Mediastinal Lymphoproliferative Disorders

Primary Refractory Discordant Diffuse Large B-Cell and Classical Hodgkin Lymphoma

Discordant lymphomas are defined as two or more distinct pathological lymphomas occurring in the same patient. Due to the rarity of discordant lymphomas, which is due in large part to the difficulty in establishing the diagnosis, the literature is limited to small case series and case reports. Consequently, guidelines on therapeutic strategies are lacking. This article presented a case of primary refractory discordant large B-cell lymphoma and classic Hodgkin lymphoma in a young man based on cervical node and mediastinal mass biopsy, respectively. This case illustrates the difficulty in establishing the diagnosis, which ultimately warranted a high index of clinical suspicion and pursuit of multiple sequential biopsies, as well as a novel treatment strategy using an immune checkpoint inhibitor.

Therapeutic Decision Making in Prevascular Mediastinal Tumors Using CT Radiomics and Clinical Features: Upfront Surgery or Pretreatment Needle Biopsy?

The study aimed to develop machine learning (ML) classification models for differentiating patients who needed direct surgery from patients who needed core needle biopsy among patients with prevascular mediastinal tumor (PMT). Patients with PMT who received a contrast-enhanced computed tomography (CECT) scan and initial management for PMT between January 2010 and December 2020 were included in this retrospective study. Fourteen ML algorithms were used to construct candidate classification models via the voting ensemble approach, based on preoperative clinical data and radiomic features extracted from the CECT. The classification accuracy of clinical diagnosis was 86.1%. The first ensemble learning model was built by randomly choosing seven ML models from a set of fourteen ML models and had a classification accuracy of 88.0% (95% CI = 85.8 to 90.3%). The second ensemble learning model was the combination of five ML models, including NeuralNetFastAI, NeuralNetTorch, RandomForest with Entropy, RandomForest with Gini, and XGBoost, and had a classification accuracy of 90.4% (95% CI = 87.9 to 93.0%), which significantly outperformed clinical diagnosis (p < 0.05). Due to the superior performance, the voting ensemble learning clinical-radiomic classification model may be used as a clinical decision support system to facilitate the selection of the initial management of PMT.

Thymic hyperplasia with lymphoepithelial sialadenitis (LESA)-like features: a case report and literature review

BACKGROUND

Thymic hyperplasia with lymphoepithelial sialadenitis-like features (LESA-like TH) is a rare form of thymic hyperplasia, characterized by a prominent expansion of the thymic medulla containing hyperplastic lymphoid follicles with germinal centers, while an almost total absence of thymic cortex. Since the first report in 2012, only a few cases of LESA-like TH have been reported in the literature to date. Due to the rarity of LESA-like TH and the tumor-like morphology, it is easy to be misdiagnosed as other common diseases of the thymus in routine practice, such as thymoma and lymphoma.

CASE PRESENTATION

Herein, we present a case report of a 52-year-old Chinese female patient with LESA-like TH, without any discomforting symptoms. Computer-tomography imaging revealed a cystic solid mass in the anterior mediastinum, with well-defined boundaries and multiple internal septa. Histologically, prominent features were florid lymphoid follicles containing germinal centers, as well as hyperplasia of thymic epithelial cells and proliferation of Hassall bodies. However, the thymic cortex rich in immature T cells was almost completely absent. Furthermore, mature plasma cells, lymphoepithelial lesions, and cholesterol clefts were frequently seen.

CONCLUSION

We made a diagnosis of LESA-like TH and performed a literature review to better understand the clinicopathological features of LESA-like TH and reduce misdiagnosis.

The Utility of Fine Needle Aspiration (FNA) Biopsy in the Diagnosis of Mediastinal Lesions

Fine needle aspiration is a minimally invasive, low-morbidity, and cost-efficient technique for the sampling of mediastinal lesions. Additionally, ancillary testing on FNA samples can be used for the refinement of diagnoses and for treatment-related purposes (flow cytometry, cytogenetics, immunohistochemistry, and molecular diagnostics). Mediastinal lesions, however, can show a variety of lineages and morphologic features, giving rise to diagnostic dilemmas. As a result, the differential diagnosis can vary widely and becomes especially challenging due to the smaller sample size on FNA and the variability in component sampling. For appropriate patient management and to determine the correct treatment strategies, accurate pathologic diagnoses are paramount. In this review, we present the cytomorphologic features together with the immunophenotypic findings of mediastinal lesions, with emphasis on the diagnostic challenges and pitfalls in FNA cytology samples, including smears and cell block sections.

