title: Characteristics of Sarcoidosis in Patients with Previous Malignancy: Causality or Coincidence?
abstract: BACKGROUND
  The association between sarcoidosis and malignancy is poorly defined. Sarcoidosis can precede, be diagnosed concurrently with, or follow malignancy.
  
  
  OBJECTIVE
  We describe the clinical and radiological features of patients with sarcoidosis following malignancy to determine whether this association is causal or coincidental.
  
  
  METHODS
  We performed a search for all patients with confirmed sarcoidosis following malignancy in our institution during 2001-2015. Clinical and radiological features, bronchoscopic findings, bronchoalveolar lavage cell counts, and pulmonary function tests (PFTs) were reviewed to evaluate patterns of disease involvement. Details of the histological type of cancer, staging, treatment, and follow-up were reviewed.
  
  
  RESULTS
  Twenty-nine patients were identified. The most prevalent malignancies were breast cancer and lymphoma (24% each). Based on the incidence of these malignancies, we estimated the incidence of sarcoidosis was 175 times higher after lymphoma and 38 times higher after breast cancer as compared to the general population. Most patients had early stage cancer (stage I, II) (75%), and only 2 patients (7%) had recurrence of their malignancy after diagnosis of sarcoidosis. Sarcoidosis was diagnosed within 5 years of malignancy in over half the patients, 76% were asymptomatic and 69% had normal PFTs. Mediastinal lymphadenopathy was present in 81% of cases, hilar lymphadenopathy in 67%, and pulmonary parenchymal involvement in 41%. Fifty percent of patients had received Adriamycin, 38% cyclophosphamide, and 33% vincristine.
  
  
  CONCLUSIONS
  Sarcoidosis following malignancy is indistinguishable from "idiopathic" sarcoidosis, although it is frequently asymptomatic. The high frequency of sarcoidosis after specific cancers but not others, suggests a causative association between malignancy and development of sarcoidosis.
authors.affiliation: Institute of Pulmonary Medicine, Hadassah - Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Nissim
authors.initials: N
authors.lastname: Arish
authors.forename: Rottem
authors.initials: R
authors.lastname: Kuint
authors.forename: Eli
authors.initials: E
authors.lastname: Sapir
authors.forename: Liran
authors.initials: L
authors.lastname: Levy
authors.forename: Avraham
authors.initials: A
authors.lastname: Abutbul
authors.forename: Zvi
authors.initials: Z
authors.lastname: Fridlender
authors.forename: Uri
authors.initials: U
authors.lastname: Laxer
authors.forename: Neville
authors.initials: N
authors.lastname: Berkman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000150:complications; D005260:Female; D006801:Humans; D000072281:Lymphadenopathy / Q000209:etiology; D008223:Lymphoma / Q000150:complications; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications*; D012507:Sarcoidosis / Q000209:etiology*