Coexistence of a novel SRBD1-ALK, ALK-CACNA1D double-fusion in a lung adenocarcinoma patient and response to alectinib: A case report.

A Chinese male patient with advanced lung adenocarcinoma experienced disease progression one and a half years after receiving first-line immunochemotherapy. The second biopsy was performed and tissue immunohistochemistry revealed Anaplastic lymphoma kinase (ALK) expression in the cytoplasm of tumor cells, so he began to receive Alectinib treatment. Then the next generation sequencing found double fusion variants of S1 RNA binding domain 1 (SRBD1)- ALK and ALK- Calcium voltage-gated channel subunit alpha1 D (CACNA1D). After continuous Alectinib treatment for 7 months, almost complete response (CR) was achieved. The patient is currently taking Alectinib for 13 months, the condition is stable, and is waiting for the next cycle of efficacy evaluation.

[Cytology Smears of Rapid On-site Evaluation as Supplemental Material 
for Molecular Testing of Non-small Cell Lung Cancer].

BACKGROUND: The thoracic small biopsy sampling procedure including transbronchial forceps lung biopsy (TBLB) and endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) can be accompanied by rapid on-site evaluation (ROSE) of sample material to provide immediate feedback for the proceduralist. The present study aims to investigate the supplemental effect of ROSE smear samples for lung cancer molecular test. METHODS: In a retrospective study, 308 patients admitted to our hospital from August 2020 to December 2022 undergoing diagnostic TBLB and EBUS-TBNA with ROSE and subsequently diagnosed as non-small cell lung cancer (NSCLC) were analyzed. The matched formalin-fixed paraffin-embedding (FFPE) tissue section and ROSE smears for tumor cellularity were compared. DNA yields of smears were determined. Real-time polymerase chain reaction (PCR) and next-generation sequencing (NGS) were performed on adequate smear samples. RESULTS: ROSE smear samples were enriched in tumor cells. Among 308 biopsy samples, 78 cases (25.3%) exhibited inadequate FFPE tissue sections, whereas 44 cases (14.3%) yielded adequate smear samples. Somatic mutations detected in the FFPE tissue section samples were also detected in the matching adequate smear sample. CONCLUSIONS: ROSE smear samples of the thoracic small biopsies are beneficial supplemental materials for ancillary testing of lung cancer. Combined use of cytology smear samples with traditional FFPE section samples can enhance the detection rate of informative mutations in patients with advanced NSCLC. We recommend that the laboratory could further evaluate the ROSE cell smears of the patient when FFPE tissue sections are inadequate, and that adequate cell smears can be used as a supplemental source for the molecular testing of NSCLC.

Comparative analysis of genomic profiles between tissue-based and plasma-based next-generation sequencing in patients with non-small cell lung cancer.

OBJECTIVES: Genotype-guided personalized therapy has become an essential part of routine clinical care in non-small cell lung cancer (NSCLC) patients. However, small tissue specimens often yield inadequate molecular testing material. Plasma ctDNA-based liquid biopsy is an increasingly common non-invasive alternative to tissue biopsy. This study examined the similarities and differences in the molecular profiling of tissue and plasma samples to provide insight into sample selection in clinical practice. MATERIALS AND METHODS: Sequencing data from 190 NSCLC patients who underwent concurrent tissue-based next-generation sequencing (tissue-NGS) and plasma-based NGS (plasma-NGS) using a 168-gene panel were analyzed. RESULTS: Tissue-NGS identified genomic alterations in 97.4% (185/190) of the enrolled patients and plasma-NGS identified genomic alterations in 72.1% (137/190) of the enrolled patients. Considering all NSCLC guideline-recommended biomarkers in the entire cohort of 190 cases, 81 patients had positive concordant mutations detected in both tissue and plasma samples, while 69 patients had no predefined alterations detected in either tissue or plasma samples. Additional mutations were found in the tissues of 34 patients and the plasma of six patients. The overall concordance rate between tissue and plasma samples was 78.9% (150/190). The tissue-NGS and plasma-NGS sensitivities were 95.0% and 71.9%, respectively. In the 137 patients with detectable ctDNA in plasma samples, the concordance rate between tissue and plasma samples reached 91.2%, and the sensitivity of plasma-NGS reached 93.5%. CONCLUSION: Our findings indicate that plasma-NGS is less capable of detecting genetic alterations than tissue-NGS, especially for copy number variations and gene fusions. Tissue-NGS remains the preferred method for evaluating the molecular profile of NSCLC patients when tumor tissue is available. We suggest that the concurrent use of liquid biopsy and tissue biopsy is the optimal approach in clinical practice; alternatively, plasma can be used as substitute material when tissue is unavailable.

