Aligning tumor mutational burden (TMB) quantification across diagnostic platforms: phase II of the Friends of Cancer Research TMB Harmonization Project.

BACKGROUND: Tumor mutational burden (TMB) measurements aid in identifying patients who are likely to benefit from immunotherapy; however, there is empirical variability across panel assays and factors contributing to this variability have not been comprehensively investigated. Identifying sources of variability can help facilitate comparability across different panel assays, which may aid in broader adoption of panel assays and development of clinical applications. MATERIALS AND METHODS: Twenty-nine tumor samples and 10 human-derived cell lines were processed and distributed to 16 laboratories; each used their own bioinformatics pipelines to calculate TMB and compare to whole exome results. Additionally, theoretical positive percent agreement (PPA) and negative percent agreement (NPA) of TMB were estimated. The impact of filtering pathogenic and germline variants on TMB estimates was assessed. Calibration curves specific to each panel assay were developed to facilitate translation of panel TMB values to whole exome sequencing (WES) TMB values. RESULTS: Panel sizes >667 Kb are necessary to maintain adequate PPA and NPA for calling TMB high versus TMB low across the range of cut-offs used in practice. Failure to filter out pathogenic variants when estimating panel TMB resulted in overestimating TMB relative to WES for all assays. Filtering out potential germline variants at >0% population minor allele frequency resulted in the strongest correlation to WES TMB. Application of a calibration approach derived from The Cancer Genome Atlas data, tailored to each panel assay, reduced the spread of panel TMB values around the WES TMB as reflected in lower root mean squared error (RMSE) for 26/29 (90%) of the clinical samples. CONCLUSIONS: Estimation of TMB varies across different panels, with panel size, gene content, and bioinformatics pipelines contributing to empirical variability. Statistical calibration can achieve more consistent results across panels and allows for comparison of TMB values across various panel assays. To promote reproducibility and comparability across assays, a software tool was developed and made publicly available.

[IgG4-related disease: what do we know after 20 years].

IgG4-related disease is immunomediated fibroinflammatory condition, characterized by tumefective lesions in different organs with distinctive pathomorphological features and IgG4 hypersecretion in serum and tissues in the majority of patients. IgG4-RD has been established as a separate clinical in the early 2000s. In the review we focus on the evolution of views on ethiopathogenesis of the disease, therapeutic and diagnostic options and classification of the disease.

Tumor mutational burden is predictive of response to immune checkpoint inhibitors in MSI-high metastatic colorectal cancer.

BACKGROUND: Microsatellite instability (MSI) is a biomarker for response to immune checkpoint inhibitors (ICPIs). PD-1 inhibitors in metastatic colorectal carcinoma (mCRC) with MSI-high (MSI-H) have demonstrated a high disease control rate and favorable progression-free survival (PFS); however, reported response rates to pembrolizumab and nivolumab are variable and often <50%, suggesting that additional predictive biomarkers are needed. METHODS: Clinicopathologic data were collected from patients with MSI-H mCRC confirmed by hybrid capture-based next-generation sequencing (NGS) treated with PD-1/L1 inhibitors at five institutes. Tumor mutational burden (TMB) was determined on 0.8-1.1 Mb of sequenced DNA and reported as mutations/Mb. Potential biomarkers of response and time to progression were analyzed by univariate and multivariate analyses. Once TMB was confirmed as a predictive biomarker, a larger dataset of 18 140 unique CRC patients was analyzed to define the relevance of the identified TMB cut-point. RESULTS: A total of 22 patients were treated with PD-1/L1 inhibitors including 19 with pembrolizumab monotherapy. Among tested variables, TMB showed the strongest association with objective response (OR; P < 0.001) and PFS, by univariate (P < 0.001) and multivariate analysis (P < 0.01). Using log-rank statistics, the optimal predictive cut-point for TMB was estimated between 37 and 41 mutations/Mb. All 13 TMBhigh cases responded, while 6/9 TMBlow cases had progressive disease. The median PFS for TMBhigh has not been reached (median follow-up >18 months) while the median PFS for TMBlow was 2 months. A TMB of 37.4 mutations/Mb in a large MSI-H mCRC population (821/18, 140 cases; 4.5%) evaluated by NGS corresponded to the 35th percentile cut-point. CONCLUSIONS: TMB appears to be an important independent biomarker within MSI-H mCRC to stratify patients for likelihood of response to ICPIs. If validated in prospective studies, TMB may play an important role in guiding the sequencing and/or combinations of ICPIs in MSI-H mCRC.

