Pneumonitis After Concurrent Chemoradiation and Immune Checkpoint Inhibition in Patients with Locally Advanced Non-small Cell Lung Cancer.

AIMS: Pneumonitis is a common and potentially deadly complication of combined chemoradiation and immune checkpoint inhibition (CRT-ICI) in patients with locally advanced non-small cell lung cancer (LA-NSCLC). In this study we sought to identify the risk factors for pneumonitis with CRT-ICI therapy in LA-NSCLC cases and determine its impact on survival. MATERIALS AND METHODS: We conducted a retrospective chart review of 140 patients with LA-NSCLC who underwent curative-intent CRT-ICI with durvalumab between 2018 and 2021. Pneumonitis was diagnosed by a multidisciplinary team of clinical experts. We used multivariable cause-specific hazard models to identify risk factors associated with grade ≥2 pneumonitis. We constructed multivariable Cox proportional hazard models to investigate the impact of pneumonitis on all-cause mortality. RESULTS: The median age of the cohort was 67 years; most patients were current or former smokers (86%). The cumulative incidence of grade ≥2 pneumonitis was 23%. Among survivors, 25/28 patients had persistent parenchymal scarring. In multivariable analyses, the mean lung dose (hazard ratio 1.14 per Gy, 95% confidence interval 1.03-1.25) and interstitial lung disease (hazard ratio 3.8, 95% confidence interval 1.3-11.0) increased the risk for pneumonitis. In adjusted models, grade ≥2 pneumonitis (hazard ratio 2.5, 95% confidence interval 1.0-6.2, P = 0.049) and high-grade (≥3) pneumonitis (hazard ratio 8.3, 95% confidence interval 3.0-23.0, P < 0.001) were associated with higher all-cause mortality. CONCLUSIONS: Risk factors for pneumonitis in LA-NSCLC patients undergoing CRT-ICI include the mean radiation dose to the lung and pre-treatment interstitial lung disease. Although most cases are not fatal, pneumonitis in this setting is associated with markedly increased mortality.

Utility of early versus late fiberoptic bronchoscopy in the evaluation of new pulmonary infiltrates following hematopoietic stem cell transplantation.

Pulmonary infiltrates frequently complicate hematopoietic SCT (HSCT). The utility of fiberoptic bronchoscopy (FOB) with bronchoalveolar lavage (BAL) in the evaluation of new pulmonary infiltrates, particularly as it relates to optimal timing of the procedure, is unclear. Based on this, we retrospectively reviewed 501 consecutive, adult, nonintubated patients who underwent 598 BALs for evaluation of new pulmonary infiltrates during the first 100 days following HSCT to determine whether diagnostic yields for infection, subsequent antimicrobial treatment modifications and patient outcomes differed following early vs late referrals for the procedure. The overall yield of BAL for clinically significant pathogens was 55%. Notably, the yield was 2.5-fold higher among FOBs performed within the first 4 days of presentation (early FOB) compared to those performed late, and highest (75%) when performed within 24 h of clinical presentation. Rates of FOB-guided adjustments in antimicrobial therapy (51%) did not differ significantly between early and late examinations. However, late FOB-related antibiotic adjustments were associated with 30-day pulmonary-associated deaths that were threefold higher (6 vs 18%, P=0.0351). Major FOB-related complications occurred in only three (0.6%) patients. We conclude that early referral for FOB in this patient setting is associated with higher diagnostic yields and may favorably impact survival.

Outcome of alveolar hemorrhage in hematopoietic stem cell transplant recipients.

Alveolar hemorrhage (AH) is a frequent, serious complication of hematopoietic stem cell transplantation (HSCT). To study the incidence of AH, its clinical course and outcomes in HSCT patients, a retrospective review of the records of all adult patients who underwent bronchoscopy between January 1, 2002 and December 31, 2004 was carried out and those who underwent bronchoscopy after HSCT identified. A total of 223 patients underwent bronchoscopy after HSCT for diffuse pulmonary infiltrates with respiratory compromise. Eighty-seven (39%) patients had AH. Of these, 53 had AH without any identified organism while 34 had an organism along with hemorrhage on bronchoalveolar lavage (BAL). Six-month survival rate of patients with AH was 38% (95% confidence interval: 27-48%). In 95 of the 223 patients, an organism was isolated from BAL. These patients had poor outcomes compared to patients in whom no organism was identified. Patients with both AH and an organism had the worst prognosis. Mortality of patients with AH is improving and long-term survival of patients with AH is feasible. Isolation of a microbial organism in BAL is a strong predictor of poor outcome.