Cell pellet from fixative medium of transbronchial lung biopsy sample improves lung cancer ancillary test.

OBJECTIVES: Lung cancer tissue obtained using small biopsies are relatively fragile, leaving behind some tiny tissue fragments or cell clusters in the fixative medium that are difficult to collect for processing as a paraffin-embedded tissue block. Usually, the cellular component of the residual fixative medium is discarded as medical waste as per routine laboratory protocol. No protocol exists for utilizing the cellular component of the residual fixative medium after processing the tissue blocks to improve lung cancer ancillary testing. This study aimed to undercover the potential value of these samples for lung cancer diagnosis and targeted therapy development. MATERIALS AND METHODS: A protocol was developed for cell pellet sample collection from the residual fixative medium of a transbronchial forceps lung biopsy sample. Tumour cell number and fraction in a paired cell pellet and matching formalin-fixed paraffin-embedded tissue section were evaluated from 324 non-smallcell lung carcinoma (NSCLC) cases. We defined the adequacy of the cell pellet for molecular analysis as ≥ 200 tumour cells and ≥ 10 % tumour cells. Real-time polymerase chain reaction and next-generation sequencing were performed on adequate cell pellet samples. RESULTS: We discovered that the fixative medium of most transbronchial forceps lung biopsy samples was enriched in tumour cells. Among 324 biopsy samples, 70 (21.6%) exhibited inadequate formalin-fixed paraffin-embedded tissue sections, whereas 53 (75.7%) yielded adequate cell pellet samples. Somatic mutations detected in the formalin-fixed paraffin-embedded tissue section samples were also detected in the matching cell pellets. CONCLUSIONS: Cell pellets collected from the fixative medium of thoracic small biopsies are a beneficial supplemental material for ancillary testing. Combined use of cell pellets with traditional tissue-based samples can enhance the detection rate of informative mutations in patients with advanced NSCLC.

Enhanced ultrasound-guided versus non-enhanced ultrasound-guided percutaneous needle biopsy in tissue cellularity of lung malignancies: a propensity score matched study.

Background: Though ultrasound-guided percutaneous lung needle biopsy (US-PLNB) is a first-line small biopsy method for peripheral lung lesions, quality of cellularity in specimens obtained via US-PLNB is uncertain. This study investigated the accuracy, sensitivity, and cellularity of US-PLNB. It examined the ability of contrast-enhanced ultrasound (CEUS) to improve the effectiveness of US-PLNB. Methods: We retrospectively analyzed all data of patients with subpleural lung lesions who underwent US-PLNB. The cellularity of US-PLNB from malignant lesions included the tumor cell number and proportion. The definition of high-quality cellularity (HQC) was concurrently achieving a tumor cell number ≥400 and a proportion ≥20%. The sensitivity, the actual numbers of tumor cell number/proportion, and the rate of HQC were calculated and compared between the CEUS and non-enhanced US groups after propensity score matching (PSM) with subgroup analyses by lesion size (small lesion ≤30 mm and large lesion >30 mm). Results: A total of 345 patients undergoing 345 US-PLNBs were evaluated, with 3.7±1.1 of punctures on average. There were 201 malignant and 144 benign lesions with a mean size of 43.8±24.1 mm. Among the 201 malignant lesions, 124 cases underwent CEUS and 77 underwent non-enhanced US. The quantity of tumor cells, the proportion of tumor cells, and the rate of HQC in 201 cases of US-PLNB from malignant lesions were 2,862.1±2,288.0, 44.6%±24.5%, and 82.1% [95% confidence interval (CI): 76.6% to 87.1%], respectively. The quantity of tumor cells, the proportion of tumor cells, and rate of HQC were significantly higher in the CEUS group than that in the non-enhanced US group, both in the analysis of overall malignant lesions and in large malignant lesions (all P<0.05). Conclusions: The US-PLNB has high sensitivity and thereby obtains HQC samples for subpleural lung malignant lesions. The CEUS helps improve the rate of HQC and tissue cellularity of lung malignancies.