Loss of function of NF1 is a mechanism of acquired resistance to endocrine therapy in lobular breast cancer.

Background: Invasive lobular carcinoma (ILC) as a disease entity distinct from invasive ductal carcinoma (IDC) has merited focused studies of the genomic landscape, but those to date are largely limited to the assessment of early-stage cancers. Given that genomic alterations develop as acquired resistance to endocrine therapy, studies on refractory ILC are needed. Patients and methods: Tissue from 336 primary-enriched, breast-biopsied ILC and 485 estrogen receptor (ER)-positive IDC and metastatic biopsy specimens from 180 ILC and 191 ER-positive IDC patients was assayed with hybrid-capture-based comprehensive genomic profiling for short variant, indel, copy number variants, and rearrangements in up to 395 cancer-related genes. Results: Whereas ESR1 alterations are enriched in the metastases of both ILC and IDC compared with breast specimens, NF1 alterations are enriched only in ILC metastases (mILC). NF1 alterations are predominantly under loss of heterozygosity (11/14, 79%), are mutually exclusive with ESR1 mutations [odds ratio = 0.24, P < 0.027] and are frequently polyclonal in ctDNA assays. Assessment of paired specimens shows that NF1 alterations arise in the setting of acquired resistance. An in vitro model of CDH1 mutated ER-positive breast cancer demonstrates that NF1 knockdown confers a growth advantage in the presence of 4-hydroxy tamoxifen. Our study further identified a significant increase in tumor mutational burden (TMB) in mILCs relative to breast ILCs or metastatic IDCs (8.9% >20 mutations/mb; P < 0.001). Most TMB-high mILCs harbor an APOBEC trinucleotide signature (14/16; 88%). Conclusions: This study identifies alteration of NF1 as enriched specifically in mILC. Mutual exclusivity with ESR1 alterations, polyclonality in relapsed ctDNA, and de novo acquisition suggest a role for NF1 loss in endocrine therapy resistance. Since NF1 loss leads to RAS/RAF kinase activation, patients may benefit from a matched inhibitor. Moreover, for an independent subset of mILC, TMB was elevated relative to breast ILC, suggesting possible benefit from immune checkpoint inhibitors.

[Clinical and laboratory characteristics of IgG4-realated disease and its diagnostic algorithm].

AIM: to propose diagnostic algorithm of IgG4-related disease (IgG4-RD). MATERIALS AND METHODS: One center retrospective research. 52 pts with IgG4-RD were included. The diagnosis was proved histologically and immunohistochemically. 48 out of 52 pts received treatment. Treatment included one of the following schemes (along with low oral glucocorticoids): rituximab monotherapy, cyclophosphamide monotherapy or their combination. RESULTS: The mean age was 47.4±5.9 years, the mean age of the disease onset was 43.9±16.0 years. Median time before the diagnosis was 24 months. The most often sites of IgG4-RD were lacrimal (63.5%), salivary (46.2%) glands, lungs (48%), lymph nodes (34.6%) and retroperitoneum (17.3%). In clinical picture the leading complain was organ enlargement, but not its dysfunction. Pain was characteristic for retroperitoneum localization. In 56.8% of pts with IgG4-related syalo - and/or dacryoadenitis there was association with ear - nose - throat organs affection. In 4 pts (7.7%) IgG4-RD was combined with some malignant disease, including MALT-lymphoma of lacrimal glands. Irreversible organ damage as an IgG4-RD outcome had 15.4% of pts. The main laboratory markers of IgG4-RD were ESR elevation (38.5%), blood eosinophilia (9.6%), immunological disturbances (serum total IgG and IgG4 elevation, IgE elevation, antinuclear antibodies, rheumatoid factor detection, hypocomplementemia). Serum IgG4 level >1.35 g/l was elevated in 88% of pts and correlated with the number of affected organs (Spearman correlation coefficient 0.39, Student's test, р=0.0056). Monoclonal serum secretion and B-cell clonality in the tissue was detected in 4 (23.5%) out of 17 pts, but not all of them had both signs. CONCLUSION: Based on the analysis of clinical and laboratory characteristics of IgG4-RD a diagnostic algorithm was proposed that enhances the detection and examination of the patients with suspected IgG4-RD.

