5-year overall survival rate was 67.4% for DLBCL and 69.1% for NKTCL, with no significant difference between the two.

Conclusion

Clinical differences exist between sinonasal DLBCL and NKTCL in terms of endoscopic and CT findings. These distinct characteristics can aid in distinguishing between the two types of sinonasal lymphoma during clinical diagnosis.

International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors

BACKGROUND

Sinonasal neoplasms, whether benign and malignant, pose a significant challenge to clinicians and represent a model area for multidisciplinary collaboration in order to optimize patient care. The International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors (ICSNT) aims to summarize the best available evidence and presents 48 thematic and histopathology-based topics spanning the field.

METHODS

In accordance with prior International Consensus Statement on Allergy and Rhinology documents, ICSNT assigned each topic as an Evidence-Based Review with Recommendations, Evidence-Based Review, and Literature Review based on the level of evidence. An international group of multidisciplinary author teams were assembled for the topic reviews using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses format, and completed sections underwent a thorough and iterative consensus-building process. The final document underwent rigorous synthesis and review prior to publication.

RESULTS

The ICSNT document consists of four major sections: general principles, benign neoplasms and lesions, malignant neoplasms, and quality of life and surveillance. It covers 48 conceptual and/or histopathology-based topics relevant to sinonasal neoplasms and masses. Topics with a high level of evidence provided specific recommendations, while other areas summarized the current state of evidence. A final section highlights research opportunities and future directions, contributing to advancing knowledge and community intervention.

CONCLUSION

As an embodiment of the multidisciplinary and collaborative model of care in sinonasal neoplasms and masses, ICSNT was designed as a comprehensive, international, and multidisciplinary collaborative endeavor. Its primary objective is to summarize the existing evidence in the field of sinonasal neoplasms and masses.

Clinical characteristics analysis of sinonasal diffuse large B-cell lymphoma and extranodal NK/T-cell lymphoma

KEYPOINTS

Extranodal NK/T-cell lymphoma (ENKL) was the most common sinonasal lymphoma at our hospital. ENKL occurs at a younger age, and is more prevalent in the nasal cavity. ENKL had a lower Ann Arbor stage, and a better prognosis than diffuse large B-cell lymphoma (DLBLC).

Primary Plasmablastic Lymphoma of The Paranasal Sinuses: A Rare Case Report

Plasmablastic lymphoma (PBL) is a rare and highly invasive type of non-Hodgkin's lymphoma. It is usually associated with immunosuppression and human immunodeficiency virus infection. PBL most commonly occurs in the oral cavity, lymph nodes, and in other extranodal sites. However, it rarely originates from bilateral sinuses. Herein, we report the case of a 59-year-old man diagnosed with primary PBL of the sinuses confirmed by endoscopic biopsy, imaging materials, histopathological examination, and immunohistochemistry. The patient underwent 4 cycles of chemotherapy and 22 rounds of radiation therapy for 8 months. Re-examination by sinus computed tomography revealed no obvious tumor tissue in the nasal cavity and sinuses, suggesting that treatment was effective. No local recurrence or distant metastasis was detected at 6-month follow-up after the end of treatment.

PET/CT Imaging in Treatment Planning and Surveillance of Sinonasal Neoplasms

Sinonasal cancers are uncommon malignancies with a generally unfavorable prognosis, often presenting at an advanced stage. Their high rate of recurrence supports close imaging surveillance and the utilization of functional imaging techniques. Whole-body 18F-FDG PET/CT has very high sensitivity for the diagnosis of sinonasal malignancies and can also be used as a "metabolic biopsy" in the characterization of some of the more common subgroups of these tumors, though due to overlap in uptake, histological confirmation is still needed. For certain tumor types, radiotracers, such as 11C-choline, and radiolabeled somatostatin analogs, including 68Ga-DOTATATE/DOTATOC, have proven useful in treatment planning and surveillance. Although serial scans for posttreatment surveillance allow the detection of subclinical lesions, the optimal schedule and efficacy in terms of survival are yet to be determined. Pitfalls of 18F-FDG, such as post-surgical and post-radiotherapy crusting and inflammation, may cause false-positive hypermetabolism in the absence of relapse.

Malignant and Nonmalignant Sinonasal Tumors

Sinonasal tumors are rare, diverse, complex lesions with overlapping demographic and clinical features. Malignant tumors are more common, with a grave prognosis, and require biopsy for accurate diagnosis. This article briefly reviews the classification of sinonasal tumors and provides imaging examples and imaging characteristics of each clinically important nasal and paranasal mass lesions. Although there are no true pathognomonic imaging features, it is important for the radiologist to have a broad knowledge of the various CT and MR imaging findings that can help narrow the differential diagnosis and aid in early diagnosis and mapping of tumor for treatment planning.

Intestinal natural killer/T-cell lymphoma presenting as a pancreatic head space-occupying lesion: A case report

BACKGROUND

Intestinal natural killer/T-cell lymphoma (NKTCL) is a rare and aggressive non-Hodgkin’s lymphoma, and its occurrence is closely related to Epstein-Barr virus infection. In addition, the clinical symptoms of NKTCL are not obvious, and the specific pathogenesis is still uncertain. While NKTCL may occur in any segment of the intestinal tract, its distinct location in the periampullary region, which leads clinicians to consider mimics of a pancreatic head mass, should also be addressed. Therefore, there remain huge challenges in the diagnosis and treatment of intestinal NKTCL.