Proposed clinical phases for the improvement of personalized treatment of checkpoint inhibitor-related pneumonitis.

Background: Checkpoint inhibitor-related pneumonitis (CIP) is a lethal immune-related adverse event. However, the development process of CIP, which may provide insight into more effective management, has not been extensively examined. Methods: We conducted a multicenter retrospective analysis of 56 patients who developed CIP. Clinical characteristics, radiological features, histologic features, and laboratory tests were analyzed. After a comprehensive analysis, we proposed acute, subacute, and chronic phases of CIP and summarized each phase's characteristics. Results: There were 51 patients in the acute phase, 22 in the subacute phase, and 11 in the chronic phase. The median interval time from the beginning of CIP to the different phases was calculated (acute phase: ≤4.9 weeks; subacute phase: 4.9~13.1 weeks; and chronic phase: ≥13.1 weeks). The symptoms relieved from the acute phase to the chronic phase, and the CIP grade and Performance Status score decreased (P<0.05). The main change in radiologic features was the absorption of the lesions, and 3 (3/11) patients in the chronic phase had persistent traction bronchiectasis. For histologic features, most patients had acute fibrinous pneumonitis in the acute phase (5/8), and most had organizing pneumonia in the subacute phase (5/6). Other histologic changes advanced over time, with the lesions entering a state of fibrosis. Moreover, the levels of interleukin-6, interleukin-10 and high-sensitivity C-reactive protein (hsCRP) increased in the acute phase and decreased as CIP progressed (IL-6: 17.9 vs. 9.8 vs. 5.7, P=0.018; IL-10: 4.6 vs 3.0 vs. 2.0, P=0.041; hsCRP: 88.2 vs. 19.4 vs. 14.4, P=0.005). Conclusions: The general development process of CIP can be divided into acute, subacute, and chronic phases, upon which a better management strategy might be based devised.

Case Report: A Rare Case of Metachronous Multiple Primary Lung Cancers in a Patient With Successful Management by Switching From Anti-PD-1 Therapy to Anti-PD-L1 Therapy.

Without global standard diagnostic criteria, distinguishing multiple primary lung cancers (MPLCs) from intrapulmonary metastasis or histologic transformation has been a big challenge in clinical practice. Here, we described a rare case of metachronous adenocarcinoma and small cell lung cancer (SCLC) in a patient who developed drug resistance to pembrolizumab. Both DNA-sequencing and RNA-sequencing were performed on primary adenocarcinoma and resistant lesions. Through the comparison of primary adenocarcinoma and novel lesion mutation profiles, along with bioinformatic estimation of immune proportion by using RNA sequence data, we revealed the origin and tumor microenvironment of the two lesions. No shared mutations were detected between lung adenocarcinoma (LUAD) and SCLC from the same patient, suggesting these two lesions might be from separate primary lung cancers. Compared to LUAD, SCLC showed a relatively cold microenvironment, including negative PD-L1. The patient obtained durable clinical benefits upon treatment with atezolizumab, without experiencing immune-related adverse events. Disease progression should be monitored with prompt re-biopsy and molecular profiling to spot a potential histologic change and to shed light on therapeutic alternatives. The use of atezolizumab, either alone or in combination with other agents, may be a potential therapeutic strategy for patients with both LUAD and SCLC.