[The differential diagnosis of Erdheim-Chester disease and IgG4-related diseases].

The paper describes Russia's first diagnosed case of Erdheim--Chester disease (systemic histiocytosis) in a 65-year-old man who has been long treated for Ormond's disease (idiopathic retroperitoneal fibrosis). It also gives the data available in the literature on the pathogenetic components of these diseases and on the similarity of many clinical, laboratory, and morphological characteristics of these two immunoinflammatory diseases and covers the issues of their differential diagnosis. Invasive procedures with a careful morphological/immunomorphological examination of biopsy specimens obtained from affected tissues are shown to be necessary for accurate diagnosis.

[IgG4-related disease and clonal B-cell lymphoid proliferation: Description of two clinical cases and a review of literature].

IgG4-related disease (IgG4-RD) is a systemic immune-related disease that may involve the pancreas, liver, retroperitoneal space, biliary tract, salivary and lacrimal glands, eye socket, lung, and kidney. In term of pathomorphogenesis, it is a fibroinflammatory disease manifesting as a tumor-like lesion of organs, elevated serum IgG4 levels, and a morphofunctional substrate - the development of marked fibrosis and lymphoplasmacytic infiltration in the tissues with the high content of IgG4-positive plasma cells. The detection of a tumor-like nodule frequently leads to that the patients with IgG4-RD undergo major traumatic surgery for presumed cancer. At the same time, a number of investigations show the association of IgG4-RD with the development of cancer and lymphoproliferative diseases. The paper describes two clinical cases: Russia's first diagnosis of MALT lymphoma of the lacrimal gland, IgG4-positive and IgG4-RD with a rare onset with a destruction focus in the cervical vertebrae, multiple organ dysfunction, B-cell clonality in salivary gland tissue and PIgMκ secretion. It also reviews world literature on the development of lymphoproliferative diseases in the presence of IgG4-RD.

[IgG4-related salivary gland lesions]. / Svyazannye s IgG-4 porazheniya slyunnykh zhelez.

AIM: To provide the demographic, clinical, laboratory, radiological, morphological, and immunomorphological characteristics of IgG4-related sialoadenitis (IgG4-S), which allow the differential diagnosis with neuroendocrine, granulomatous, blood cancer lesions of the salivary gland (SG). SUBJECTS AND METHODS: In the period 2004 to 2014, IgG4-S was diagnosed in 32 (11%) out of 289 patients with significantly enlarged parotid and submandibular glands (PG and SMG). Only 4 (9%) patients had isolated IgG4-related disease (IgG4-D) whereas involvement of a few organs ran as an IgG4-SD systemic disease in 29 (91%) patients. RESULTS: There was a slight preponderance of women with a median onset age of 42 years. Enlargement of the SMG (52.7%), lesions of the nasal cavity and paranasal sinuses (37.2%), and enlargement of the lacrimal gland and orbital pseudotumors (31%) are the most common clinical manifestations at disease onset. A follow-up study indicated that along with involvements of SMG (97%), PG (72%), eye sockets (72%), nasal cavity and paranasal sinuses (56%), one third of the patients were found to have generalized lymphadenopathy, to frequently develop pulmonary, hepatic, pancreatic, renal injuries; and the disease ran within IgG4-SD. The laboratory manifestations were characterized by moderate eosinophilia and elevated blood IgE levels in one-third of the patients and by moderately higher erythrocyte sedimentation rate and hypergammaglobulinemia in 50%. The increased blood level of IgG (84%) and its subclass IgG4 (86.4%) is an indication for further verification of IgG4-D in patients with involvement of the major SG. Immunohistochemical examination, by measuring the concentration of IgG4-secreting plasma cells (PCs), and determination of B-cell clonality in biopsy specimens should be done to verify a diagnosis with IgG4-D. CONCLUSION: The determination of blood IgG4 (>2 g/l) in patients with considerably enlarged major SG may suggest the presence of IgG4-S. Minimally invasively incised PG and SMG biopsies with their subsequent morphological and immunomorphological examinations should be performed to make an accurate diagnosis. More than 40% of IgG4-secreting PCs detected in SG tissue is evidence to diagnose IgG4-D.