Idiopathic pneumonia syndrome after high-dose chemotherapy and autologous hematopoietic stem cell transplantation for high-risk breast cancer.

Our aim was to describe the incidence, clinical course, and risk factors for idiopathic pneumonia syndrome (IPS) after high-dose chemotherapy with cyclophosphamide, carmustine, and thiotepa followed by autologous stem cell transplantation for high-risk breast cancer. Charts for patients who underwent high-dose chemotherapy for high-risk breast cancer at a single center from 1992 to 2000 were retrospectively reviewed, and potential risk factors for development of IPS were sought with the log-rank test. Of 164 patients reviewed, 20 developed IPS at a median onset of 87 days after the transplant (range, 2-257 days). The actuarial incidence of IPS in the first 100 days after the transplant was 8%, and 95% of patients developed symptoms within the first 6 months after transplant. Patient age, smoking status, breast cancer stage at diagnosis, and pretransplant lung function did not predict development of IPS. Three patients died of progressive pulmonary failure and the IPS resolved in the other 17. We concluded that IPS is an important cause of morbidity and mortality in patients with high-risk breast cancer undergoing high-dose chemotherapy. Given the absence of predictive factors, any pulmonary symptoms appearing in the first year after the transplant should be evaluated carefully.

Prognostic indicators for blood and marrow transplant patients admitted to an intensive care unit.

Although hematopoietic stem cell transplantation (HSCT) can be curative in patients with certain malignancies, survival is poor if the recipient becomes critically ill. This prospective study examined the outcomes of 115 consecutive HSCT patients admitted to the medical intensive care unit (MICU) of a tertiary cancer center and identified variables associated with survival. The need for endotracheal intubation and mechanical ventilation ("intubation") had a profound adverse effect on survival. Overall, 9 of 48 (18.8%) intubated patients survived compared with a survival rate of 44 of 67 (65.7%) among patients not intubated (p < 0.001). This pattern persisted for nearly all patient subgroups. Among intubated patients, those receiving peripheral blood stem cell transplant (PBSCT) had significantly better survival than bone marrow transplant (BMT) patients (8 of 26, 31% versus 1 of 22, 4%; p = 0.028). Multiple logistic regression analyses indicated that the probability a patient admitted to the MICU survived decreased significantly if the patient was intubated, had an allogeneic rather than autologous transplant, had an infection or gastrointestinal bleeding, and also decreased with higher respiratory rate, higher heart rate, longer time from transplant to MICU admission or higher bilirubin. These results may be of value in deciding which critically ill patients will benefit from intubation following major complications after HSCT transplantation.

Malignant pleural mesothelioma after radiation therapy for breast cancer. A report of two additional patients.

BACKGROUND: Malignant pleural mesotheliomas (MPMs) are rare tumors that usually have a fatal outcome. The association of these tumors with asbestos exposure is well established. Induction of malignant mesothelioma by nonasbestos-related causes also has been reported in the literature, although the number of documented cases is extremely small. Two additional patients with malignant pleural mesothelioma many years after radiotherapy for breast cancer are reported. METHODS: The observations as reported in the literature on the involvement of radiation in the development of MPMs are reviewed and compared with the authors' clinical experience. In a retrospective random review, 1000 patients who received thoracic irradiation at M. D. Anderson Cancer Center were studied for histologic and radiographic evidence of MPM. The selection criteria included the development of a unilateral pleural effusion years after successful treatment with thoracic irradiation for a proven malignancy. Patients with a history compatible with asbestos exposure were excluded from the review. RESULTS: There have been only three previous cases of documented MPM associated with thoracic irradiation reported in the English literature. A review of the experience at our institution has demonstrated three patients with radiation-induced MPM. One patient has been reported elsewhere. Details of the other two patients are discussed in this paper. CONCLUSIONS: Nonasbestos-related causes of MPMs are rare. The additional two patients lend added support to the association between thoracic irradiation and the development of MPM. The development of a unilateral pleural effusion occurring years after successful treatment of a proven malignancy with thoracic irradiation should alert the clinician to the possibility of MPM.

Epidermis contains platelet-type 12-lipoxygenase that is overexpressed in germinal layer keratinocytes in psoriasis.