[Analysis of the Relationship Between the Quality of Small Biopsy Specimens of 
Non-small Cell Lung Cancer and the Mutation Rate of EGFR Gene].

BACKGROUND: Epidermal growth factor receptor (EGFR) is the gene with the highest mutation rate in non-small cell lung cancer (NSCLC) patients, and the accurate evaluation of its mutational status can facilitate patients receiving targeted drug therapy and thereby prolong patients' survival. The gene testing platform has adequacy requirements for the specimen quality in order to obtain accurate examination results. It has been reported that the number and proportion of tumor cells in samples will affect the detection rate of EGFR gene mutation. The present study aims to analyze the relationship between the quality of small biopsy specimens of NSCLC and the mutation rate of EGFR gene with amplification refractory mutation system (ARSM) test. METHODS: After collecting the clinical characteristics of 299 cases small biopsy of lung adenocarcinoma, DNA concentration of the specimens and the mutational status of EGFR gene, the number and proportion of tumor cells in HE stained sections evaluated using light microscopy, the relationship between specimen quality and the mutation rate of EGFR gene were analyzed. RESULTS: The mutation rates of EGFR for the groups with tumor cell number ≤500 and >500 were 40.7% (11/27) and 43.8% (119/272) respectively, without significant difference (P=0.764). The mutation rates for the groups with DNA concentration ≤20.4 ng/µL and >20.4 ng/µL were 42.7% (64/150) and 44.3% (66/149) respectively, without significant difference (P=0.776). The mutation rates for the groups with tumor cells proportion ≤30% and >30% were 29.4% (20/68) and 47.6% (110/231) respectively, demonstrating significant difference (P=0.008). Multivariate Logistic analysis showed that male, thyroid transcription factor-1 (TTF-1) negative, smoking history and tumor cell proportion less than 30% were main factors that contributes to the low detection rate of EGFR gene mutation. CONCLUSIONS: After meeting the minimum requirements for detection, the EGFR mutation rate is affected by the proportion of tumor cells in the sample. Therefore, it is necessary to re-evaluate the tumor cell proportion in the last section after the genetic test section. For samples with lower tumor cell proportion, enriching tumor cells through microdissection and other methods is recommended for a more accurate detection result. For specimens that cannot be enriched with tumor cells, circulating tumor DNA (ctDNA) test can be performed as a supplement. If the result is still negative, another biopsy should be considered to obtain enough tumor specimens for molecular testing.

Case Report: Neoadjuvant and Adjuvant Crizotinib Targeted Therapy in Stage IIIA-N2 ALK-Positive Non-Small-Cell Lung Cancer.

The treatment of anaplastic lymphoma kinase (ALK)-positive locally advanced non-small-cell lung cancer (NSCLC) is challenging because there is no randomized controlled trial has been reported. The value of neoadjuvant and adjuvant targeted therapy remains unclear. Herein, we show that systemic treatment with ALK inhibitor crizotinib before surgery can provide the potential to cure the initially inoperable tumor. A 27-year-old man was diagnosed with a stage IIIAcT3N2M0 (7thUICC/AJCC) upper left lung adenocarcinoma harboring EML4-ALK fusion gene. Clinically, the patient had a large primary lesion adjacent to the pericardium and regional lymph node metastasis at the ipsilateral mediastinum. Poor tumor response was observed after 3 cycles of chemotherapy (gemcitabine plus cisplatin), and upon multidisciplinary discussion, the patient was started with 250 mg crizotinib twice daily. Successive clinical examinations showed a progressive reduction of the lesions. After 2 months of therapy, the patient was downstaged to cT2aN2M0, then video-assisted thoracic surgery was performed and the final histopathological stage was ypT2aN2M0. The treatment with crizotinib (250 mg, qd) was continued more than 30 months post surgery and stopped until intracranial oligometastasis. The patient's overall survival (OS) time is 68 months at last follow-up. This case presented here supports the use of neoadjuvant and adjuvant treatment with ALK inhibitors in ALK positive locally advanced NSCLC.