[Differential diagnosis of rheumatic diseases and blood cancers involving the nasal cavity and accessory sinuses].

AIM: To provide the clinical, laboratory, radiological, morphological, and immunomorphological signs that permit the differential diagnosis to be made in patients with involvement of the nasal cavity and accessory sinuses (NCAS). SUBJECTS AND METHODS: In the period 2009 to 2013, the Laboratory for Intensive Therapy for Rheumatic Diseases, V.A. Nasonova Research Institute of Rheumatology, Russian Academy of Medical Sciences, associated the disease onset with NCAS involvement in 39 (7.6%) of 512 examinees. NCAS involvement was present at disease onset in 100% of the patients with natural killer (NK) cell lymphoma (NK/T lymphoma), in 84.5% of those with Wegener granulomatosis (WG), in 29.5% of those with IgG4-related disease (IgG4-RD), and in 17.5% of those with sarcoidosis. Such an onset could be extremely rarely observed in histiocytosis. RESULTS: Despite the similar clinical manifestations, NCAS involvements in NK/T lymphoma of nasal type and WG at disease onset show clear differences in the laboratory and systemic manifestations of these diseases. The patients with lymphoma have no characteristic laboratory abnormalities at disease onset, except the 100% presence of Epstein-Barr virus (EBV) DNA in blood and, only as a tumor grows, fever appears and there are elevated C-reactive protein and lactate dehydrogenase levels and pronounced destructive changes in the facial bones with mandatory hard palate destruction; at the same time the signs of systemic involvement are virtually absent. The patients with WG at disease onset have fever, high erythrocyte sedimentation rate, elevated C-reactive level, significant anemia, leukocytosis and 90% are found to have anti-neutrophil cytoplasmic antibodies with the rapid development of systemic manifestations: involvements of the lung, kidney, and peripheral nervous system. Destructive changes in the facial bones are minimal and hard palate destructions are absent. The patients with IgG4-RD, sarcoidosis, and juvenile xanthogranuloma have similar clinical and laboratory manifestations in the absence of hemorrhagic nasal discharge, nasal septal perforation, and facial bone destruction, with the practically involvement of the salivary/lacrimal glands and orbital regions. A third of the patients are observed to have different allergic manifestations, moderate eosinophilia, and signs of autoimmune disorders (the presence of rheumatoid and antinuclear factors, hypergammaglobulinemia). Elevated serum IgG4 levels are characteristic of IgG4-RD. CONCLUSION: Blood anti-neutrophil cytoplasmic antibodies, EBV DNA, and IgG4 levels should be determined in all patients with NCAS involvement. Mini-invasive incision biopsies of the nasal mucosa, orbital regions, and major salivary glands should be done, by morphologically verifying the diagnosis of sarcoidosis, histiocytosis, and WG and by making an immunomorphological examination to diagnose NK/T lymphoma and IgG4-RD.

Genomic characterization of thymic epithelial tumors in a real-world dataset.

