New target genes in endometrial tumors show a role for the estrogen-receptor pathway in microsatellite-unstable cancers.

Microsatellite instability (MSI) in tumors results in an accumulation of mutations in (target) genes. Previous studies suggest that the profile of target genes differs according to tumor type. This paper describes the first genome-wide search for target genes for mismatch repair-deficient endometrial cancers. Genes expressed in normal endometrium containing coding repeats were analyzed for mutations in tumors. We identified 44 possible genes of which seven are highly mutated (>15%). Some candidates were also found mutated in colorectal and gastric tumors. The most frequently mutated gene, NRIP1 encoding nuclear receptor-interacting protein 1, was silenced in an endometrial tumor cell line and expression microarray experiments were performed. Silencing of NRIP1 was associated with differences in the expression of several genes in the estrogen-receptor network. Furthermore, an enrichment of genes related to cell cycle (regulation) and replication was observed. We present a new profile of target genes, some of them tissue specific, whereas others seem to play a more general role in MSI tumors. The high-mutation frequency combined with the expression data suggest, for the first time, an involvement of NRIP1 in endometrial cancer development.

Characterization of N-cadherin unbinding properties in non-malignant (HCV29) and malignant (T24) bladder cells.

The expression of N-cadherin, characteristic of various cancers, very often leads to changes in the cells' adhesive properties. Thus, we sought to find out if N-cadherin expressed in various, but cancer-related cells, differs in its functional properties that could contribute to variations in cells' phenotypes. In our work, measurements of an unbinding force of a single N-cadherin molecule, probed with the same antibody both on a surface of living non-malignant (HCV29) and malignant cells (T24) of bladder cancer, were carried out with the use of an atomic force microscopy. The results show the enhanced N-cadherin level in T24 malignant cells (8.7% vs. 3.6% obtained for non-malignant one), confirmed by the Western blot and the immunohistochemical staining. The effect was accompanied by changes in unbinding properties of an individual N-cadherin molecule. Lower unbinding force values (26.1 ± 7.1 pN) in non-malignant cells reveal less stable N-cadherin complexes, as compared to malignant cells (61.7 ± 14.6 pN). This suggests the cancer-related changes in a structure of the binding site of the antibody, located at the extracellular domain of N-cadherin.

Dose response and kinetics of foci disappearance following exposure to high- and low-LET ionizing radiation.

PURPOSE: The effect of different radiation qualities on (i) 53BP1 (p53 Binding Protein 1) and p-ATM (phosphorylated ataxia telangiectasia mutated) foci induction, and (ii) on the kinetics of foci disappearance was analysed. MATERIAL AND METHODS: Normal human skin fibroblasts were exposed to 240 kV broad-field X-rays or targeted with individually counted helium ((3)He) particles or protons ((1)H) from a Charged Particle Microbeam. Anti-p-ATM and anti-53BP1 antibodies were used for foci visualisation via immunocytochemistry. RESULTS: 1 Gy of X-rays yielded approximately 33 53BP1-positive foci/cell. The ratio between the number of delivered particles and yielded tracks was found to be 1:1 and 3:1 after targeted (3)He and (1)H irradiation, respectively. It was determined that approximately 50% of radiation-induced damage was repaired as measured by loss of foci during the first 2, 6, and 10 hours following X-ray, protons, and (3)He irradiation, respectively. CONCLUSIONS: There was significant radiation quality dependence for 53BP1- and p-ATM-positive foci induction observed. Foci disappearance was radiation dose-independent in the samples irradiated with X-rays. Our results confirm that kinetics of foci disappearance depends on radiation quality, even when individual ions are targeted to cells.

Renal papillary carcinoma classification into subtypes may be reproduced by nuclear morphometry.

OBJECTIVE: To analyze relationships between nuclear features of papillary renal cell carcinoma (PapRCC) subtypes. STUDY DESIGN: The material for the study consisted of 53 cases, of which 29 were type 1, 17 type 2 and 7 intermediate. At least 100 nuclei per case were segmented from images of 4',6-diamidino-2-phenylindole-stained slides. The geometric and texture features were extracted and used for analysis. RESULTS: In analysis of variance, it was shown that both individual cases and tumor types differ in the majority of the parameters. On nonsupervised expectation-maximization clustering, it was possible to classify the nuclei into separate categories, but PapRCC classes were not reproduced. The neural network classified the nuclei with sensitivity >0.6 and specificity >0.75. Analyzing the results for individual cases, the nuclei of type 1 cases were properly classified in 74-91%, nuclei of type 2 cases in 58-80% and nuclei of intermediate cases in 53-70%. CONCLUSION: Our findings show that PapRCC subtypes are distinct enough to be reproduced by image analysis.