Pulmonary capillary hemangiomatosis in Chinese patients without EIF2AK4 mutations.

BACKGROUND: Pulmonary capillary hemangiomatosis (PCH) is a very rare and refractory pulmonary vascular disease that causes pulmonary hypertension. Differentiation of PCH from idiopathic pulmonary arterial hypertension (iPAH) is essential because treatment and prognosis can vary greatly between these two diseases. CASE PRESENTATION: A 20-year-old female and a 33-year-old male both presented with progressive exertional dyspnea and cough. High-resolution computed tomography (HRCT) showed bilateral, diffuse, ill-defined centrilobular nodules of ground-glass opacity, without subpleural thickened septal lines or mediastinal lymphadenopathy. Both cases showed clinical and imaging features characteristic of pulmonary veno-occlusive disease (PVOD) or PCH. The entire EIF2AK4 coding sequence was detected with Sanger sequencing, and no pathogenic EIF2AK4 mutations were identified in either case. Video-assisted thoracoscopic surgery (VATS) was safely performed in both cases, and histopathological examinations of biopsies showed that both patients had PCH. CONCLUSION: Two patients presented with clinical and imaging characteristics suspicious for PVOD/PCH. Despite having no pathogenic EIF2AK4 mutations, both were diagnosed with PCH by VATS lung biopsies. The diagnostic distinction of PCH is important to prompt timely evaluations of patients who may need lung transplantations.

[Investigation on the Possibility of EGFR Mutation Testing on DNA Extracted from Fixation Liquid of Lung Cancer Biopsy].

BACKGROUND: Epidermal growth factor receptor (EGFR) mutation is the most common gene mutation in patients with non-small cell lung cancer (NSCLC). Many international guidelines are recommended to detected the EGFR mutation before the treatment of advanced non-small cell lung cancer. To investigate the possibility of EGFR mutation testing on DNA extracted from fixation liquid of lung cancer biopsy. METHODS: Fixation liquid of lung cancer biopsy was collected and stored at -80 oC after centrifugal. DNA was extracted and EGFR gene mutation was detected by ARMS. Compared with EGFR mutation status of paraffin-embedded tissues, the consistency, the sensitivity and specificity of EGFR mutation testing were analyzed. RESULTS: Among the 28 cases of EGFR mutation positive and 20 cases of EGFR mutation negative previously tested on paraffin-embedded tissue by clinic test, 20 cases with EGFR mutation positive and 20 cases with negative were detected by matched fixation liquid of lung cancer biopsy, respectively. The sensitivity and specificity were 71.4% and 100%. Moreover, 52 paraffin-embedded tissues and matched fixation liquid of lung cancer biopsy with unknown EGFR mutation status were detected, and the EGFR mutation positive rate were 36.5% and 28.8% respectively. The sensitivity and specificity of fixation liquid of lung cancer biopsy were 78.9% and 100.0%. CONCLUSIONS: Extracting the DNA from fixation liquid of lung cancer biopsy may be a kind of feasible way to detect EGFR mutation.

PAK4 Phosphorylates Fumarase and Blocks TGFß-Induced Cell Growth Arrest in Lung Cancer Cells.