BACKGROUND: Thymic epithelial tumors (TETs) are rare neoplasms arising in the mediastinum, including thymic carcinomas and thymomas. Due to their rarity, little is known about the genomic profiles of TETs. Herein, we investigated the genomic characteristics of TETs evaluated in a large comprehensive genomic profiling database in a real-world setting. METHODS: We included data from two different cohorts: Foundation Medicine Inc. (FMI) in the United States and the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) in Japan. Samples profiled were examined for all classes of alterations in 253 genes targeted across all assays. Tumor mutational burden (TMB) and microsatellite instability (MSI) were also evaluated. RESULTS: A total of 794 patients were collected in our study, including 722 cases from FMI and 72 cases from C-CAT. In the FMI data, CDKN2A (39.9%), TP53 (30.2%) and CDKN2B (24.6%) were frequently altered in thymic carcinoma, versus TP53 (7.8%), DNMT3A (6.8%), and CDKN2A (5.8%) in thymoma. TMB-high (≥10 mutations/Mb) and MSI were present in 7.0% and 2.3% of thymic carcinomas, and 1.6% and 0.3% of thymomas, respectively. Within C-CAT data, CDKN2A (38.5%), TP53 (36.5%) and CDKN2B (30.8%) were also frequently altered in thymic carcinoma, while alterations of TSC1, SETD2 and LTK (20.0% each) were found in thymoma. CONCLUSIONS: To the best of our knowledge, this is the largest cohort in which genomic alterations, TMB and MSI status of TETs were investigated. Potential targets for treatment previously unbeknownst in TETs are identified in this study, entailing newfound opportunities to advance therapeutic development.

Baseline mutational profiles of patients with carcinoma of unknown primary origin enrolled in the CUPISCO study.

BACKGROUND: Patients with unfavorable carcinoma of unknown primary origin (CUP) have an extremely poor prognosis of ∼1 year or less, stressing the need for more tailored treatments, which are currently being tested in clinical trials. CUPISCO (NCT03498521) was a phase II randomized study of targeted therapy/cancer immunotherapy versus platinum-based chemotherapy in patients with previously untreated, unfavorable CUP, defined as per the European Society for Medical Oncology guidelines. We present a preliminary, descriptive molecular analysis of 464 patients with stringently diagnosed, unfavorable CUP enrolled in the CUPISCO study. MATERIALS AND METHODS: Genomic profiling was carried out on formalin-fixed, paraffin-embedded tissue to detect genomic alterations and assess tumor mutational burden and microsatellite instability. RESULTS: Overall, ∼32% of patients carried a potentially targetable genomic alteration, including PIK3CA, FGFR2, ERBB2, BRAFV600E, EGFR, MET, NTRK1, ROS1, and ALK. Using hierarchical clustering of co-mutational profiles, 10 clusters were identified with specific genomic alteration co-occurrences, with some mirroring defined tumor entities. CONCLUSIONS: Results reveal the molecular heterogeneity of patients with unfavorable CUP and suggest that genomic profiling may be used as part of informed decision-making to identify the potential primary tumor and targeted treatment options. Whether stringently diagnosed patients with unfavorable CUP benefit from targeted therapies in a similar manner to those with matched known primaries will be a key learning from CUPISCO.

HPV-positive clinically advanced squamous cell carcinoma of the urinary bladder (aBSCC): A comprehensive genomic profiling (CGP) study.