[Cysts of the orbital bone and orbital sinus: clinical and morphological characteristics of the three cases]. / Torbiel odosobniona kosci oczodolu i zatoki czolowej: charakterystyka kliniczno-morfologiczna trzech przypadków.

BACKGROUND: Solitary bone cyst is rarely situated in facial bones. AIM: We discuss clinical view, results of radiological examinations and differential histopathological diagnostics of cases. RESULTS: We present 3 cases of patients: 51 year old man with cyst in frontal sinus; 29 year old man and 46 year old woman--both with changes in bones of the orbit. In all the cases results of histopathological examinations were similar. Cystic-shape pieces of vascularizated connective tissue were observed. Multiple cracks filled with cholesterol, macrophages with hemosiderin and occasionally multinuclear cells were noticed. CONCLUSIONS: Solitary bone cyst may be located in the periorbital bone, especially frontal. Excellent laryngological, optic and cosmetic results are results of the surgery. Suspicious of the solitary bone cyst is possible due to MR or CT imaging, but final diagnosis must be confirm by histological examination.

KRAS mutation profile in colorectal carcinoma and novel mutation--internal tandem duplication in KRAS.

Oncogenic KRAS mutations are associated with resistance to anti-EGFR therapy in colorectal carcinoma. Since anti-EGFR monoclonal antibodies are employed in clinical practice in advanced colorectal cancer, KRAS mutations have become an important predictor of therapy outcome. Mutational analysis of KRAS was performed on 163 adenocarcinoma samples. Exons 1-3 of KRAS were analyzed using SSCP and sequencing. Fifty seven (35%) carcinomas had missense point mutations in one of codons 12, 13, 59, 61, 117. In accordance with the published data, missense mutations in codons 12 (66%) and 13 (22%) were the most frequent. Mutations in codons 59 and 117 occurred with the same frequency as in codon 61. The only detected insertion occurred in exon 2. 15-bp insertion resulted in tandem duplication of codons 62-66. Presumably, 5 additional amino acids affected switch II conformation and sustained Ras activity due to decreased GTP hydrolysis. We report this unusual new type mutation.

Detection of isolated tumour cells in the blood and bone marrow of patients with gastric cancer by combined sorting, isolation and determination of MAGE-1, -2 mRNA expression.

The detection of isolated (circulating or disseminated) tumour cells (ITC) in patients with cancer requires very sensitive methods, as such cells are very rare. In the present study, the method that combines the negative isolation of CD45- leukocytes from the blood and bone marrow of patients with gastric cancer by flow cytometry, followed by the positive isolation of single cytokeratin-positive (CK+) cells by a Laser Capture Microdissection System for the determination of MAGE-1, -2 mRNA expression was used to detect ITC. This study shows that this method is highly sensitive as it allows to determine beta-actin-mRNA expression in a single CK+ cell. Using > or =5 CK+ cells as a cut-off level, the MAGE-1 mRNA expression was detected in 100% of CK+ cells in the peripheral blood and in 75% of bone marrow samples of patients with gastric cancer. The MAGE-2 mRNA expression was observed in 40 and 58% of samples, respectively. Furthermore, an analysis of primary tumours and locoreginal lymph nodes with respect to the mRNA expression of the two genes showed that MAGE-1 mRNA expression was detected in 88% of the primary tumours and in 67% of the lymph node samples, whereas the MAGE-2 mRNA expression was observed in 72 and 67% of the cases, respectively. Thus, the method described here allows the precise and sensitive determination of tumour-associated gene expression in single ITC present in the blood and bone marrow of patients with gastric cancer.

Clinicopathologic profile of gastrointestinal stromal tumors (GISTs) with primary KIT exon 13 or exon 17 mutations: a multicenter study on 54 cases.

Gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms driven by oncogenic, mutational activation of KIT or platelet-derived growth factor receptor alpha (PDGFRA). GIST-specific KIT or PDGFRA mutations have been linked to tumor location, tumor cell morphology and clinical behavior. The purpose of this study was to evaluate the clinicopathologic profile of GISTs that have KIT exon 13 or exon 17 mutations. Through the collaboration of several GIST research groups, we gathered 54 cases from the pre-imatinib era that had such primary mutations. From our observations and those in the literature, we estimate that the frequency of these mutations is no higher than 1-2%. Almost all (32 of 33, 97%) of the KIT exon 13 mutations were the 1945A>G substitution leading to Lys642Glu. A majority (15 of 21, 71.4%) of the KIT exon 17 mutations were the 2487T>A substitution leading to Asn822Lys. Demographic and clinicopathologic data were available for 26 and 14 KIT exon 13 and exon 17 mutant GISTs, respectively. Median age and male to female ratio were similar to ones reported in other GIST studies. Small intestinal tumors were two times more frequent than gastric ones among KIT exon 17 mutants. Also, intestinal tumors were slightly overrepresented among KIT exon 13 mutants when compared with population-based studies. The majority of KIT exon 13 or exon 17 mutants had a spindle-cell morphology and only a few had epithelioid features. Tumor size varied from 1.2 to 25 cm and average mitotic rates were 9.5 and 4.2 for KIT exon 13 and exon 17 mutants, respectively. Gastric KIT exon 13 mutant GISTs tend to be slightly larger and more aggressive than gastric GISTs in average, whereas the behavior of small intestinal GISTs with KIT exon 13 mutations does not differ from other small intestinal GISTs. The latter is also true for all KIT exon 17 mutant GISTs.

Incidence of lymphomas in Poland. The national register data for 2006.

In Poland, data on the incidence and mortality associated with malignancies are collected by the National Cancer Register (NCR). The Register is based on the International Classification of Diseases (ICD-10), which does not allow for assessing the incidence of lymphatic neoplasms classified according to the WHO classification system enforced since 2001. Under the National Program of Combating Neoplastic Diseases that focuses on detection and diagnosing malignant lymphomas in Poland in order to record and precisely classify lymphatic neoplasms, in 2006, the Haematopathological Section of the Polish Society of Pathologists, acting in collaboration with the Polish Lymphoma Study Group, initiated a nationwide register of lymphatic malignancies, a continuation of the Register of Lymphomas for the Province of Malopolska. The register not only renders epidemiological data more specific, but also allows for a comprehensive quality control.

Gastric solid glomus tumor and multiple glomangiomyomas of the large bowel with intravascular spread, multifocal perivascular proliferations and liver involvement.

The authors present a case of multiple glomus tumors (GTs) of the gastrointestinal tract, representing the type of a gastric glomus tumor proper and large bowel glomangiomyomas with myopericytoma-like features, observed in a 46-year old female, with multifocal perivascular proliferations of primitive cells and hepatic involvement. Histologically, the multilobular gastric tumor and hepatic lesions corresponded to a typical glomus tumor, while the tumor situated in the transverse colon, up to 7 cm in diameter, presented as a glomangiomyoma infiltrative (with myopericytoma-like foci), and satellite tumors in the large bowel mucosa, 0.5-0.7 cm in diameter, represented small glomangiomyomas. In addition, the patient demonstrated two types of concomitant vascular lesions: 1/ intravascular spread in the form of neoplastic plugs that obliterated the lumen of medium-size veins, and 2/ microscopic perivascular proliferation of primitive, small cells seen in the vicinity of the main tumor and in the adjacent adipose tissue. The patient has been ill for 2.5 years; she has been subjected to a partial colectomy with a resection of the small intestinal loop, greater omentum and the right ovary, followed by chemotherapy. At present, she is stable, and the infiltration--especially in the epigastric region--has decreased. The picture may confirm the theory that multiple GTs develop in association with multifocal proliferation of perivascular stem cells, as well as that their ability to penetrate into the lumen of large vessels gives origin to satellite tumors, which are not necessarily metastatic. It seems that at present, the group of perivascular SMA+ tumors may include infantile-type myofibromatosis in adults, myopericytoma, glomangio(myo)pericytoma, glomangiomyoma, glomus tumor proper, and glomangioma. Most likely, also some tumors previously classified as hemangiopericytomas belong to this group. The distinctive feature present in at least some of the above listed perivascular tumors is their synchronous or metachronous growth in a particular region and their ability to occupy intravascular space as nodules or solid bands, which in turn may give origin to satellite tumors. Multifocal lesions associated with a short survival in a given patient will obviously support the presence of metastatic disease. In the remaining cases, determination whether the patient has metastatic disease requires deep consideration and caution, also while deciding on treatment to be employed.