The metabolic activity of fumarase (FH) participates in gene transcription linking to tumor cell growth. However, whether this effect is implicated in lung cancer remains unclear. Here, we show TGFß induces p38-mediated FH phosphorylation at Thr 90, which leads to a FH/CSL (also known as RBP-Jκ)/p53 complex formation and FH accumulation at p21 promoter under concomitant activation of Notch signaling; in turn, FH inhibits histone H3 Lys 36 demethylation and thereby promotes p21 transcription and cell growth arrest. In addition, FH is massively phosphorylated at the Ser 46 by PAK4 in non-small cell lung cancer (NSCLC) cells, and PAK4-phosphorylated FH binds to 14-3-3, resulting in cytosolic detention of FH and prohibition of FH/CSL/p53 complex formation. Physiologically, FH Ser 46 phosphorylation promotes tumorigenesis through its suppressive effect on FH Thr 90 phosphorylation-mediated cell growth arrest in NSCLC cells and correlates with poor prognosis in patients with lung cancer. Our findings uncover an uncharacterized mechanism underlying the local effect of FH on TGFß-induced gene transcription, on which the inhibitory effect from PAK4 promotes tumorigenesis in lung cancer. SIGNIFICANCE: Fumarase counteracts CSL via its metabolic activity to facilitate TGFß-induced cell growth arrest, an effect largely blocked by PAK4-mediated phosphorylation of fumarase.

Correlations between computed tomography and positron emission tomography/computed tomography findings and pathology in 6 cases of pulmonary epithelioid angiosarcoma.

Previous studies on primary pulmonary epithelioid angiosarcoma (PEA) have been mostly clinical or pathological case reports. We here summarize findings from computed tomography (CT) and positron emission tomography/computed tomography (PET/CT) analyses of PEA to improve the diagnosis and differentiation of this rare tumor.We conducted a retrospective analysis of the clinical findings, radiological imaging, and pathological findings of 6 cases of primary PEA confirmed by surgery, biopsy, and pathology. All cases were evaluated by CT and x-ray prior to surgery, and 2 cases were further examined by PET/CT.CT images indicated maximum tumor diameters of 2.4 to 9.8 cm and inhomogeneous density, with 1 case exhibiting nodular calcification. Contrast-enhanced CT revealed inhomogeneous enhancement with visible necrosis in all 6 cases, while 3 cases had hilar and mediastinal lymph node metastasis. Five cases displayed extensive tumor involvement with extension into the chest wall, mild-to-moderate levels of pleural effusion, and varying degrees of volume loss in the corresponding hemithorax. One case had limited pleural thickening and invasion. Preoperative PET/CT of 1 case revealed abnormal fluorine-18 fluorodeoxyglucose (F-FDG) uptake by the tumor and multiple enlarged right hilar and mediastinal lymph nodes, right diffuse pleural thickening, and systemic multiple bone metastasis. In the other case, PET/CT scan at 7 months after surgery revealed pleural thickening and mediastinal lymph nodes with increased F-FDG uptake on the surgical side. Immunohistochemistry analyses determined that all 6 tumors were positive for CD34, CD31, ERG, and vimentin.CT and PET/CT findings reveal that malignant characteristics, including extensive pleural thickening, invasion and metastasis, and pleural effusion, are common in PEA. Imaging data are only supportive; therefore, the final diagnosis should be based on pathology and immunohistochemistry analyses.

Cecal Endometriosis With Intestinal Metaplasia Misdiagnosed as Neoplasm of the Cecum by Intraoperative Histological Examination.

Appendiceal or cecal endometriosis with intestinal metaplasia is uncommon and may mimic mucinous tumors of the appendix. A 50-year-old woman was found incidentally to have an ileocecal lesion. In the intraoperative histological examination, a diagnosis of neoplasm of the cecum was made predominantly based on mucin extrusion with scattered lining mucinous epithelium. However, postoperative histological diagnosis of the lesion was cecal endometriosis with intestinal metaplasia as determined by thoroughly microscopic inspection and the presence of typical endometrial glands with surrounding endometrial-type stroma. There was no evidence of recurrence and pseudomyxoma peritonei after 1 year of follow-up. Overinterpretation of cytological atypia or mucin extrusion in endometriosis may lead to inappropriate surgical management. Therefore, in any ileocecal or appendiceal lesions with mucinous epithelia and mucin extrusions, removal of sufficient tissue from different portions of the lesion is essential for surgeons and pathologists to make a precise diagnosis in the intraoperative histological examination.

Reverse the Resistance to PARP Inhibitors.

