p53 protein expression in patients with myelodysplasia treated with allogeneic bone marrow transplantation

Tumor protein 53 mutations adversely affect the prognosis of myelodysplastic syndromes (MDS); however, few studies have reported on the prognostic significance of the expression of p53 protein in MDS. The current study investigated p53 immunoreactivity (p53-IR) in bone marrow biopsies (BMBs) obtained at diagnosis from 18 patients (6 females and 12 males; mean age, 50.5 years) with MDS that underwent bone marrow transplantation (BMT) to determine the associations between clinical and histopathological data and outcome. There were 5 refractory cytopenia with multilineage dysplasia (RCMD) and 13 refractory anemia with excess blasts, type 2 (RAEB-2) cases. p53-IR was assessed as the percentage of hematopoietic cells exhibiting intense nuclear staining. The cut off for positivity was 5% of stained cells. A positive p53-IR was detected in 7 patients (38.9%) and was associated with age (P=0.005) and pattern of BM fibrosis (P=0.03). A positive p53-IR was more frequent in females, in highly cellular BMBs and in RAEB-2 cases. Overall survival (OS) was associated with patients' age (P=0.01), hemoglobin level (P=0.04), type of MDS (P=0.05), degree of BM fibrosis (P=0.006) and number of BM blasts (P=0.05). The OS of patients with negative p53-IR tended to be longer compared with that of patients with positive p53-IR, although this difference was not statistically significant (P=0.1). Despite the limitation of the low number of cases, the present results indicate that a positive p53-IR at diagnosis is associated with clinically more aggressive MDS subtypes and adverse histological prognostic factors, such as BM fibrosis. Therefore, the evaluation of p53 expression of BMBs of patients with MDS may be introduced in the histopathological work-up of the disease.

Tubulocystic renal cell carcinoma disguised as a renal cyst

Even though CT scans are considered the gold standard to characterize a renal mass, sometimes they can be misleading, showing a solid renal mass as a cystic one. Tubulocystic renal cell carcinoma (TcRCC) is a rare and recently discovered RCC variant which radiologically may look like a Bosniak type II to IV, even if it has solid features. We describe a case of a patient with left kidney TcRCC initially diagnosed as a renal cyst, who finally underwent radical nephrectomy showing a large, solid neoplasm. Due to its unusual CT appearance, TcRCC can be confused with cystic lesions and several other benign or malignant entities. Ultrasound can be a useful aid for the characterization of these renal tumors.

Chronic kidney disease, severe arterial and arteriolar sclerosis and kidney neoplasia: on the spectrum of kidney involvement in MELAS syndrome

BACKGROUND

MELAS syndrome (MIM ID#540000), an acronym for Mitochondrial Encephalopathy, Lactic Acidosis and Stroke-like episodes, is a genetically heterogeneous mitochondrial disorder with protean manifestations and occasional kidney involvement. Interest in the latter is rising due to the identification of cases with predominant kidney involvement and to the hypothesis of a link between mitochondrial DNA and kidney neoplasia.

CASE PRESENTATION

We report the case of a 41-year-old male with full blown MELAS syndrome, with lactic acidosis and neurological impairment, affected by the "classic" 3243A > G mutation of mitochondrial DNA, with kidney cancer. After unilateral nephrectomy, he rapidly developed severe kidney functional impairment, with nephrotic proteinuria. Analysis of the kidney tissue at a distance from the two tumor lesions, sampled at the time of nephrectomy was performed in the context of normal blood pressure, recent onset of diabetes and before the appearance of proteinuria. The morphological examination revealed a widespread interstitial fibrosis with dense inflammatory infiltrate and tubular atrophy, mostly with thyroidization pattern. Vascular lesions were prominent: large vessels displayed marked intimal fibrosis and arterioles had hyaline deposits typical of hyaline arteriolosclerosis. These severe vascular lesions explained the different glomerular alterations including ischemic and obsolescent glomeruli, as is commonly observed in the so-called "benign" arteriolonephrosclerosis. Some rare glomeruli showed focal segmental glomerulosclerosis; as the patient subsequently developed nephrotic syndrome, these lesions suggest that silent ischemic changes may result in the development of focal segmental glomerulosclerosis secondary to nephron loss.

CONCLUSIONS

Nephron loss may trigger glomerular sclerosis, at least in some cases of MELAS-related nephropathy. Thus the incidence of kidney disease in the "survivors" of MELAS syndrome may increase as the support therapy of these patients improves.

Intrasinusoidal bone marrow infiltration and splenic marginal zone lymphoma: a quantitative study

Intrasinusoidal infiltration (ISI) is a pattern of invasion that is rarely found on bone marrow (BM) biopsies, and is considered as a hallmark of splenic marginal zone cell lymphoma (SMZL). We analysed BM biopsies showing intrasinusoidal infiltration from 54 consecutive patients with different types of lymphoma to verify if ISI quantity was a diagnostic criterion for SMZL. There were 35 primary splenic lymphoma (PSL) and 19 non-PSL; 28 SMZL, three non-splenic MZL, six mantle cell, six small lymphocytic, four follicular, four diffuse large B cell, one peripheral T cell, one lymphoplasmacytic and one anaplastic large-cell lymphoma. The quantity of BM infiltrate was assessed on CD45, CD20 and CD3 stained sections. The mean percentage of total (TI) and intrasinusoidal (ISI) lymphocytes was calculated in 10 areas for each case. TI quantity was 21.57 in PSL and 35.05 in non-PSL (P = 0.04). ISI quantity was 5.23 in PSL and 7.62 in non-PSL (P = 0.08), 5.83 in SMZL and 2.83 in other types of PSL (P = 0.12), 4.46 in non-splenic MZL and 8.21 in other types of non-PSL (P = 0.28). No difference in ISI quantity was found among the lymphoma subtypes, either in PSL (P = 0.74) or non-PSL (P = 0.3). The data demonstrate that ISI quantity in BM biopsies is not a reliable diagnostic parameter for SMZL.

Human herpesvirus type 7 in Hodgkin's disease

Several lines of evidence have pointed to the involvement of a viral agent in the pathogenesis of Hodgkin's disease (HD). Therefore we investigated the presence of human herpesvirus type 7 (HHV-7) in 53 cases of HD by polymerase chain reaction (PCR), DNA in situ hybridization (ISH) and immunohistochemistry. HHV-7 DNA was frequently detected (68% of the cases) in HD biopsies by PCR independently of the histological type, whereas only 32% (P<0.05) of positive cases were found in 19 reactive lymph nodes. However, by applying the quantitative PCR technique, the majority of the samples showed a low level of viral load. Moreover, ISH for HHV-7 DNA was positive in a low number of small T lymphocytes and consistently negative in Hodgkin and Reed-Sternberg (HRS) cells, which appeared negative for HHV-7 also at immunohistochemistry. These results indicate that the high frequency of HHV-7 infection in HD: (i) is probably non-productive, (ii) mainly involves small lymphocytes belonging to the T-lineage, and (iii) is probably due to the recruitment of non-malignant reactive cells in HD tissue.