Yi, Eunhee S.

ObjectiveTo investigate clinical and pathologic aspects of IgG4‐related disease (IgG4‐RD) in non‐Asian populations.MethodsWe conducted a retrospective review of the medical records of patients with IgG4‐RD who presented to an academic medical center from January 1994 to September 2012.ResultsAmong 166 patients identified, the median age at diagnosis was 61 years (interquartile range [IQR] 49–70 years), 75% were male, and 80% were white. The median number of organs involved was 2 (IQR 2–3). When organs were grouped according to anatomic system, the hepatopancreaticobiliary system was most commonly involved (77%). The median highest serum IgG4 level during the clinical course was 215 mg/dl (IQR 122–466). Forty‐three patients (26%) had a normal serum IgG4 level. Seventy‐nine pathology specimens were available for immunostaining. The median number of IgG4+ cells was 37 (IQR 25–82) per high‐power field, with an IgG4+:IgG+ ratio of 0.50 (IQR 0.32–0.68). Among 151 patients who received medical therapy, 72 (48%) received steroid‐sparing agents because of relapse, recurrence, or corticosteroid intolerance. Of the 66 patients who were newly diagnosed, started on corticosteroid monotherapy as the initial treatment, and followed up at our institution, 30 (45%) experienced relapse or recurrence despite an initial favorable response. The number of organs involved had a significant impact on time to relapse or recurrence, with a hazard ratio of 1.48 (95% confidence interval [95% CI] 1.12–1.93) (P < 0.01) in multivariate analysis. The standardized incidence ratio of malignancy was 4.5 (95% CI 1.5–7.5).Conclusion. IgG4‐RD is a multisystem disorder that commonly affects older men and has a propensity for relapse, recurrence, and malignancy.

Diffuse pulmonary lymphangiomatosis (DPL) is a rare disease characterized by infiltration of the lung, pleura and mediastinum with thin-walled lymphangiomas. DPL can result in mass effect from infiltrative disease, restrictive and obstructive pulmonary physiology, chylous effusions and respiratory failure. The present article discusses clinical, radiographic and pathological features, and treatment options for DPL.

Context Pulmonary Langerhans cell histiocytosis (PLCH) is a rare histiocytic disorder that almost exclusively affects the lungs of smokers. PLCH is characterized by bronchiolocentric nodules and/or cysts in an upper and mid lung distribution with sparing of the costophrenic angles. The diagnosis can be challenging and often requires transbronchial biopsy or surgical lung biopsy. Pulmonary hypertension is a relatively common and sometimes severe complication of PLCH. The pathogenesis of PLCH is still debated. Recently, BRAF V600E mutation and BRAF expression have been identified in some patients with PLCH, suggesting that at least a subset of PLCH has a clonal proliferation. While smoking cessation is the first-line treatment of PLCH, some patients might require additional treatment and eventually transplant. Given that the lesional cells of PLCH express BRAF in some patients, MAPKinase pathway–targeted treatment might be useful for therapy-resistant patients. Objective —To present the more recently recognized clinical and pathologic aspects of PLCH, including pulmonary hypertension in PLCH, pathogenesis, and treatment, as well as the basic diagnostic approach to PLCH. Data Sources Authors' own research, and search of literature database (PubMed) and UpToDate. Conclusions —Despite the recent progress, more studies are needed to elucidate the biology of PLCH for identification of prognostic factors and appropriate treatment options, especially for therapy-refractory PLCH cases.

Abstract Purpose: The expression of programmed cell death ligand 1 (PD-L1) provides limited predictive value in identifying patients most likely to respond to immunotherapy. As the heterogeneity of PD-L1 expression may lead to sampling error and the misclassification of PD-L1 status, we assessed the distribution of PD-L1 expression in paired, resected multifocal lung cancers. Experimental Design: PD-L1 was assessed by IHC. Paired lesions were defined as independent primaries or related lesions using mate pair next-generation sequencing. Agreement statistics were used for analysis. Results: Sixty-seven multifocal lung cancers from 32 patients were sequenced and stained for PD-L1. There was agreement of PD-L1 expression by the tumor cells in paired lesions of 20 patients and disagreement of PD-L1 expression by the tumor cells in paired lesions of 12 patients (κ = 0.01). Sequencing identified that 23 patients had independent primary lung cancers and that 9 patients had related cancers. In paired lesions of patients with independent cancers, there was agreement of PD-L1 expression by the tumor cells in 12 patients and disagreement in 11 patients (κ = 0.31). In paired lesions of patients with related lung cancers, there was agreement of PD-L1 expression by the tumor cells in 8 patients and disagreement in 1 patient (κ = 0.73). Conclusions: The expression of PD-L1 is heterogeneous among paired independent lung cancers, but there are high levels of agreement in intrapulmonary metastasis. Clin Cancer Res; 22(9); 2177–82. ©2015 AACR.