One of the DNA repair machineries is activated by Poly (ADP-ribose) Polymerase (PARP) enzyme. Particularly, this enzyme is involved in repair of damages to single-strand DNA, thus decreasing the chances of generating double-strand breaks in the genome. Therefore, the concept to block PARP enzymes by PARP inhibitor (PARPi) was appreciated in cancer treatment. PARPi has been designed and tested for many years and became a potential supplement for the conventional chemotherapy. However, increasing evidence indicates the appearance of the resistance to this treatment. Specifically, cancer cells may acquire new mutations or events that overcome the positive effect of these drugs. This paper describes several molecular mechanisms of PARPi resistance which were reported most recently, and summarizes some strategies to reverse this type of drug resistance.

Ganetespib overcomes resistance to PARP inhibitors in breast cancer by targeting core proteins in the DNA repair machinery.

DNA damage repair plays essential roles in drug resistance, especially resistance to Poly (ADP-ribose) polymerase (PARP) inhibitors in the clinic. A subset of DNA repair proteins such as Breast cancer gene 1 (BRCA1), BRCA2 and RecA homolog (RAD51) are client proteins of heat shock protein 90 (Hsp90). Clearance of these DNA repair proteins by inhibition of Hsp90 is a promising strategy for overcoming resistance to PARP inhibitors. Here we report the pharmacological analysis of the highly potent second-generation Hsp90 inhibitor, ganetespib. Methods Nuclear BRCA1, BRCA2, and RAD51 expression in breast cancer cells were detected by subcellular fractionation and western blot analysis. Formation of nuclear RAD51 and γ-H2AX foci was analyzed by immunofluorescent staining. The cytotoxicity of ganetespib and ABT-888 in breast cancer cells were evaluated by cell proliferation, colony survival, and apoptosis assay. To investigate the efficacy of this therapy in vivo, SCID mice bearing MCF7 xenografts were treated with ganetespib and ABT-888, both as single agents and in combination. Results Ganetespib significantly destabilized nuclear BRCA1, BRCA2, and RAD51, and efficiently disrupted homologous recombination-mediated DNA double-strand break repair in breast cancer cells. The synergistic antitumor effects of ganetespib and the PARP inhibitor, ABT-888 were observed, and concurrent treatment with both inhibitors synergistically inhibited xenograft tumor growth. Importantly, the combined treatment was well tolerated, without significant loss of body weight or major histological changes in the breast cancer xenograft model. Conclusion These data provide a novel strategy for the treatment of breast cancer with wild type BRCA1 using combination therapy targeting Hsp90 to overcome resistance to PARP inhibitors.

Coexistence of p16/CDKN2A homozygous deletions and activating EGFR mutations in lung adenocarcinoma patients signifies a poor response to EGFR-TKIs.

OBJECTIVES: Activating mutations in the epidermal growth factor receptor (EGFR) are strongly predictive of EGFR-tyrosine kinase inhibitor (TKI) activity in non-small cell lung cancer (NSCLC). However, primary resistance to EGFR-TKIs occurs in approximately 20-30% of NSCLC patients with EGFR mutations. The goal of this study was to determine whether p16/CDKN2A homozygous deletion (HD) is associated with primary resistance to EGFR-TKIs in lung adenocarcinoma patients with EGFR activating mutations. METHODS: We investigated 127 patients with stage IIIB or IV lung adenocarcinoma harboring activating EGFR mutations, and who had received EGFR-TKIs as first-line therapy. Dual-color fluorescence in situ hybridization for p16/CDKN2A and chromosome 9 was performed in tumor biopsy samples obtained before initiation of EGFR-TKI treatment. RESULTS: p16/CDKN2A HD was detected in 24.4% (31/127) of patients, and the overall response rate in patients with and without this mutation was 48.4% and 78.1%, respectively (P=0.0027). The median progression-free survival was 5.3 months (95% confidence interval [CI]: 4.582-6.018) for patients with p16/CDKN2A HD and 10.5 months (95% CI: 9.365-11.635 months) for patients without the mutation (P=0.001). No correlations between p16/CDKN2A HD and patient characteristics including gender, age, smoking history, EGFR mutation type, tumor-node-metastasis stage, and performance status were found. CONCLUSIONS: Our study demonstrates that the coexistence of p16/CDKN2A HDs and activating EGFR mutations in lung adenocarcinoma patients signifies a poor response to EGFR-TKI therapy.