Human epidermal cells exhibited none of the cytosolic lipoxygenase activity that is prominent in mucosal epithelial cells, but instead contained a microsomal activity that converted arachidonic acid to 12-hydroxyeicosatetraenoic acid (12-HETE). Identification of the extractable 12-HETE-forming activity as a 12-lipoxygenase (distinct from cytochrome P-450) included (S)-12-stereospecificity of product formation, trapping of 12-hydroperoxyeicosatetraenoic acid as an intermediate reaction product, and lack of NADPH dependence for activity. Epidermal cell poly(A)+ RNA contained high levels of a 2.3-kb mRNA that selectively hybridized with human platelet 12-lipoxygenase cDNA, and partial cDNA sequence of this mRNA indicated identity to platelet 12-lipoxygenase. The epidermal 12-lipoxygenase was not recognized by antibodies against the leukocyte-type 12- and 15-lipoxygenases (found in leukocytes, reticulocytes, and mucosal epithelial cells) but was detected by an antiplatelet 12-lipoxygenase antibody. The epidermal 12-lipoxygenase antigen was selectively expressed in germinal layer keratinocytes in healthy and psoriatic skin, and these layers exhibited hyperplasia and increased immunostaining in inflamed psoriatic skin. Together with previous results, these observations indicate that 1) epidermis generates 12-HETE by either cytochrome P-450 or lipoxygenase-based mechanisms depending on reaction conditions, and 2) 12-lipoxygenases (originally described in hematopoietic cell types) may be expressed in at least two distinct isoforms in epithelial barriers in humans, and in the case of the skin, a microsomal (platelet-type) 12-lipoxygenase is selectively overexpressed in germinal layer keratinocytes during psoriatic inflammation.

Histochemical evidence for induction of arachidonate 15-lipoxygenase in airway disease.

We have previously described the distribution of the arachidonate 15-lipoxygenase in lung tissue obtained from healthy human subjects. In the present study, we have utilized the same immunohistochemical methodology to examine the expression of 15-lipoxygenase in bronchial biopsy tissue from subjects with airway disease. Immunohistochemistry of bronchial tissue using two antibodies against distinct epitopes of the 15-lipoxygenase and indirect biotin-avidin-peroxidase detection demonstrated that, in contrast to airway tissue from normal subjects (n = 10) in which 15-lipoxygenase antigen was confined to the uppermost airways (nose and trachea) and was almost undetectable in bronchi, the bronchial tissue obtained from subjects with asthma (n = 7) or chronic bronchitis (n = 7) exhibited markedly positive immunostaining of mucosal epithelial cells with both anti-15-lipoxygenase antibodies. Specificity of 15-lipoxygenase immunostaining was verified by antigen competition experiments and by the lack of immunostaining with preimmune serum or control anti-5-lipoxygenase antibodies. The increased levels of 15-lipoxygenase antigen in the bronchial epithelial cells of asthmatic and bronchitic subjects compared with the same cell population in normal subjects coupled with the previous findings of increased 15-lipoxygenase activity in asthmatic airways suggest that epithelial 15-lipoxygenase is induced by airway inflammatory disease.

Induction of epithelial arachidonate 12-lipoxygenase at active sites of inflammatory bowel disease.

To determine if epithelial lipoxygenases are regulated by mucosal inflammation, we examined the distribution of arachidonate 12-lipoxygenase in healthy colonic tissue and in involved and uninvolved sections of colon with inflammatory bowel disease. Immunohistochemistry of formaldehyde-fixed, paraffin-embedded intestinal tissue using two anti-12-lipoxygenase antibodies and indirect biotin-avidin-peroxidase detection demonstrated that, in contrast to tissue from normal colon (n = 8), in which 12-lipoxygenase antigen was undetectable in mucosal epithelial cells, the mucosal and glandular epithelium of inflamed colon in ulcerative colitis (n = 4) or Crohn's disease (n = 4) exhibited markedly positive immunostaining with anti-12-lipoxygenase antibodies. Immunoblotting of whole cell extracts with anti-12-lipoxygenase antibodies showed immunoperoxidase staining of a single protein band that comigrated with purified 12-lipoxygenase (in relative molecular weight: M(r) = 72,000) in mucosal samples from inflamed colon from subjects with ulcerative colitis or Crohn's disease but no comparable band in samples from uninvolved sections of the same colons or from colons of subjects without inflammatory bowel disease. Assays of 12-lipoxygenase activity indicated a corresponding increase in enzymatic activity in the same mucosal samples. The increased levels of 12-lipoxygenase antigen in the mucosal and glandular epithelial cells in regions of colon affected by inflammatory bowel disease, the corresponding increases in 12-lipoxygenase activity, and the absence of detectable 12-lipoxygenase antigen or enzymatic activity in the same cell types in noninflamed colonic tissue all suggest that epithelial cell 12-lipoxygenase is induced by local mediators of colonic inflammation.