CASE SUMMARY

In this case, we introduce a male who presented to the clinic with edema of both lower limbs, accompanied by diarrhea, and abdominal pain. Endoscopic ultrasound (EUS) showed well-defined homogeneous hypoechoic lesions with abundant blood flow signals and compression signs in the head of the pancreas. Under the guidance of EUS- fine needle biopsy (FNB) with 19 gauge or 22 gauge needles, combined with multicolor flow cytometry immunophenotyping (MFCI) helped us diagnose NKTCL. During treatments, the patient was prescribed the steroid (dexamethasone), methotrexate, ifosfamide, L-asparaginase, and etoposide chemotherapy regimen. Unfortunately, he died of leukopenia and severe septic shock in a local hospital.

CONCLUSION

Clinicians should enhance their understanding of NKTCL. Some key factors, including EUS characteristics, the right choice of FNB needle, and combination with MFCI, are crucial for improving the diagnostic rate and reducing the misdiagnosis rate.

A diagnostic scoring model of ENKTCL in the nose-Waldeyer's ring based on logistic regression: Differential diagnosis from DLBCL

Objective

To establish a logistic regression model based on CT and MRI imaging features and Epstein-Barr (EB) virus nucleic acid to develop a diagnostic score model to differentiate extranodal NK/T nasal type (ENKTCL) from diffuse large B cell lymphoma (DLBCL).

Methods

This study population was obtained from two independent hospitals. A total of 89 patients with ENKTCL (n = 36) or DLBCL (n = 53) from January 2013 to May 2021 were analyzed retrospectively as the training cohort, and 61 patients (ENKTCL=27; DLBCL=34) from Jun 2021 to Dec 2022 were enrolled as the validation cohort. All patients underwent CT/MR enhanced examination and EB virus nucleic acid test within 2 weeks before surgery. Clinical features, imaging features and EB virus nucleic acid results were analyzed. Univariate analyses and multivariate logistic regression analyses were performed to identify independent predictors of ENKTCL and establish a predictive model. Independent predictors were weighted with scores based on regression coefficients. A receiver operating characteristic (ROC) curve was created to determine the diagnostic ability of the predictive model and score model.

Results

We searched for significant clinical characteristics, imaging characteristics and EB virus nucleic acid and constructed the scoring system via multivariate logistic regression and converted regression coefficients to weighted scores. The independent predictors for ENKTCL diagnosis in multivariate logistic regression analysis, including site of disease (nose), edge of lesion (blurred), T2WI (high signal), gyrus like changes, EB virus nucleic acid (positive), and the weighted score of regression coefficient was 2, 3, 4, 3, 4 points. The ROC curves, AUCs and calibration tests were carried out to evaluate the scoring models in both the training cohort and the validation cohort. The AUC of the scoring model in the training cohort were 0.925 (95% CI, 0.906-0.990) and the cutoff point was 5 points. In the validation cohort, the AUC was 0.959 (95% CI, 0.915-1.000) and the cutoff value was 6 points. Four score ranges were as follows: 0-6 points for very low probability of ENKTCL, 7-9 points for low probability; 10-11 points for middle probability; 12-16 points for very high probability.

Conclusion

The diagnostic score model of ENKTCL based on Logistic regression model which combined with imaging features and EB virus nucleic acid. The scoring system was convenient, practical and could significantly improve the diagnostic accuracy of ENKTCL and the differential diagnosis of ENKTCL from DLBCL.

Differentiation between atypical sinonasal non-Hodgkin's lymphoma and inverted papilloma

AIM

To seek additional magnetic resonance imaging (MRI) features to improve the accuracy of differentiation between atypical sinonasal non-Hodgkin's lymphoma (NHL) and inverted papilloma (IP) using conventional MRI and apparent diffusion coefficient (ADC) maps.

MATERIALS AND METHODS

MRI examinations from 44 atypical cases (21 NHLs and 23 IPs) in sinonasal regions were reviewed retrospectively. Imaging features included tumour laterality, extension, T1-weighted imaging (WI)/T2WI signal intensity homogeneity and ratios, enhancement homogeneity and ratios, and ADC_mean.

RESULTS

In cases of NHL, homogeneous signal intensity was often observed on T2WI, which was homogeneous and significantly less enhanced than the turbinate, with lower ADC_mean. Whereas in IPs, heterogeneous signal intensity was seen on T2WI, which was heterogeneous and of comparable enhancement to the turbinate, and higher ADC_mean values were commonly seen. An ADC_mean cut-off point of 1.10 × 10^-3 mm²/s achieved 100% sensitivity, 90% specificity, and 90% accuracy. In addition, special features were observed that support the distinction between the two tumours, including intestinal pattern enhancement in NHL and spot-like appearance on T2WI and enhancement in IP.

CONCLUSIONS

ADC_mean was the most valuable metric for differentiating between the atypical sinonasal NHLs and IPs.