The gain-of-function JAK2 V617F mutation shifts the phenotype of essential thrombocythemia and chronic idiopathic myelofibrosis to more "erythremic" and less "thrombocythemic": a molecular, histologic, and clinical study.

We investigated the prevalence of the JAK2 V617F gain-of-function mutation in patients with Philadelphia chromosome-negative chronic myeloproliferative disorders (Ph- MPD) and explored the links between JAK2 mutational status and the clinicopathologic picture of essential thrombocythemia (ET), chronic idiopathic myelofibrosis (CIMF), and polycythemia vera (PV). Allele-specific polymerase chain reaction results for 59 ET, 18 CIMF, and 9 PV cases were compared with values for clinical variables at presentation and last follow-up and with the diagnostic trephine bone marrow biopsy pictures. JAK2 V617F was found in 38 (64%) of ET cases, 7 (39%) of CIMF cases, and 9 (100%) of PV cases. The ET patients with the mutant JAK2 showed significantly higher (although not overtly polycythemic) red blood cell parameter values, lower platelet counts, and higher white blood cell counts. Similar trends were found in CIMF. Megakaryocyte clustering was much less pronounced in the CIMF cases with mutant JAK2, with an analogous trend occurring in the ET cases. Bone marrow cellularity values and the numbers of CD34+ and CD117+ blasts in the ET and CIMF groups did not differ. Fibrosis was slightly less marked in the ET cases with mutant JAK2. The mutation did not significantly influence the clinical course during the follow-up in either disease in the short term (median follow-up, 22 months). The JAK2 V617F mutation is prevalent in all Ph- MPD and may skew their presenting phenotype, including bone marrow histology, toward a more "erythremic" and less "thrombocythemic" phenotype.

Predicting kidney function from renal biopsy. Semiquantitative versus quantitative approach.

The term glomerulonephritis encompass a heterogeneous group of diseases; these are a important cause of end stage renal disease. Although several evidence exist, that the main prognostic factors are extraglomerular lesions, no quantitative assessment is usually done. In nephropathological practice a semiquantitative approach is preferred. However, most of work on extraglomerular lesions significance was done with quantitative methods. The aim of the study was to compare the effects of quantitative and semiquantitative assessment of extraglomerular lesions in glomerulonephritis. The material consisted of 120 renal biopsies. On inspection, percentage of sclerosed glomeruli, degree of interstitial fibrosis, degree of interstitial infiltration, degree of tubular atrophy were and degree of mesangial matrix expansion assessed. For quantitative measurements AnalySIS 3.0 pro image analysis system was used. Relative interstitial volume, volume of interstitial infiltrate, with their variability--ross sectional areas of proximal and distal tubules were assessed by point counting method. Relative interstitial volume was significantly correlated to percentage of sclerosed glomeruli (R = 0.33 p < 0.001), degree of tubular atrophy (gamma = 0.57 p < 0.00001), degree interstitial fibrosis (gamma = 0.31 p < 0.0002) and mesangial matrix expansion (gamma = 0.24 p < 0.001). Semiquantitative and quantitative assessment of interstitial infiltrate was significantly correlated as well (gamma = 0.81 p < 0.001). Semiquantitatively assessed degree of tubular atrophy showed significant relation to total proximal tubular area (gamma = -0.30 p = 0,004). Percentage of sclerosed glomeruli was significantly correlated to creatinine level (R = 0.24 p = 0.03), but not to urea level (R = 0.09, NS). Semiquantitatively assessed degree of interstitial fibrosis showed only marginal correlation to creatinine level (gamma = 0.18 NS), however degree of interstitial infiltration was significantly correlated to creatinine (gamma = 0.34 p = 0.002) and urea level (gamma = 0.22 p = 0.06). Degree of tubular atrophy was significantly correlated to creatinine (gamma = 0.43 p < 0.001) and urea level (gamma = 0.28 p = 0.015). Relative interstitial volume was the very most important correlate of creatinine (R = 0.47 p < 0.0001) and urea level (R = 0.30 p < 0.01). In conclusion, it was confirmed, that the strongest correlate of renal function is relative interstitial volume. Some, but not all of semiquantitative parameters are also significantly correlated to kidney function.