AbstractMalignancy has a complicated association with immunoglobulin G4‐related disease (IgG4‐RD) both being an item in the differential diagnosis as well as malignancy occurring in the background of IgG4‐RD in the same organ. However, recently there is evidence of higher rates of distant malignancy in patients with IgG4‐RD. Here we report a case of pulmonary IgG4‐RD potentially consistent with a paraneoplastic phenomenon which improved with treatment of the underlying colon adenocarcinoma.

Transbronchial cryobiopsy technique yields larger biopsies with enhanced quality. The benefits and safety of cryobiopsies have not been thoroughly studied in lung allografts.Context.— To compare size, quality, reproducibility of interpretation of rejection and complications of cryobiopsies with those of conventional biopsies from lung allografts.Objective.— All cryobiopsies (March 2014–January 2015) of lung allografts performed at Mayo Clinic, Rochester, and medical records were reviewed. For comparison, conventional biopsies from the same patient or, if unavailable, from a random patient, were selected. Two pathologists blinded to outcome reviewed all biopsies. Specimen volume, number of alveoli, small airways, and pulmonary vessels were counted and statistically compared.Design.— Fifty-four biopsies (27 cryobiopsies) from 18 patients (11 men) were reviewed. A median of 3 (range, 2–5) and 10 (range, 6–12) specimens were obtained with cryobiopsies and conventional biopsies, respectively. Cryobiopsies were larger and contained more alveoli (P &lt; .001, both) and small airways (P = .04). Conventional biopsies showed more fresh alveolar hemorrhage (procedural) and crush artifact/atelectasis (P &lt; .001, both). Cryobiopsies contained more pulmonary veins and venules (P &lt; .001). There was no significant difference between the types of biopsies with respect to the reviewers' agreement on grades of rejection. Complications were more frequent in the cryobiopsy group, though the difference was not statistically significant.Results.— Cryobiopsies of lung allografts are larger and have less artifact. However, complications occur and should be considered. Three cryobiopsy specimens appear sufficient for histopathologic evaluation of lung allografts.Conclusions.—

OBJECTIVE: Aspiration can cause a variety of pulmonary syndromes, some of which are not well recognized. The objective of this study was to assess the demographic, clinical, radiological, and histopathological correlates of diffuse aspiration bronchiolitis (DAB), a bronchiolocentric disorder caused by recurrent aspiration. METHODS: This was a retrospective study of 20 consecutive patients with DAB seen at the Mayo Clinic in Rochester, Minnesota, between January 1, 1998 and June 30, 2014. RESULTS: The median age of the patients was 56.5 years (range, 22-76 years), and the male/female ratio was 2.3:1.0. In 18 patients, the diagnosis of DAB was based on the results of a lung biopsy; in the 2 remaining patients, it was based on clinical and radiological features, together with documented aspiration observed in a videofluoroscopic swallow study. In 19 patients (95%), we identified predisposing factors for aspiration, including gastroesophageal reflux disease (GERD), drug abuse, and dysphagia. Common presenting features included cough, sputum production, dyspnea, and fever. Twelve patients (60%) had a history of recurrent pneumonia. In all of the patients, chest CT revealed bilateral pulmonary infiltrates consisting of micronodules and tree-in-bud opacities. In the majority of patients, interventions aimed at preventing recurrent aspiration (e.g., anti-GERD therapies) led to improvement in the symptoms of DAB. CONCLUSIONS: Young to middle-aged subjects with recognizable predisposing factors for aspiration and who report a history of recurrent pneumonia are at increased risk for DAB. Although DAB is not well recognized, certain chest CT features are characteristic of the disorder.

Purpose Distinguishing independent primary tumors from intrapulmonary metastases in non–small-cell carcinoma remains a clinical dilemma with significant clinical implications. Using next-generation DNA sequencing, we developed a chromosomal rearrangement–based approach to differentiate multiple primary tumors from metastasis. Methods Tumor specimens from patients with known independent primary tumors and metastatic lesions were used for lineage test development, which was then applied to multifocal tumors. Laser capture microdissection was performed separately for each tumor. Genomic DNA was isolated using direct in situ whole-genome amplification methodology, and next-generation sequencing was performed using an Illumina mate-pair library protocol. Sequence reads were mapped to the human genome, and primers spanning the fusion junctions were used for validation polymerase chain reaction. Results A total of 41 tumor samples were sequenced (33 adenocarcinomas [ADs] and eight squamous cell carcinomas [SQCCs]), with a range of three to 276 breakpoints per tumor identified. Lung tumors predicted to be independent primary tumors based on different histologic subtype did not share any genomic rearrangements. In patients with lung primary tumors and paired distant metastases, shared rearrangements were identified in all tumor pairs, emphasizing the patient specificity of identified breakpoints. Multifocal AD and SQCC samples were reviewed independently by two pulmonary pathologists. Concordance between histology and genomic data occurred in the majority of samples. Discrepant tumor samples were resolved by genome sequencing. Conclusion A diagnostic lineage test based on genomic rearrangements from mate-pair sequencing demonstrates promise for distinguishing independent primary from metastatic disease in lung cancer.