Patients and Families' Participation in Multidisciplinary Tumor Conferences Improves Patient and Family-Focused Cancer Care: Lessons Learned From a Debate on the Role of Radiation Therapy in Primary Mediastinal Non-Hodgkin Lymphoma

Incorporation of patients' preferences often leads to improved outcomes when included in the multidisciplinary tumor conference/board (MTC). However, patients' wishes are not included or considered in the MTC decision-making. We need better strategies and approaches for patient-inclusive, shared decision-making. When finding ourselves at a crossroads regarding the next step in a patient's treatment, we saw a unique opportunity for an MTC with the patient and her husband in attendance. The results of a full literature review regarding the role of consolidative radiation therapy (RT) in a patient with primary (thymic) B-cell lymphoma after completion of chemotherapy and fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT) scan with a Deauville score of 4 were presented in a creative, engaging debate-style forum with visual aids. The patient and her husband were able to follow the discussion and, in the end, a consensus recommendation, heavily focused on the patient's preferences, was offered and adopted, which ultimately resulted in the avoidance of excess treatment and likely improved her long-term quality of life outcome. These collaborative and innovative interactions benefit not only our patients but enrich our lives too as healthcare providers and strengthen us as a cancer care team in terms of understanding diversity in decision-making processes.

Coexistence of primary mediastinal MALT lymphoma and multiple myeloma like POEMS syndrome: A case report and literature review

RATIONALE

The coexistence of the extranidal marginal zone lymphoma (MZL) of mucosa-associated lymphoid tissue (MALT) and multiple myeloma (MM) is an exceedingly rare situation. The rare situation precludes any evidence-based guidelines for MZL or MM.

PATIENT CONCERNS AND DIAGNOSES

We presented a unique case of the coexistence of primary mediastinal MALT lymphoma and MM like polyneuropathy, organomegaly, endocrinopathy, M-protein, skin syndrome.

INTERVENTIONS AND OUTCOMES

The patient was first diagnosed with polyneuropathy, organomegaly, endocrinopathy, M-protein, skin syndrome in the department of neurology, then MM in the department of hematology, and the mediastinal MALT simultaneously coexisting with MM was found by biopsy in the department of thoracic surgery. The patient received combination therapy with rituximab and bortezomib followed by lenalidomide maintenance. To understand MZL lymphoma with plasmacytic differentiation better, we analyzed cases of MZL lymphomas with plasma cell neoplasms. Most of these cases were MZL lymphomas with light chain-restricted plasmacytic differentiation. The lymphomas relapsed with plasma cell neoplasms or transformed into plasma cell neoplasms after anti-lymphoma therapy.

LESSONS

The case demonstrated clinical complexity and the importance of the detailed assessment. The case and literature review demonstrated the value of detecting light chain-restricted plasmacytic differentiation for the treatment of MZL lymphoma with rituximab plus lenalidomide or bortezomib.

Novel intraoperative near-infrared imaging strategy to identify abnormalities in the anterior mediastinum

Thoracic surgeons are frequently asked to biopsy suspicious tissues in the anterior mediastinum to discriminate between a reactive versus malignant pathology such as lymph nodes. The most common benign cause of a mediastinal lymph node is a reactive lymph node from a prior infection or inflammatory process such as post-COVID or granulomatous disease. The most common malignant cause is a lymphoproliferative disorder but also metastatic disease from neck, breast and other regional cancers. Biopsies in this location are challenging because they are far from the trachea and the sternum is a barrier to most diagnostic procedures. Thus, a surgical biopsy is frequently required and a common procedure for Thoracic surgeons. Technically, identifying these lesions can be challenging, particularly for small lesions or those in patients with high body mass index. In order to improve contrast between diseased tissue in the anterior mediastinum and surrounding adipose tissue, we have been studying near-infrared imaging during surgery using indocyanine green (ICG) to give contrast to the abnormal tissues and to avoid an unnecessary extended resection. We developed a modified technique to give ICG to a patient during a biopsy in the anterior mediastinum to specifically highlight abnormal tissues. As a proof-of-principle, we present a case of a young woman with a suspicious 2 cm mediastinal lymph node that required surgical biopsy.

