Diagnostic evaluation of mediastinal lesions: Analysis of 144 cases

Is mediastinal fine needle aspiration cytology required or redundant? A single institution-based correlation study with core needle biopsy

INTRODUCTION

Fine Needle Aspiration cytology (FNAC) and core needle biopsy (CNB) are rapid, minimally invasive and useful techniques to evaluate mediastinal lesions.

OBJECTIVES

To compare cytopathology with histopathology of mediastinal lesions and analyse reasons for discordance.

MATERIAL & METHODS

Retrospective analysis was done in a tertiary care centre in North West India over a period of seven and half years from 1stJuly 2016 to 31st December 2023. Only those patients who had undergone FNAC and trucut biopsy of mediastinal masses were included. The cytopathology and histopathology slides were studied to analyse causes of discordance. Sensitivity, specificity, positive and negative predictive values of FNAC were calculated keeping histopathology as gold standard.

RESULTS

Out of 57 cases analysed, eight cases were non diagnostic on cytology. Cytology could effectively classify a lesion as non neoplastic (7) or neoplastic (42). For further subtyping, histopathology and Immunohistochemistry (IHC) were required. Out of 27 cases of cytological - histopathological discordance, 8 cases had sampling error, 15 cases had limited concordance where FNAC could predict possibility of tumor and 4 cases were discordant where subtyping of malignancy varied on CNB. Sensitivity of FNAC to predict definite diagnosis was 90.2 %, specificity was 50 %, positive predictive value of FNAC to give a definite diagnosis was 93.9 %, negative predictive value was 37.5 %.

CONCLUSION

Evaluation of mediastinal masses requires combination of cytology, histopathology and ancillary techniques like IHC. FNAC and CNB are complementary modalities and both are essential for rapid, accurate and comprehensive diagnosis.

Thymoma in multiple endocrine neoplasia type 1: a case report and systematic review

BACKGROUND

Multiple endocrine neoplasia type 1 (MEN1) is a rare syndrome that combines endocrine and non-endocrine tumors. Thymic neuroendocrine tumors are uncommon components that predict poor prognosis in patients with MEN1. We aimed to summarize the clinical characteristics of thymoma in MEN1 by reviewing the current reports from the literature.

METHODS

A patient with multiple endocrine neoplasia type 1 (parathyroid hyperplasia, pituitary adenoma, and insulinoma) was found to have a 2 × 1.5 cm thymic mass during long-term follow-up. Thoracoscope surgery was performed, and a histopathology examination revealed WHO Type B3 thymoma. A pathogenic mutation of c.783 + 1G > A in the MEN1 gene was identified. We further searched PubMed and EMBASE for thymoma in association with MEN1.

RESULTS

A comprehensive overview of the literature concerning characteristics of MEN1-related thymoma was summarized. Clinical characteristics and differences between thymoma and thymic carcinoid are highlighted.

CONCLUSIONS

Besides carcinoid, other tumors, including thymoma, need to be identified for thymic space-occupying lesions in MEN1 patients. The impact of thymoma on the long-term prognosis of MEN1 patients needs further investigation.

GIANT MEDIASTINAL PARATHYROID ADENOMAS AND MULTIPLE ENDOCRINE NEOPLASIA TYPE 1: A DIAGNOSTIC CONUNDRUM

CONTEXT

Giant parathyroid adenoma (GPA) is a rare entity that is rarer with Multiple endocrine neoplasia type 1 (MEN1) syndrome.

OBJECTIVES

Describe the clinical presentation, diagnostic difficulties, and management strategy for GPA in MEN1.

METHODS

We searched Pubmed, SCOPUS and EMBASE for GPA in MEN1 for GPA in association with MEN1. Hereby, we describe index case of largest ever reported GPA.

RESULTS

We identified 7 cases of GPA reported till date in association with MEN1. The mean adenoma weight was 7.1 gram. The index case is largest-ever reported GPA (weight 97 gram) in MEN1 presenting with compressive symptoms and mediastinal mass. Incidentally, she was found to have hypercalcemia with increased parathyroid hormone, suggesting primary hyperparathyroidism. The possibilities of an ectopic parathyroid tumor and thymic carcinoid were considered. She also had acromegaloid features, and was found to have a sellar tumor. Subsequently, MENIN gene mutation was identified confirming MEN1 syndrome. Patient underwent trans-sternal excision of the mass weighing 97 grams and confirmed as parathyroid adenoma on histopathologic examination.

CONCLUSION

Despite rarity of ectopic mediastinal parathyroid tumors, calcium profile should be considered as part of work-up of considering varied etiologies of anterior mediastinal mass.

Ultrasound-Guided Transthoracic Mediastinal Biopsy: A Safe Technique for Tissue Diagnosis in Middle- and Low-Income Countries

Background and objectives

The high cost of video-assisted transthoracic procedures precludes their use in the diagnostics of mediastinal masses in low- and middle-income countries (LMICs). This study aims to assess the technical success rate and diagnostic yield of ultrasound-guided transthoracic mediastinal biopsies at a tertiary care hospital.

Methods

This descriptive cross-sectional study was conducted in patients presenting with mediastinal masses referred to radiology services at Dr. Ziauddin University Hospital. Karachi, Pakistan. Ultrasonography was performed using Toshiba Xario 200 & Aplio 500 using convex and linear probes accordingly. Biopsy was performed using a combination of 18G semiautomatic trucut and 17G co-axial needles. Complications and overall diagnostic yields were determined.

Results

In all 70 patients referred, the procedure was completed successfully with an overall procedural yield of 95.7%. Inconclusive biopsies due to inadequate specimen were seen in two (4.2%) patients. No post-procedure major complication or mortality was observed. Minor complications were seen in three (4.2%) out of 70, including hematoma (<3 cm) in one patient and small pneumomediastinum in two patients.