Selective expression of an arachidonate 12-lipoxygenase by pancreatic islet beta-cells.

The immunohistochemical distribution of arachidonate lipoxygenases in rat pancreas was characterized with specific polyclonal anti-5-lipoxygenase and anti-12-lipoxygenase antibodies. Immunohistochemical analysis of formaldehyde-fixed paraffin-embedded rat pancreas using anti-12-lipoxygenase antibody and biotin-avidin-peroxidase detection demonstrated specific staining of islets and no staining of pancreatic exocrine tissue. Less intense staining of pancreatic vascular myocytes and endothelial cells was also observed. Immunoblotting of isolated pancreatic islet extracts with the anti-12-lipoxygenase antibody demonstrated immunoperoxidase staining of a single protein band which comigrated with purified 12-lipoxygenase (relative molecular weight = 72,000) on sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. Dispersed cells prepared from isolated islets and then subjected to fluorescence-activated cell sorting and immunostaining exhibited 12-lipoxygenase antigen in beta-cell populations but not in non-beta-cell (predominantly alpha-cell) populations. Assays of enzymatic activity confirmed that the 12-lipoxygenase-catalyzed conversion of arachidonic acid to 12-hydroxyeicosatetraenoic acid methyl ester occurred only with purified beta-cells and not with islet non-beta-cells. No evidence of 5-lipoxygenase antigen or enzymatic activity was found in purified beta-cells or in islet non-beta-cells. We conclude that rat pancreatic islet beta-cells contain an arachidonate 12-lipoxygenase which shares antigenic epitopes with the homologous enzyme contained in tissues from other species. In addition, the selective localization of the 12-lipoxygenase to pancreatic beta-cells and its absence in pancreatic acinar cells and in islet non-beta-cells support observations suggesting that 12-lipoxygenase products may participate in glucose-induced insulin secretion from beta-cells.

Related expression of arachidonate 12- and 15-lipoxygenases in animal and human lung tissue.

We examined the immunohistochemical distribution of the arachidonate 12- and 15-lipoxygenases in animal and human lung tissue using a polyclonal anti-12/15-lipoxygenase antibody. Immunoblotting of whole cell extracts from bovine and human tracheal epithelial cells or from bovine leukocytes with the antibody (raised originally against purified porcine leukocyte 12-lipoxygenase) showed immunoperoxidase staining of a single protein band (Mr = 72,000), which comigrated with purified bovine 12-lipoxygenase. The antibody also immunoprecipitated both 12- and 15-lipoxygenase activities from cytosolic fractions of bovine and human tracheal epithelial cells. Immunohistochemistry of formaldehyde-fixed and paraffin-embedded bovine (and ovine and canine) trachea using the same polyclonal antibody and an indirect biotin-avidin-peroxidase detection system demonstrated specific staining of tracheal epithelium, polymorphonuclear and mononuclear leukocytes, and perineural cells. Less intense staining of submucosal glands and blood vessels was also observed. Lung sections demonstrated that the level of lipoxygenase antigen decreased markedly by the level of the bronchi and was absent in more distal airways. A similar pattern of immunostaining was found in human lung, except that airway smooth muscle was also weakly reactive, and polymorphonuclear (neutrophilic) leukocytes were unstained (in accordance with the low 12/15-lipoxygenase activity in this cell type). We conclude that animal and human epithelial 12/15-lipoxygenases share enzymatic, antigenic, and regional distribution characteristics and may therefore possess a common function in the pulmonary airway.

Biochemical and immunohistochemical evidence for selective expression of novel epithelial lipoxygenases.

Human tracheal epithelial cells contain an arachidonate 15-lipoxygenase, while the same cells from animals (including bovine, ovine, canine, porcine) cells express a 12-lipoxygenase. The epithelial 12-lipoxygenase is antigenically related to the leukocyte 12-lipoxygenase but is biochemically distinct from platelet and leukocyte forms of the enzyme, in that it is more efficient at metabolizing a wider array of fatty acid substrates. We have suggested that this lipoxygenase heterogeneity may provide a basis for different functional roles for the enzyme in different cell types. In addition, animal epithelial 12-lipoxygenase and human epithelial 15-lipoxygenase are antigenically related and have similar but distinct distributions in the lung. Our findings might suggest that the species diversity for epithelial lipoxygenases represents molecular divergence within a family of closely related genes with perhaps closely related functions.