Sarcoidosis-Like Cancer-Associated Granulomatosis: Characteristics and a Case-Control Comparison with Sarcoidosis

Ultrathin bronchoscopy-guided small airway biopsy for diagnosing sarcoidosis: A prospective study

New ultrathin bronchoscopes (UTBs) enable the inspection and biopsy of small airways, potentially offering diagnostic advantages in sarcoidosis. In this prospective study, patients with suspected sarcoidosis underwent airway inspection with a UTB. Observed airway abnormalities were categorised into six predefined patterns. UTB-directed small airway biopsies (SABs) were collected from the upper lobes following a standardised procedure. We evaluated the prevalence and patterns of SAAs, as well as the diagnostic yield of UTB-directed SAB. Among 79 participants, 65 (82.3%) were diagnosed with sarcoidosis. Small airway abnormalities were identified in 26/65 (40%) patients, predominantly in those with parenchymal involvement on CT compared to those with lymphadenopathy only (58.1% VS. 23.5%, P = 0.005). The diagnostic yield of SABs for detecting granulomas was significantly higher in patients with SAAs than in those without (65.4% VS. 23.1%, P = 0.001) and in patients with parenchymal disease on CT compared to those without (54.8% VS. 26.5%, P = 0.02). Notably, random biopsies taken under direct visualisation from small airway carinas revealed peribronchiolar parenchyma in 23% of the patients. Small airway abnormalities are prevalent in sarcoidosis patients with parenchymal involvement, and biopsying these abnormalities yields a high rate of granuloma detection.

Sarcoid-like reaction in patients with malignant tumors: Long-term clinical course and outcomes

Background

The development of non-caseating epithelioid cell granulomas in cancer patients who do not fulfill the systemic sarcoidosis criteria is termed sarcoid-like reaction (SLR). Little is known about this condition's natural course and impact on the prognosis of malignancy. We aimed to investigate the natural course and prognostic value of cancer-associated SLR.

Methods

Clinical data were retrospectively analyzed in 32 patients with biopsy-proven cancer-associated SLR. Among patients with non-small cell lung cancer (NSCLC), SLR cases (n = 8) were matched with non-SLR cases (n = 78) for survival analysis.

Results

Among the included patients, the mean age was 59.7 years, and 68.8% were female. The median follow-up period was 35.6 months [interquartile range (IQR): 14.0–61.4 months]. Of all the included malignancies (n = 32), breast cancer (25.0%) and NSCLC (25.0%) were the most common, with stage I being the most frequent tumor stage (59.4%). During follow-up, SLR progression to overt sarcoidosis was not observed. In the 28 patients with available follow-up computed tomography images (median interval: 24.9 months; IQR: 14.4–41.7), 4 patients received corticosteroids (n = 4), resulting to a decrease of SLR lesions. Meanwhile, among those who did not receive treatment (n = 24), the extent of SLR decreased or did not change in 85.7% of them, whereas 3.6% had increased SLR extent. Furthermore, among patients with NSCLC, SLR was not associated with overall survival [hazard ratio (HR) = 1.28, 95% confidence interval (CI): 0.02–67.71, P = 0.882] and recurrence of malignancy (HR = 1.27, 95% CI 0.21–7.51, P = 0.793) in the Cox proportional hazard regression model.

Conclusions

During the follow-up of cancer-related SLR, we found no further evidence for systemic sarcoidosis, and most of the lesions decreased or did not change. Development of SLR was also not associated with overall survival or disease-free survival in patients with NSCLC.

Pulmonary Sarcoidosis: Diagnosis and Differential Diagnosis

Sarcoidosis is a multisystem disorder of unknown origin and poorly understood pathogenesis that predominantly affects lungs and intrathoracic lymph nodes and is characterized by the presence of noncaseating granulomatous inflammation in involved organs. The disease is highly heterogeneous and can mimic a plethora of other disorders, making diagnosis a challenge even for experienced physicians. The evolution and severity of sarcoidosis are highly variable: many patients are asymptomatic and their disease course is generally benign with spontaneous resolution. However, up to one-third of patients develop chronic or progressive disease mainly due to pulmonary or cardiovascular complications that require long-term therapy. The diagnosis of sarcoidosis requires histopathological evidence of noncaseating granulomatous inflammation in one or more organs coupled with compatible clinical and radiological features and the exclusion of other causes of granulomatous inflammation; however, in the presence of typical disease manifestations such as Löfgren’s syndrome, Heerfordt’s syndrome, lupus pernio and asymptomatic bilateral and symmetrical hilar lymphadenopathy, the diagnosis can be established with high level of certainty on clinical grounds alone. This review critically examines the diagnostic approach to sarcoidosis and emphasizes the importance of a careful exclusion of alternative diagnoses.