Conclusion

Ultrasound-guided transthoracic mediastinal biopsy may be the pragmatic technique of choice in LMICs for the diagnosis of mediastinal masses as they provide real-time visualization and is cost-effective and safe.

Presenting Symptomatology of Mediastinal Masses and Its Effect on Surgical Outcomes

OBJECTIVE

Mediastinal masses are commonly encountered by the thoracic surgeon. Few studies have reported on the frequency and characteristics of symptoms at presentation. The primary objective of this study is to determine how often patients present with symptoms from a mediastinal mass. The secondary objective is to determine if the presence of symptoms has an effect on outcomes after surgery.

METHODS

A retrospective review of an institutional database was performed. All patients who underwent surgical resection of a mediastinal mass from 2013 to 2019 were included in the analysis. Medical records were reviewed for the presence or absence of symptoms preoperatively, and these cohorts were compared. Multivariable analysis was performed, adjusting for clinical variables to assess for differences between these cohorts.

RESULTS

70 patients underwent surgery for a mediastinal mass. The average age was 49.2 years, and 46 patients (65.7%) presented with symptoms. There were no significant differences in demographics between the symptomatic and asymptomatic groups. The most common symptom was dyspnea in 18 patients (22%), followed by chest pain (15 patients, 19%) and dysphagia (8 patients, 10%). When comparing symptomatic and asymptomatic patients, symptomatic patients had a larger tumor size (5.8 cm vs 3.8 cm, P = .04) and a longer length of stay (2.0 days vs 1.2 days, P = .02).

CONCLUSIONS

The majority of patients with mediastinal masses present with symptoms, with the most common symptom being dyspnea. Symptomatic patients are more likely to have a larger tumor and tend to have a longer length of hospital stay postoperatively compared to asymptomatic patients.

Fine-needle aspiration cytology of mediastinal masses: An institutional experience

Introduction:

Mediastinal masses are uncommon in clinical practice. Fine-needle aspiration cytology (FNAC) is an important and useful investigation and is considered next to imaging in the diagnosis of mediastinal lesions.

Aim:

To analyze the mediastinal masses diagnosed on FNAC.

Materials and Methods:

We retrospectively retrieved twenty-five cases, which underwent FNAC under ultrasound or computed tomography (CT) guidance for mediastinal masses, over a period of 4 years. Histopathological correlations were done in cases wherever available.

Results:

Among twenty-five cases, which were diagnosed through FNAC, eighteen were males and seven were females with age ranging from 6 to 85 years. Ultrasonography (USG)-guided FNAC was performed in three patients, while CT-guided FNAC was performed in twenty-two patients. Out of twenty-five cases, seventeen cases were malignant, six were benign, and two cases were inadequate. FNAC was useful in the diagnosis of 83.3% of cases. Biopsy and/or cell block correlations were available in fourteen cases. In the malignant category, mediastinal invasion by either squamous cell carcinoma or adenocarcinoma constituted the highest number with eight (47%) out of seventeen cases. Among the nonneoplastic conditions, nonspecific inflammation was the most common cause with two cases (8%) out of total cases followed by one case each of tuberculosis, schwannoma, thymoma, and cystic lesion.

Conclusion:

USG or CT-guided FNAC is a safe, minimally invasive, and cost-effective procedure, which can provide a precise diagnosis in the mediastinal masses, and may obviate the need for an invasive surgical approach.

An overview on the differential diagnostics of tumors of the anterior-superior mediastinum: the pathologist's perspective

The thymus is the main organ in the (anterior) (pre-vascular) mediastinum, playing a central role in the maintenance of both cellular and humoral immunity. The function of the thymus has been long underlooked due to its involution starting during young adulthood and unawareness regarding its immunological function. A variety of primary tumors and inflammatory/reactive/disreactive processes occur in the mediastinum and may involve the anterior-superior compartment and the thymus. Maldevelopment processes also take place in the pre-vascular compartment mediastinum. Although infective diseases do not currently represent the main processes in western countries, they may represent a diagnostic challenge in developing countries. The purpose of this review is to provide a short overview of the main thymic cellular components, their tumors, pseudotumors, in order to provide insights into their clinical setting and the features which assist pathologists in their differential diagnosis (DD). Specific differential diagnostic points are provided, both for "solid" tumors as well as for haematological malignancies, together with a morphological overview of cases of concern that occur in the anterior mediastinum. The main immunohistochemical characteristics of neoplastic/non-neoplastic pathology and updated specific references are also provided.

Diagnostic accuracy of multidetector computed tomography scan in mediastinal masses assuming histopathological findings as gold standard

Purpose

Aim of the study was to: 1) present MDCT characteristics of different mediastinal mass lesions, 2) estimate proportion of benign and malignant mediastinal mass lesions based on MDCT findings, and 3) find out the diagnostic accuracy with sensitivity, specificity, positive predictive value, and negative predictive value of MDCT in mediastinal mass lesions assuming histopathology as gold standard.

Material and methods

This study was an analysis of 60 patients who underwent MDCT scan for characterisation of mediastinal mass lesion, and subsequently imaging findings were verified with pathological diagnosis.

Results

Out of 60 patients 65% were malignant and 35% were benign. Metastatic carcinoma was the leading diagnosis. Sensitivity of MDCT in this study came out to be 94%, specificity is 90%, with a positive predictive value of 94% and negative predictive value of 90% with diagnostic accuracy of 93%.

Conclusions

Mediastinal mass lesion can be accurately diagnosed with MDCT which is a non-invasive and easily available modality requiring clinical data for accurate diagnosis and management. Co-relation of MDCT findings with other imaging findings is complex and requires adequate clinical data for optimum diagnostic confidence.