Validation of human small airway measurements using endobronchial optical coherence tomography.

BACKGROUND: Small airway remodeling is the cardinal feature underlying chronic airway diseases. There is no modality which identifies small airway pathological changes, which is crucial for early diagnosis, efficacy and prognostic assessment. OBJECTIVE: To evaluate the usefulness of endobronchial optical coherence tomography (EB-OCT) in assessing small airways morphology in vivo. METHODS: Twelve patients with pulmonary nodules scheduled for lung resection underwent spirometry, multi-detector computed tomography (MDCT) and EB-OCT. We measured D(mean) (mean luminal diameter), Ai (inner luminal area), Aw (airway wall area) and Aw% [Aw/(Ai + Aw) × 100%] from the 3rd to 5th generation bronchi of RB9 segment by MDCT. D(mean), Ai, Aw and Aw% from the 3rd to 9th generation bronchi of RB9 segment were measured by EB-OCT and histology. Correlations of these parameters, measured by three different methods, were evaluated. We recruited 4 COPD patients to determine if EB-OCT could identify peripheral airway remodeling. RESULTS: The 4 parameters, measured by CT and EB-OCT, correlated significantly [D(mean) (r = 0.991), Ai (r = 0.997), Aw (r = 0.997), Aw% (r = 0.991), all P < 0.01]. Significant correlation were found for these parameters, measured by histology and EB-OCT, from the 3rd to 5th generation bronchi [D(mean) (r = 0.989), Ai (r = 0.997), Aw (r = 0.999), Aw% (r = 0.988), all P < 0.01], and from the 6th to 9th generation bronchi [D(mean) (r = 0.979), Ai (r = 0.997), Aw (r = 0.994) and Aw% (r = 0.988), all P < 0.01]. Significant small airways morphological abnormalities were observed in COPD patients. CONCLUSIONS: EB-OCT, a minimally invasive imaging modality with high-resolution, is useful and clinically practical for assessing proximal and distal airways of human compared with CT and histology.

Pulmonary epithelioid inflammatory myofibroblastic sarcoma with multiple bone metastases: case report and review of literature.

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare variant of inflammatory myofibroblastic tumor with distinctive morphological features and malignant clinical behavior. Only a few such cases have been described in the literature. We report here a case of unusual pulmonary EIMS with multiple bone metastases. A 21-year-old Chinese male patient presented with complaints of general fatigue and rapid weight loss, and a huge tumor arising in the left lower lobe of lung was detected by chest computed tomography. The mass of lung was totally resected. Microscopically, the tumor cells were rounded and epithelioid in shape. Myxoid stroma and inflammatory infiltration was also present. The tumor cells were immunopositive to anaplastic lymphoma kinase (ALK) in smooth cytoplasmic pattern. Fluorescence in situ hybridization (FISH) assay revealed the presence of rearrangement of ALK gene. Three months after lung surgery, there were multiple bone metastases and intraspinal mass found by positron emission tomography. The second surgical treatment was performed to remove the intraspinal lesion. The histological and immunohistochemical features of intraspinal mass were similar to those of pulmonary tumor. The diagnosis of pulmonary EIMS with multiple bone metastases was made. To the best of our knowledge, it may be the first case of an EIMS arising in lung. Awareness of EIMS in respiratory tract and its distinctive features is important for pathologists to avoid a diagnostic pitfall caused by histologic similarities to other ALK-positive tumors. ALK inhibitor is a promising treatment for this aggressive tumor regardless of its potential acquired resistance.