Incidence, mortality, and survival analyses of patients with thymic lymphoma

Objectives

To explore the clinical and prognostic characteristics of thymic lymphoma and the effects of current treatments on the prognosis.

Methods

Patients diagnosed as primary thymic lymphoma between 1975 and 2018 from the nine states of the US were identified, including Atlanta, Connecticut, Detroit, Hawaii, Iowa, New Mexico, San Francisco-Oakland, Seattle–Puget Sound, and Utah. Incidence and mortality rates were analyzed using SEER*Stat 8.3.9 software. Univariate and multivariate Cox regressions were performed to identify prognostic factors. The Kaplan–Meier curve and log-rank test were used to compare overall survival (OS) among different treatments.

Results

A total of 233 patients diagnosed as thymic lymphoma were identified, and eight of them were lost to follow-up or died upon diagnosis. The incidence of thymic lymphoma was 2.032 per ten million (95% CI: 1.777–2.312), and the mortality rate was 0.649 per ten million (95% CI: 0.508–0.817). Among the 225 patients with definite follow-up, 98 were males and 127 were females, with a median age of 33 years. The Cox regression results showed that age and pathological type were independent risk prognostic factors. The 5-, 10-, and 20-year OS were 80.0%, 77.5%, and 70.9%, respectively. For Ann Arbor stage I and II patients, there was no significant difference between the surgical group (N = 78) and the non-operative group (N = 65; P = 0.270). The radiotherapy group (N = 79) had better OS than the non-radiotherapy group (N = 64) in the first 25 years, and the prognosis in the later years was not significantly different (P = 0.051). The chemotherapy group (N = 37) had a significantly better prognosis than the non-chemotherapy group (N = 37; P = 0.020). Patients who received postoperative radiotherapy (N = 45) or who only received radiotherapy (N = 34) seemed to have better OS than that of patients who only received surgery (N = 33), although the difference was not significant (P = 0.063).

Conclusions

Age and pathological type were independent prognostic factors for thymic lymphoma. Surgical treatment had limited effects on OS, while both radiotherapy and chemotherapy could significantly improve the survival outcome.

An MRI-Based Clinical-Perfusion Model Predicts Pathological Subtypes of Prevascular Mediastinal Tumors

This study aimed to build machine learning prediction models for predicting pathological subtypes of prevascular mediastinal tumors (PMTs). The candidate predictors were clinical variables and dynamic contrast–enhanced MRI (DCE-MRI)–derived perfusion parameters. The clinical data and preoperative DCE–MRI images of 62 PMT patients, including 17 patients with lymphoma, 31 with thymoma, and 14 with thymic carcinoma, were retrospectively analyzed. Six perfusion parameters were calculated as candidate predictors. Univariate receiver-operating-characteristic curve analysis was performed to evaluate the performance of the prediction models. A predictive model was built based on multi-class classification, which detected lymphoma, thymoma, and thymic carcinoma with sensitivity of 52.9%, 74.2%, and 92.8%, respectively. In addition, two predictive models were built based on binary classification for distinguishing Hodgkin from non-Hodgkin lymphoma and for distinguishing invasive from noninvasive thymoma, with sensitivity of 75% and 71.4%, respectively. In addition to two perfusion parameters (efflux rate constant from tissue extravascular extracellular space into the blood plasma, and extravascular extracellular space volume per unit volume of tissue), age and tumor volume were also essential parameters for predicting PMT subtypes. In conclusion, our machine learning–based predictive model, constructed with clinical data and perfusion parameters, may represent a useful tool for differential diagnosis of PMT subtypes.