BACKGROUND: Advanced bladder squamous cell carcinoma (aBSCC) is an uncommon form of urinary bladder malignancy when compared with the much higher urothelial carcinoma incidence. We studied the genomic alteration (GA) landscape in a series of aBSCC based on the association with human papilloma virus (HPV) to determine if differences in GA would be observed between the positive and negative groups. METHODS: Using a hybrid capture-based FDA-approved CGP assay, a series of 171 aBSCC were sequenced to evaluate all classes of GA. Tumor mutational burden (TMB) was determined on up to 1.1 Mbp of sequenced DNA and microsatellite instability (MSI) was determined on up to 114 loci. Programmed cell death ligand -1 (PD-L1) expression was determined by IHC (Dako 22C3) with negative expression when PD-L1 was 0, lower expression of positivity set at 1 to 49%, and higher expression set at ≥50% expression. RESULTS: Overall, 11 (6.4%) of the aBSCC were found to harbor HPV sequences (10 HPV16 and 1 HPV 11). HPV+ status was identified slightly more often in women (NS) and in younger patients (P = 0.04); 2 female patients with aBSCC had a prior history of SCC including 1 anal SCC and 1 vaginal SCC. HPV+ aBSCC had fewer GA/tumor (P < 0.0001), more inactivating mutations in RB1 (P = 0.032), and fewer inactivating GA in CDKN2A (P < 0.0001), CDKN2B (P = 0.05), TERT promoter (P = 0.0004) and TP53 (P < 0.0001). GA in genes associated with urothelial carcinoma including FGFR2 and FGFR3 were similar in both HPV+ and HPV- aBSCC groups. MTAP loss (homozygous deletion) which has emerged as a biomarker for PRMT5 inhibitor-based clinical trials was not identified in any of the 11 HPV+ aBSCC cases, which was significantly lower than the 28% positive frequency of MTAP loss in the HPV- aBSCC group (P < 0.0001). MTOR and PIK3CA pathway GA were not significantly different in the 2 groups. Putative biomarkers associated with immunotherapy (IO) response, including MSI and TMB status, were also similar in the 2 groups. PD-L1 expression data was available for a subset of both HPV+ and HPV- cases and showed high frequencies of positive staining which was not different in the 2 groups. CONCLUSIONS: HPV+ aBSCC tends to occur more often in younger patients. As reported in other HPV-associated squamous cell carcinomas, HPV+ aBSCC demonstrates significantly reduced frequencies of inactivating mutations in cell cycle regulatory genes with similar GA in MTOR and PIK3CA pathways. The implication of HPV in the pathogenesis of bladder cancer remains unknown but warrants further exploration and clinical validation.

Genomic context of NTRK1/2/3 fusion-positive tumours from a large real-world population.

Neurotrophic tropomyosin receptor kinase (NTRK) gene fusions are rare oncogenic drivers in solid tumours. This study aimed to interrogate a large real-world database of comprehensive genomic profiling data to describe the genomic landscape and prevalence of NTRK gene fusions. NTRK fusion-positive tumours were identified from the FoundationCORE® database of >295,000 cancer patients. We investigated the prevalence and concomitant genomic landscape of NTRK fusions, predicted patient ancestry and compared the FoundationCORE cohort with entrectinib clinical trial cohorts (ALKA-372-001 [EudraCT 2012-000148-88]; STARTRK-1 [NCT02097810]; STARTRK-2 [NCT02568267]). Overall NTRK fusion-positive tumour prevalence was 0.30% among 45 cancers with 88 unique fusion partner pairs, of which 66% were previously unreported. Across all cases, prevalence was 0.28% and 1.34% in patients aged ≥18 and <18 years, respectively; prevalence was highest in patients <5 years (2.28%). The highest prevalence of NTRK fusions was observed in salivary gland tumours (2.62%). Presence of NTRK gene fusions did not correlate with other clinically actionable biomarkers; there was no co-occurrence with known oncogenic drivers in breast, or colorectal cancer (CRC). However, in CRC, NTRK fusion-positivity was associated with spontaneous microsatellite instability (MSI); in this MSI CRC subset, mutual exclusivity with BRAF mutations was observed. NTRK fusion-positive tumour types had similar frequencies in FoundationCORE and entrectinib clinical trials. NTRK gene fusion prevalence varied greatly by age, cancer type and histology. Interrogating large datasets drives better understanding of the characteristics of very rare molecular subgroups of cancer and allows identification of genomic patterns and previously unreported fusion partners not evident in smaller datasets.

Is alpha2-macroglobulin important in female stress urinary incontinence?

