Coal worker’s pneumoconiosis and sarcoid-like reaction mimicking lymph node metastases in a patient with lung cancer: A case report
Sarcoid-like reactions occur in a small percentage of cancer patients. This reaction causes lymph nodes to appear hypermetabolic when viewed with Fludeoxyglucose-Positron Emission Tomography (FDG-PET). This is clinically important, because it could be confused with tumor metastasis and could affect the staging and treatment of the cancer. In addition to sarcoid-like reactions and metastasis, several other disease processes can cause lymph nodes to appear hypermetabolic with FDG-PET, including coal worker’s pneumoconiosis. We present the case of a 61-year-old coal miner who was diagnosed with lung cancer. FDG-PET showed increased uptake in ipsilateral and contralateral mediastinal lymph. The patient had bronchoscopy with endobronchial ultrasound (EBUS) guided biopsy of the mass and needle aspiration of bilateral lymph nodes of the mediastinum. All the biopsies were negative. The patient then had a left upper lobectomy and left mediastinal lymph node dissection. The PET findings were originally attributed to metastasis of the tumor, but pathology of the ipsilateral nodes showed silicotic changes due to pneumoconiosis and non-caseating granulomas from a sarcoid-like reaction. Because the ipsilateral lymph nodes had no evidence of metastasis and EBUS biopsy of the contralateral nodes was negative, it was unlikely that the changes in the contralateral nodes were due to metastasis, and no adjuvant treatment was offered. At more than one year after surgery, the patient remains stable with no evidence of recurrence, and we have clinical assurance that the changes in the lymph nodes were due to the sarcoid-like reaction and pneumoconiosis and not metastasis. FDG-PET is useful for detection of lung cancer, but pathology is necessary for staging and determining treatment for the patient.
Keywords: lung neoplasms, anthracosis, sarcoid-like reaction, fludeoxyglucose-positron emission tomography
Jett JR, Schild SE, Keith RL, Kesler KA. Treatment of nonsmall
cell lung cancer, stage IIIB: ACCP evidence-based
clinical practice guidelines (2nd edition). Chest. 2007;132
Craun JB, Banks KP, Clemenshaw MN, Moren RW. Sarcoidlike
reaction of neoplasia causing hypermetabolic thoracic
adenopathy in setting of extrathoracic malignancy:
report of two cases and a review of the differential diagnostic
considerations. J Nucl Med Technol. 2012;40(4):
Chowdhury FU, Sheerin F, Bradley KM, Gleeson FV. Sarcoid-
like reaction to malignancy on whole-body integrated
(18)F-FDG PET/CT: prevalence and disease pattern. Clin
Aoki K, Yoshimura K, Hoashi S, Ushio T, Tai H, Itsubo K,
et al. Lung cancer with a sarcoid-like reaction in the primary
tumor. Japanese Journal of Thoracic Diseases. 1997;35(4):
Kudo K, Sakamoto S, Miyamoto A, Kono T, Motoi N,
K. A case of large cell carcinoma of the lung associated
with a sarcoid-like reaction inside the tumor. The Journal
of the Japanese Respiratory Society. 2008;46(11):889–893.
Mirsadraee M. Anthracosis of the lungs: etiology, clinical
manifestations and diagnosis: a review. Tanaffos. 2014;13(4):
Pinaquy JB, Fernandez P, Pasticier G, Parrens M, De
H. Anthracosis mimicking mediastinal lymph
node metastases with 18F-FCholine in high-risk prostate
cancer. Clin Nucl Med. 2015;40(4):e253–254.
Hewitt RJ, Wright C, Adeboyeku D, Ornadel D, Berry M,
Wickremasinghe M, et al. Primary nodal anthracosis identified
by EBUS-TBNA as a cause of FDG PET/CT positive
mediastinal lymphadenopathy. Respiratory Medicine Case
Saydam O, Gokce M, Kilicgun A, Tanriverdi O. Accuracy
of positron emission tomography in mediastinal node
assessment in coal workers with lung cancer. Med Oncol.
Reichert M, Bensadoun ES. PET imaging in patients with
coal workers pneumoconiosis and suspected malignancy.
J Thorac Oncol. 2009;4(5):649–651.
Cheng NM, Yeh TW, Ho KC, Ng SH, Hsueh C, Yen TC, Liao
CT. False positive F-18 FDG PET/CT in neck and mediastinum
lymph nodes due to anthracosis in a buccal cancer
patient. Clin Nucl Med. 2011;36(10):963–964.
Bilici A, Erdem T, Boysan SN, Acbay O, Oz B, Besirli K,
Gungdogdu S. A case of anthracosis presenting with mediastinal
lymph nodes mimicking tuberculous lymphadenitis or
malignancy. Eur J Intern Med. Vol 142003:444–446.