Immune-checkpoint inhibitors have profoundly changed cancer treatment, improving the prognosis of many oncologic patients. However, despite the good efficacy of these drugs, their mechanism of action, which involves the activation of the immune system, can lead to immune-related adverse events, which may affect almost all organs. Pulmonary adverse events are relatively common, and potentially life-threatening complications may occur. The diagnosis is challenging due to the wide and non-specific spectrum of clinical and radiological manifestations. The role of the radiologist is to recognize and diagnose pulmonary immune-related adverse events, possibly even in the early stages, to estimate their extent and guide patients\' management.

Sarcoid Like Reaction (SLR) is a localized non-caseating epithelioid granulomatous reaction seen secondary to certain immunotherapies and malignancies. Invasive melanoma, while being associated with onset of sarcoidosis, has not shown to directly induce SLR in the literature. We present the case of a 68-year-old male with malignant melanoma, who was found to have SLR prior to starting immunotherapy, which worsened while on pembrolizumab. This case highlights the challenge of distinguishing between drug-induced SLR and melanoma-induced SLR, and the implications in terms of management.

UNASSIGNED: Coronavirus disease (COVID-19)-associated acute pericarditis has recently received much attention owing to its high frequency associated with pericardial tamponade (PT), showing unfavorable prognosis. However, early diagnosis and treatment remain challenging in cases of non-specific signs and symptoms.
UNASSIGNED: A 64-year-old man was admitted to our hospital for acute osteomyelitis of the toes and was properly treated with antimicrobial agents. Three days after admission, the patient developed mild COVID-19 without pneumonia, for which early anti-COVID-19 agents were initiated. Nevertheless, the patient developed hemorrhagic PT due to acute pericarditis 2 weeks later, which was confirmed by cardiac magnetic resonance, requiring an urgent pericardiocentesis. Although cytological analysis of the hemorrhagic pericardial fluid strongly suggested adenocarcinoma, the atypical cells were eventually proven to be mesothelial cells with reactive atypia. Furthermore, lymph nodes swelling with abnormal 2-[18F]-fluoro-2-deoxy-D-glucose accumulation on imaging were suggestive of malignancy. However, biopsy examination revealed multiple non-caseating granulomas in the lymph node, unlikely due to malignancy. Eventually, the temporal association of the preceding COVID-19 with the occurrence of subacute PT without other identifiable cause led to a final diagnosis of COVID-19-associated acute pericarditis. With anti-inflammatory and corticosteroids treatment, the patient\'s symptoms involving the pericardial structure and function were completely resolved along with improvements in size of the affected lymphadenopathies.
UNASSIGNED: We encountered a unique case of COVID-19-associated acute pericarditis exhibiting hemorrhagic PT. This case underscores the residual risk of delayed pericardial involvement even in patients with mild COVID-19 who receive early treatment, and the recognition that COVID-19 may cause various cytomorphological and histological features. Additionally, the importance of considering this rare entity as a cause of hemorrhagic pericardial effusions should be highlighted.

Sarcoid-like granulomatous inflammation (SLGI) is defined as the development of non-necrotizing epithelioid granulomas in patients who do not meet the criteria for systemic sarcoidosis. Its occurrence is known to be linked to diverse conditions, including malignancies, infections, the use of certain drugs and inorganic substances. To the best of our knowledge, the available literature to date lacks any description regarding SLGI in a paraganglioma. The present study describes the first case of SLGI in a carotid body paraganglioma (CBP). A 54-year-old female patient presented with anterior neck swelling for 27 years without any other symptoms. An ultrasonography revealed a multinodular goiter with retrosternal extension and a solid lesion on the right side of the neck measuring 40x30x22 mm, which was suggestive of a CBP. The patient underwent a total thyroidectomy, and the right-side cervical mass was resected via another longitudinal incision. A histopathological examination of the thyroid specimen revealed findings of a multinodular goiter. Sections from the right-side cervical mass confirmed the diagnosis of CBP accompanied by multiple, well-formed, small-medium sized, non-necrotizing epithelioid granulomas associated with multinucleated giant cells, indicative of SLGI. Non-necrotizing epithelioid cell granulomas (as with SLGIs), identical to those observed in sarcoidosis, may rarely be observed in patients who do not meet the criteria of systemic sarcoidosis; however, they have been observed in association with various neoplasms. It is thus crucial to distinguish them from actual sarcoidosis, as misdiagnoses may lead to severe consequences. The presence of SLGIs accompanying a paraganglioma is an extremely rare phenomenon. Due to this, it is difficult to conclude if it confers a better prognosis or not.

