Update on the potential significance of psammoma bodies in lung adenocarcinoma from a modern perspective

The clinicopathologic significance of psammoma bodies in cytology specimens: A series of 78 cases

BACKGROUND

Currently the clinicopathologic significance of psammoma bodies in cytology specimens are not completely understood, including types of cytology specimens and pathologic conditions frequently associated with this unique cytologic feature. In this study, we undertook a retrospective approach to review the specimen types, cytology preparations, patient characteristics, organs or tissues involved and differential diagnoses in cytology specimens with the finding of psammoma bodies.

METHODS

Cytology cases with the finding of psammoma bodies from January 2004 to December 2022 were retrieved from our institution's pathology databases, and their clinicopathological features were reviewed.

RESULTS

A total of 78 cytology specimens with the finding of psammoma bodies were recorded in our CoPath system. The mean age at diagnosis was 59 years. The patient group showed female gender predominancy (90%). FNA specimens comprised about 38.5% of total cases. Other common specimen types were body cavity fluids (38.5%), including pleural effusion and peritoneal fluid, and about 20.5% of the cases were pelvic washing performed during gynecologic surgeries. Most cytology cases with psammoma bodies had a malignant diagnosis (69%). About 18% of the cases were in the indeterminate diagnostic categories, with 12% suspicious for malignancy and 6% of the cases with atypical cells. About 5% of cases were placed in the neoplastic category, while 8% of cases were negative for malignancy. About 79% of peritoneal cytology with psammoma bodies were neoplastic and mostly gynecologic tumors. Pleural fluids with psammoma bodies were very likely to be malignant and involved by serous carcinoma (15 of 16 cases, 94%). Papillary thyroid carcinoma was the second most common malignancy in our series, present in about 53% of thyroid cytologies with the finding of psammoma bodies.

CONCLUSION

Our study showed that psammoma bodies in cytology preparations were more often associated with malignancies in our study of 78 cytology specimens (69%). The most sampled location in our study was peritoneal cavity, followed by pleural cavity, thyroid, lymph nodes, neck masses, and omentum. The clinicopathologic value of psammoma bodies in predicting malignancy varies depending on locations and specimen types.

ROS1-Rearranged Lung Cancer With Extensive Calcification on Computed Tomography: A Case Report

Although calcified lung cancers are occasionally observed, they are quite rare. We report a case of extensively calcified lung adenocarcinoma with ROS1 fusions. A 57-year-old Japanese woman was initially diagnosed with adenocarcinoma based on aspiration cytology of an enlarged left supraclavicular fossa lymph node at the Department of Otorhinolaryngology at our institution. Subsequent chest imaging suggested primary lung cancer, leading to a referral to the Department of Respiratory Medicine. Computed tomography of the chest revealed a nodular shadow in the right S5 lobe and enlarged mediastinal lymph nodes with extensive calcification. A bronchoscopy with transbronchial lung biopsy of the right S5 nodule confirmed the diagnosis of adenocarcinoma. The biopsy specimen was analyzed using the AmoyDx® Pan Lung Cancer PCR Panel, which detected ROS1 fusions.

Intrathoracic Lymph Node Microcalcifications are Associated With a High Prevalence of Malignancy and Anaplastic Lymphoma Kinase Rearrangement: The "Calce" Study

BACKGROUND

Microcalcifications are acknowledged as a malignancy risk factor in multiple cancers. However, the prevalence and association of intrathoracic lymph node (ILN) calcifications with malignancy remain unexplored.

METHODS

In this cross-sectional study, we enrolled patients with known/suspected malignancy and an indication for endosonography for diagnosis or ILN staging. We assessed the prevalence and pattern of calcified ILNs and the prevalence of malignancy in ILNs with and without calcifications. In addition, we evaluated the genomic profile and PD-L1 expression in lung cancer patients, stratifying them based on the presence or absence of ILN calcifications.

RESULTS

A total of 571 ILNs were sampled in 352 patients. Calcifications were detected in 85 (24.1%) patients and in 94 (16.5%) ILNs, with microcalcifications (78/94, 83%) being the predominant type. Compared with ILNs without calcifications (214/477, 44.9%), the prevalence of malignancy was higher in ILNs with microcalcifications (73/78, 93.6%; P<0.0001) but not in those with macrocalcifications (7/16, 43.7%; P=0.93). In patients with lung cancer, the high prevalence of metastatic involvement in ILNs displaying microcalcifications was independent of lymph node size (< or >1 cm) and the clinical stage (advanced disease; cN2/N3 disease; cN0/N1 disease). The anaplastic lymphoma kinase (ALK) rearrangement was significantly more prevalent in patients with than in those without calcified ILNs (17.4% vs. 1.7%, P<0.001), and all of them exhibited microcalcifications.

CONCLUSION

ILN microcalcifications are common in patients undergoing endosonography for suspected malignancy, and they are associated with a high prevalence of metastatic involvement and ALK rearrangement.