Immunophenotype of isolated tumour cells in the blood, bone marrow and lymph nodes of patients with gastric cancer.

Immunophenotype of isolated (disseminated or circulating) tumour cells (ITC) in the blood, bone marrow and lymph nodes were studied in patients with gastric cancer. Coexpression of metalloproteinases inducer (EMMPRIN), chemokine receptors (CCR6, CXCR4) and adhesion molecules (Ep-CAM, CD44) was determined on cytokeratin positive (CK+) cells in CD45- cell population sorted out from the blood and/or bone marrow. Eight cytospin samples of blood and 69 samples of bone marrow containing CK+ cells from patients with gastric cancer were included into study. Expression of EMMPRIN and CCR6 were noted in a half of CK+ samples (of blood/bone marrow) whereas the expression of CXCR4 and Ep-CAM was much lower. Analysis of paired data of these determinants expression on CK+ cells showed no association between them. Expression of EMMPRIN, Ep-CAM, CCR6, CCR7, CXCR1, and CXCR4 on ITC in lymph nodes was determined by flow cytometry. In 18 lymph nodes (out of 36 assayed) CK+ cells were found. The expression of CCR6 and Ep-CAM on CK+ cells was observed in almost all studied lymph nodes, CXCR1--in half of them. The expression of EMMPRIN and CCR7 cells was lower. These results suggest that ITC of gastric cancer express variably several molecules that may be involved in metastasis formation.

Presence of homozygous KIT exon 11 mutations is strongly associated with malignant clinical behavior in gastrointestinal stromal tumors.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of gastrointestinal tract. GISTs range from benign indolent neoplasms to highly malignant sarcomas. Gain-of-function mutations of tyrosine kinase receptors, KIT or PDGFRA, have been identified in most GISTs. In this study, we report 36 GIST patients whose tumors had homozygous KIT exon 11 mutations detected by direct sequencing of PCR products. Loss of heterozygosity in KIT locus and other chromosome 4 loci were documented in majority of these tumors. However, fluorescence in situ hybridization with KIT locus-specific probe and chromosome 4 centromeric enumeration probe showed no evidence of KIT hemizygosity in a majority of analyzed cases. These findings are consistent with duplication of chromosome 4 with KIT mutant allele. Homozygous KIT exon 11 mutations were found in 33 primary tumors and 7 metastatic lesions. In two cases, shift from heterozygosity to homozygosity was documented during tumor progression being present in metastases, but not in primary tumors. Among primary GISTs, there were 16 gastric, 18 intestinal and 2 from unknown locations. An average primary tumor size was 12 cm and average mitotic activity 32/50 HPFs. Out of 32 tumors 29 (90.6%) with complete clinicopathologic data were diagnosed as sarcomas with more than 50% risk of metastatic disease, and 26 of 29 patients with follow-up had metastases or died of disease. An average survival time among pre-imatinib patients, who died of the disease was 33.4 months. Based on these findings, we conclude that presence of homozygous KIT exon 11 mutations is associated with malignant course of disease and should be considered an adverse prognostic marker in GISTs.

Evaluation of HER2/neu gene amplification in patients with invasive breast carcinoma. Comparison of in situ hybridization methods.

One of the prognostic and predictive factors in invasive breast carcinomas is determination of the HER2/neu proto-oncogene amplification or HER2 protein overexpression. HER2 amplification/overexpression is associated with a more aggressive disease course, greater likelihood of recurrence and generally poor prognosis. The authors compared the specificity, simplicity of a given procedure and method standardization, the simplicity of evaluation the results of each in situ hybridization method and time needed for performing the test. Sixty-three cases of infiltrating breast carcinoma from surgically excised tumors and core needle biopsies were included in the study. The first step was the determination of HER2 status by immunohistochemistry. The patients with moderate (2+) and strong (3+) overexpression of HER2 protein were chosen for determining HER2 amplification by three methods of in situ hybridization: FISH, CISH and in situ hybridization with silver autometallography. The statistical analysis revealed a good agreement between IHC and ISH methods and among ISH methods. The results indicate that all in situ hybridization methods are equivalent tools for evaluating HER2 gene amplification in archival material. There is no clear answer which method is the best assay to determine HER2 marker status, although the authors present some advantages and disadvantages of all the described techniques and a proposed algorithm for choosing a method for a given laboratory.