BACKGROUND: The drug-induced sarcoidosis-like reaction (DISR) is a condition clinically and pathologically similar to sarcoidosis but is induced by certain drugs. A few cases of DISR associated with the use of TNF-α antagonists have been reported in the literature.
METHODS: A 49-year-old female patient with a diagnosis of Crohn\'s Disease under treatment with adalimumab presented with a 2-month-long ulcerated swelling in the left lower fornix. Histological analysis of the biopsy specimen revealed multiple non-caseating granulomas multinucleated cells and epithelioid macrophages surrounded by lymphocytes. The lesion is under symptomatic control with a topical corticosteroid, and the patient is being monitored for manifestation in other organs and systems.
CONCLUSIONS: Lesions of DISR may occur isolated in the oral mucosa. Therefore, this complication must be considered in the differential diagnosis of oral granulomatous lesions in patients under treatment with anti-TNF-α drugs.

BACKGROUND: Patients with breast cancer present with lymphadenopathy involving non-caseating epithelioid cell granulomas in the mediastinum or axilla, referred to as sarcoidosis or sarcoid-like reactions (SLRs). However, sarcoidosis/SLRs prevalence and clinical presentation remain unclear. This study aimed to determine the frequency and clinical presentation of sarcoidosis/SLRs among postoperative patients with breast cancer.
METHODS: Among all patients who underwent surgery for early-stage breast cancer at St. Luke\'s International Hospital in Japan between 2010 and 2021, those who subsequently developed enlarged mediastinal lymph nodes and underwent bronchoscopy for suspected breast cancer recurrence were included. Patients were classified into sarcoidosis/SLR or metastatic breast cancer groups, and the clinical characteristics were compared.
RESULTS: A total of 9,559 patients underwent breast cancer surgery; bronchoscopy was performed to diagnose enlarged mediastinal lymph nodes in 29 cases. Breast cancer recurrence was observed in 20 patients. Eight women with a median age of 49 years (range 38-75) and a median time from surgery to diagnosis of 4.0 years (range 0.2-10.8) were diagnosed with sarcoidosis/SLRs. Four of the eight patients underwent mammoplasty with silicone breast implants (SBIs), and two experienced postoperative recurrences of breast cancer before or after lymphadenopathy, which was considered inciting factors for SLRs. The remaining two cases could have developed sarcoidosis after breast cancer surgery with no underlying causes for SLR.
CONCLUSIONS: Postoperative sarcoidosis/SLRs rarely occur in patients with breast cancer. An adjuvant action of SBI likely contributed to the progression of SLRs; few cases exhibited a causal relationship with breast cancer recurrence.

This case represents an impressive finding of a young male who developed cutaneous sarcoid-like reactions that arose secondarily to tattoo ink. Cutaneous manifestations of sarcoidosis can present themselves in various ways, be caused by different inducing factors, and may present themselves not only cutaneously but as one of the many findings of systemic sarcoidosis. A 24-year-old black gentleman presented to the dermatology clinic with a manifestation of papules in his tattoos that covered a majority of his body. The patient tried hypoallergenic tattoo ink to see if this would prevent the formation of these bumps; however, this only further provoked the production of these papules confined to tattooed areas. Skin findings revealed linear raised papules in a continuous fashion in areas where the patient had tattoo ink on his torso, bilateral arms and legs, and face. At presentation, he denied any constitutional, pulmonary, or ophthalmologic symptoms. Pathological findings revealed sarcoidal granulomatous dermatitis showing nodular non-necrotizing granulomatous inflammatory infiltrate involving the superficial and deep dermis. The patient was then evaluated by pulmonology to rule out any systemic findings of sarcoidosis, which showed a negative chest x-ray. The patient was started on oral prednisone and topical pimecrolimus cream, and when he returned for his one-month follow-up, there were minimal to no visible cutaneous lesions. Tattoo ink has been shown to cause a variety of cutaneous reactions such as infections, neoplasms, and inflammatory dermatoses such as eczema, lichen planus, psoriasis, vitiligo, and sarcoidosis. Cutaneous sarcoid-like reactions secondary to tattoo ink are rare findings; however, they must be taken seriously due to the risk of systemic sarcoidosis involvement both at initial presentation and in the future.