Psammomatous calcifications in thyroid oncocytic (Hürthle cell) follicular tumors

Concentric calcifications, also known as psammoma bodies, are a relatively frequent finding in certain types of tumors, particularly papillary thyroid carcinoma (PTC). In the thyroid, they have been assigned a significant role in the diagnosis of PTC and in distinguishing between these tumors and other types of thyroid neoplasms. Concentric calcifications have also less commonly been noted in other processes in the thyroid, such as in tumors characterized by cells containing abundant oxyphilic cytoplasm (i.e., Hürthle cells). We have studied 12 patients with oncocytic thyroid follicular tumors that contained scattered psammomatous calcifications that led to difficulties in diagnosis. The patients were 9 women and 3 men, aged 34 to 63 years. 10 cases corresponded to benign, non-invasive oncocytic tumors and 2 cases were minimally invasive follicular carcinomas of oncocytic (so called Hürthle cell) type. The psammomatous calcifications were randomly scattered throughout the lesions and were present as a focal, incidental finding in 8 cases and were diffuse in 4 cases. They were composed of concentrically laminated deposits of dense basophilic material closely resembling psammoma bodies, often associated with more homogeneous deposits of lightly eosinophilic material without concentric lamination that were interpreted as precipitated thyroglobulin. Seven patients with clinical follow-up, including one with minimally invasive carcinoma, were alive and well between 5 and 12 years after diagnosis. Concentric laminated calcifications may be encountered in oncocytic (Hürthle cell) follicular tumors and should not be interpreted as indicative of PTC in the context of oncocytic neoplasms of the thyroid.

Remarkable Differences in Calcification between the Primary Tumor and Metastatic Lymph Nodes in a Patient with ALK-Positive Non-Small-Cell Lung Cancer

Calcified bilateral mediastinal lymph nodes are not common in malignant tumors. A 51-year-old woman presented to our hospital with a 20 mm nodule in the lower left lobe of the lung and extensive calcification in the bilateral mediastinal lymph nodes. Computed tomography indicated no calcification of the primary lesion. Immunohistochemical staining and fluorescent in situ hybridization detected an anaplastic lymphoma kinase (ALK) fusion. Treatment with alectinib, an ALK inhibitor, led to a significant reduction in tumor size and calcification in the lymph nodes. This case shows that different degrees of calcification can be associated with malignant tumors and may be reversible in some cases.

Extensive calcification in adenocarcinoma of the lung: A case report

Calcification in lung nodules usually indicates a benign lesion. Here, we report the case of a 59‐year‐old male patient with a well defined 30 mm calcified nodule in his right upper lung lobe and calcified mediastinal lymph nodes. The mass was diagnosed as adenocarcinoma by transbronchial biopsy. He received systemic chemotherapy, followed by lobectomy and mediastinal lymph node dissection. During surgery, the lymph nodes were tightly adherent to the superior vena cava with invasion of the vascular wall. Pathological diagnosis confirmed acinar adenocarcinoma and psammoma bodies (PBs). Immunohistochemical analysis revealed tumor cells positive for parathyroid hormone‐related proteins 1 and 2. Calcification of primary lung adenocarcinoma is rare. We report a calcified lesion where the secretion of parathyroid hormone by the tumor may have caused the accumulation of PBs. Calcification of metastatic lymph nodes may increase the risk of adhesion, requiring care during surgery.

Key points

Significant findings of the study

Lung adenocarcinoma with extensive calcification in primary and metastatic lymph node lesions is rare and the mechanism involved is poorly understood. Of significance, calcification in our case was related to parathyroid hormone‐related proteins 1 and 2 secreted by the tumor.

What this study adds

This study suggests the potential role of parathyroid hormone‐related proteins in lung tumor calcification. The implications for clinicians are that calcified metastatic lymph nodes and tumors might be tightly fused to tissues. Therefore, surgery should be conducted with care.

Pulmonary adenocarcinoma with psammoma bodies is associated with a specific endobronchial ultrasound pattern and a high prevalence of actionable driver mutations

INTRODUCTION

Pulmonary adenocarcinoma with psammoma bodies (PAPBs) is a rare histological variant whose association with a high prevalence of targetable mutations has been suggested by scant literature reports describing small series. We aim to describe the endobronchial ultrasound (EBUS) pattern and the molecular profile by next-generation sequencing of an Italian series of patients with PAPBs.

MATERIAL AND METHODS

Over a 8-year period (2012-2019), we identified 15 patients with a very uncommon endobronchial ultrasound (EBUS) heterogeneity pattern characterized by the presence of multiple to countless, punctate non-shadowing foci ("starry sky" sign) which were not evident at CT and corresponded to psammoma bodies at pathological examination. The clinical, radiological, pathological and molecular findings of these patients were retrieved and analyzed.

RESULTS

Pathological examination of the EBUS-TBNA specimens revealed malignancy (12 pulmonary adenocarcinoma, 2 breast carcinoma, 1 colonic carcinoma) and showed the presence of psammoma bodies in all of the 15 patients with the starry sky sign. Among the 12 patients with pulmonary adenocarcinoma with psammoma bodies, female sex (8/12, 66.7 %) and never-smoking habit (6/12, 50 %) were prevalent. Molecular tumor profiling using the Oncomine™ Focus DNA and RNA fusion panels was successfully performed in 11/12 patients and revealed 10 genetic alterations (BRAF mutation, 4; EGFR mutation, 2; ALK rearrangement, RET rearrangement, PIK3CA mutation, CDK4 amplification 1) in 7 patients (63.6 %).

CONCLUSION

The present series suggests that pulmonary adenocarcinoma with psammoma bodies is associated with a readily identifiable EBUS pattern and with a high prevalence of different, often uncommon and actionable, driver mutations.

Papillary lung adenocarcinoma with psammomatous calcifications

We present the case of a 71 y/o man with chronic obstructive pulmonary disease (COPD) who presented with 3 weeks of cough, phlegm, fever, and failed outpatient antibiotic therapy for pneumonia. CT of the chest showed unilateral interstitial changes and bronchoscopic biopsies demonstrated primary lung papillary adenocarcinoma and extensive concentric psammomatous calcifications.