Immunophenotype and cytogenetics of mucinous tubular and spindle cell carcinoma of the kidney.

Mucinous tubular and spindle cell carcinoma (MTSCC) of the kidney is a rare, recently described entity. The authors present three new cases. The histological picture was that of classic MTSCC, with alternating small tubules located in a mucin-containing stroma, and spindle cell areas composed of bland, monomorphic cells. On immunohistochemistry, the tumors were positive for epithelial markers, including CK7 and CK18, vimentin, CD15, AMACR, and neuroendocrine markers, such as NSE and CD57. On FISH analysis we found losses on chromosomes 1 and 8, and gains of chromosomes 7 and 17. This is the first report of this rare entity in Polish medical literature.

[Own experience in treatment of patients with advanced tumours of the paranasal sinuses and the orbit, penetrating to the anterior and medial cranial fossa--preliminary report]. / Wlasne doswiadczenie w leczeniu rozleglych guzów zatok przynosowych i oczodolu zajmujacych struktury przedniego i/lub srodkowego dolu czaszki--doniesienie wstepne.

AIM: Craniofacial resection provides multidirectional approaches to remove nasal and paranasal tumours that involve the skull base. Vital structures, such as the dura, brain, and blood vessels, can be protected or resected and reconstructed safely. An en bloc excision of the tumour can be accomplished. The purpose of this study was to analyse oncological and functional results of craniofacial resection in our series of patients. MATERIAL AND METHODS: The medical records of 40 consecutive patients who had undergone craniofacial resection for tumours of the nasal cavity, paranasal sinuses, and adjacent areas were reviewed. The extent of disease, treatment results (the length of disease-free survival), complications, and prognoses were analysed. RESULTS: Lesions were malignant in 7 patients and benign in the remaining 33. All the patients had dural or intradural involvement. There was no operative death, and the rate of surgical morbidity was 20%. Craniofacial resection is the only surgical approach with acceptable rate of complications in selected patients with tumour comprising the anterior and medial cranial base, nasal cavity, paranasal sinuses, nasopharynx and orbits. Heroic resections are modern surgical procedures challenging both for ENT surgeons and neurosurgeons. The result is satisfactory when they are performed by a multi-specialist team.

Alterations of the retinoblastoma and p16 pathway correlate with promoter methylation in malignant fibrous histiocytomas.

Recent reports indicate that the alterations in the p16 and pRb pathways can influence tumour progression and poor prognosis in several tumours. The objective of this study was to analyse p16 and pRb expression in161 patients with malignant fibrous histiocytomas (MFH). By immunohistochemistry, p16 and pRb were demonstrated in 25% and 56% of MFH, respectively. Cox regression analysis demonstrated an independent prognostic influence of both genes. Generally, the loss of p16 and pRb expression correlated with poorer prognosis. Promoter methylation of p16 was found in 16/42 of p16 negative MFH and of pRb in 2/42 of pRb-negative MFH. It can be concluded that p16 and pRb alterations play an important role in the progression of soft tissue sarcomas.

Clonal lymphocytic populations in Philadelphia-negative chronic myeloproliferative disorders: is the T-cell clonality of 'undetermined' significance (TCUS) linked to a worse clinical outcome?

This study examined the clonality of B- and T-cells by PCR in 83 patients with Philadelphia-negative myeloproliferative disorders (Ph-MPD), to investigate its clinical and morphological correlates. Clonal lymphocytic populations were found in 23% of patients (T: n = 20, B: n = 3), with no frequency differences between ET, CIMF and PV. At the presentation, patients with clonal bands were older (58.1+/-13.8 vs 47.5+/-14.6, p = 0.0039), but did not differ in other clinical parameters. After the median follow-up of 21 months they were less likely to be asymptomatic (11.8% vs 41.1%, p = 0.029). The T-cell clonality was the strongest predictor of the symptomatic last follow-up by discriminant function analysis, surpassing the patient's age. This surprising negative prognostic impact of lymphocyte clonality in Ph-MPD may result from this phenomenon to be a better measure of the 'hematopoietic biologic age' than the metrical age itself.