BACKGROUND: Loss of mechanical stability of the urethra and bladder is thought to be important in the development of stress urinary incontinence (SUI). The vaginal wall is the main supporting tissue for pelvic organs and changes in components of supporting tissues are known to be involved in the pathophysiology of SUI. METHODS: We evaluated changes in expression of alpha2-macroglobulin (alpha2-M), a protease inhibitor, in vaginal wall tissues from premenopausal women (aged 42-45 years) with SUI (n = 28) compared with menstrual cycle-matched continent women (controls, n = 29). The distribution of alpha2-M in vaginal wall tissues and fibroblasts was analysed by immunohistochemistry and immunofluorescence. Expression levels of alpha2-M mRNA and protein was determined by relative real-time quantitative PCR and enzyme-linked immunosorbent assay, respectively. Protease inhibition was measured to assess bioactivity. RESULTS: Vaginal wall tissues do express alpha2-M. Expression of alpha2-M mRNA and protein was significantly higher in tissues from controls compared to women with SUI in both proliferative and secretory phases (P < 0.05). Protease inhibitory activity of alpha2-M was significantly higher in tissues from controls compared to women with SUI in the secretory phase (P < 0.05), but we found no difference in the proliferative phase between groups. alpha2-M protein level was lower in the proliferative phase than the secretory phase in both controls and SUI patients, while for alpha2-M mRNA this was found only in controls. CONCLUSIONS: Decreased expression of alpha2-M mRNA and protein and protease inhibitory activity in the vaginal wall tissues of women with SUI may contribute to the development of SUI.

[Features of ontogenesis of uroliths].

The aim of the study was investigation of urolith growth process using the method of ontogenetic analysis. A total of 435 autochtonic uroliths obtained after surgery or spontaneous elimination from 422 patients with urolithiasis were studied with roentgenophasic analysis on diffractometer DRON-3, IR-spectroscopy, electron-probe. The concrements incorporate several zones with a nucleus as one of the zones. In some cases spherolith consisted of several splitted individuums with different orientation. Their nuclei contained phosphates and organic substance resultant from renal inflammation. In the other cases lithogenesis of the spherolith started from monocrystal microscopic nucleus which arrived from the kidney. The number of spherolith emergences can be interpreted as a rhythmic course of the disease. A prolonged macrorhythm characterizes stable disease. Formation of cut surfaces of the spherolith defines interruption of rhythmic zonality. A change in the composition of the crystal medium does not stop concrement growth, it provokes replacement of one mineral phase for the other. The ontogenetic analysis has detected that in the position of the concrement in the kidney mineral substance of its deep zones undergoes phasic transformations and morphological alterations. In changing medium conditions there are recovery of surfaces of solution with a change of a mineral phase, formation of new growth rhythms, aggregation and compression of the particles. This explains mixed composition of most of uroliths.

AMPK promotes tolerance to Ras pathway inhibition by activating autophagy.

Targeted inhibitors of oncogenic Ras (rat sarcoma viral oncogene)-Raf signaling have shown great promise in the clinic, but resistance remains a major challenge: 30% of tumors with pathway mutations do not respond to targeted inhibitors, and of the 70% that do respond, all eventually develop resistance. Before cancer cells acquire resistance, they respond to initial drug treatment either by undergoing apoptosis ('addiction') or by surviving treatment albeit with reduced growth ('tolerance'). As these drug-tolerant cells serve as a reservoir from which resistant cells eventually emerge, inhibiting the pathways that confer tolerance could potentially delay or even prevent recurrence. Here, we show that melanomas and other cancers acquire tolerance to Ras-Raf pathway inhibitors by activating autophagy, which is mediated by the cellular energy sensor AMP-activated protein kinase (AMPK). Blocking this AMPK-mediated autophagy sensitizes drug-tolerant melanomas to Ras-Raf pathway inhibitors. Conversely, activating AMPK signaling and autophagy enables melanomas that would otherwise be addicted to the Ras-Raf pathway to instead tolerate pathway inhibition. These findings identify a key mechanism of tolerance to Ras-Raf pathway inhibitors and suggest that blocking either AMPK or autophagy in combination with these targeted inhibitors could increase tumor regression and decrease the likelihood of eventual recurrence.

Duodenal stump tumor.

A rare case of duodenal stump tumor is described. The patient was an 84-year-old woman who had undergone a subtotal gastrectomy nine years previously. The polypoid tumor of the duodenal stump may have been a factor in the production of extrahepatic biliary obstruction, for which surgical treatment was required. The aged patient withstood the operation well.