Introduction Endobronchial ultrasound-guided fine-needle aspiration biopsy (EBUS-FNAB) is a minimally invasive method used to obtain cytological or histological specimens of masses and lymphadenopathies (LAP) adjacent to the trachea and bronchi. Granulomas, which represent a chronic inflammatory response and occur for a variety of reasons, like a \'sarcoid-like reaction\', cause LAPs. In this study, it was aimed to evaluate the long-term follow-up results of granulomatous lymphadenitis diagnosed with EBUS-FNAB and to investigate whether granulomatous lymphadenopathies were precursors of malignancies that occurred during the follow-up period. Material and methods The medical records of 123 patients who underwent EBUS-FNAB and were diagnosed with granulomatous lymphadenitis were retrospectively reviewed. Age, gender, acid-fast bacilli (ARB) staining, tuberculosis culture and tuberculosis polymerase chain reaction (PCR) culture results were examined by FNAB, and the procedure indications of all patients diagnosed with granulomatous lymphadenitis were recorded. The long-term health records of 52 patients could not be accessed. Data were collected from 71 patients. The progression, regression or stable conditions of LAPs in the long-term radiological follow-up of at least two years and the treatment conditions of diagnosis after biopsy were examined. Results One hundred twenty-three patients were included in the study. Rapid onset evaluation (ROSE) was performed in 93 (75.6%) patients. In 62 (66.6%) of the 93 patients, the smear results were consistent with granulomatous reaction at baseline. Malignancy was present in seven patients (5.6%) at the time of the procedure. In two patients (1.62%), tuberculous lymphadenitis was diagnosed by a positive tuberculosis culture. The long-term follow-up results were not obtained in 52 (42.7%) patients included in the study. At the long-term follow-up of six patients\' LAPs with known malignancies, three of them regressed, one of them progressed, and two of them remained stable after chemoradiotherapy. Methylprednisolone treatment was started in eight patients with the diagnosis of sarcoidosis. While LAP remained stable in five patients, regression was observed in three patients. Idiopathic LAPs remained stable in 24 of 55 patients who received no treatment and regressed spontaneously in 31 of them. One of the patients was diagnosed with lymphoma, and the other patient was diagnosed with primary lung cancer in the long-term follow-up. Conclusion In cases where tuberculosis is suspected, not only cytomorphology but also microbiological confirmation is important. Granulomatous lymphadenitis can be detected both in the disease course of patients with a history of malignancy and as a precursor to undiagnosed malignancy. So the diagnosis of granulomatous lymphadenitis is a clinicopathological diagnosis that must be followed up in patients without symptoms or other findings.

UNASSIGNED: The association between sarcoidosis and autoimmunity has been reported for years. However, the significance of autoantibodies in the pathophysiology and clinical management of sarcoidosis is not well understood. No autoantibodies that can be used as serologic biomarkers to diagnose the disease, monitor the state of the disease, and predict the prognosis of patients are established.
UNASSIGNED: We performed a comprehensive analysis of serum autoantibodies and analyzed their associations with clinical features of sarcoidosis.
UNASSIGNED: Patients with systemic autoimmune rheumatic diseases-associated autoantibodies had a higher prevalence of advanced radiographic stage and consolidations in high-resolution computed tomography than patients without autoantibodies (p < .05). Age, sex, clinical history, pulmonary function tests, serum angiotensin-converting enzyme levels, rheumatoid factor, and the number of involved organs were not significantly different between the two groups.
UNASSIGNED: There may be an association between autoantibodies and more advanced pulmonary lesions in patients with sarcoidosis. Further investigations are needed to establish the significance of autoantibodies.

BACKGROUND: Sarcoidosis is a systemic inflammatory disease that is characterized by non-caseating epithelioid-cell granulomas upon histology. However, similar histological findings may also be seen with certain infections. Thus, differentiation from infection is pivotal to ensure appropriate treatment. Here, we present a case of a disseminated infection with Mycobacterium genavense owing to an interleukin 12 receptor subunit beta 1 (IL-12Rβ1) associated immunodeficiency in a previously healthy female who was initially misdiagnosed with sarcoidosis. M. genavense is a nontuberculous mycobacterium which can cause lymphadenopathy, gastrointestinal and bone marrow infiltration in immunocompromised patients. With this case report we aim to highlight that an infection with M. genavense on the ground of a genetic defect of mycobacterial immune control may represent a rare differential diagnosis of sarcoidosis.
METHODS: A 31-year-old female was referred to our hospital with progressive lymphadenopathy, hepatosplenomegaly, pancytopenia and systemic inflammation. She had previously been evaluated for generalized lymphadenopathy in another hospital. At that time, lymph node biopsies had revealed sarcoid-like lesions and a systemic corticosteroid treatment was initiated based on a putative diagnosis of sarcoidosis. When her condition worsened, she was transferred to our university clinic, where the diagnosis of disseminated M. genavense infection owing to an inborn interferonopathy was made. Her family history revealed that her brother had also suffered from IL-12Rβ1 deficiency and had died from a systemic infection with M. genavense at the age of 21. The patient received antimycobacterial treatment combined with subcutaneous type I interferon, which eventually led to a gradual improvement over the next months.
CONCLUSIONS: Differentiating between sarcoidosis and sarcoid-like lesions secondary to infections may be challenging, especially when pathogens are difficult to detect or not expected in an apparently immunocompetent patient. Patients with IL-12Rβ1-associated immunodeficiency may be asymptomatic until adulthood, and disseminated M. genavense infection on the grounds of an IL-12Rβ1-associated immunodeficiency may represent a rare differential diagnosis of sarcoidosis.