Combined proliferating cell nuclear antigen and morphometric analysis in the diagnosis of cutaneous lymphoid infiltrates

Expression of proliferation markers and cell cycle regulators in T cell lymphoproliferative skin disorders

BACKGROUND

Abnormal cell proliferation, which results from deregulation of the cell cycle, is fundamental in tumorigenesis.

OBJECTIVES

To investigate the expression of proliferation markers and cell cycle regulators in a range of T cell lymphoproliferative skin diseases.

METHODS

We studied skin specimens of 51 patients with parapsoriasis (PP), mycosis fungiodes (MF), or lymphomatoid papulosis (LyP). Immunohistochemistry was performed for Ki-67, proliferating cell nuclear antigen (PCNA), minichromosome maintenance protein 7 (MCM7), and p21.

RESULTS

MF with stage IIB-IV and LyP showed a significantly greater number of Ki-67-positive cells than PP (P=0.02 and 0.001) and MF I-IIA (P=0.019 and 0.003), respectively. MCM7 staining revealed significantly higher labeling indices for MF IIB-IV and LyP when compared to PP (P=0.002 and 0.04) and MF I-IIA (P=0.0005 and 0.01), respectively. Compared to PP and MF I-IIA, MF IIB-IV was associated with significantly higher labeling indices for PCNA (P=0.006 and 0.0004). p21 staining was significantly increased in MF IIB-IV and LyP when compared to PP (P=0.006 and 0.003) and MF I-IIA (P=0.003). However, p21 staining was all in all very weak.

CONCLUSIONS

Ki-67 and PCNA seem to be useful immunohistological parameters for the correlation with the clinical stage of MF. In the differentiation and prognostication of T cell lymphoproliferative skin disorders, MCM7 may serve as a novel biomarker which is, in contrast to Ki-67 and PCNA, stable throughout the cell cycle.

Clinical and biological applications of image analysis in non-Hodgkin's lymphomas

The technical procedures and the main applications of image analysis in non-Hodgkin's lymphoma pathology have been described by reviewing the pertinent literature. With the advent of sophisticated computer-based technology, the possibility of objectively evaluating cell morphology, in situ marker expression, DNA indexes, and complex structural features may become a relevant part of the pathologist's expertise.

The status of immunohistochemical studies in lymphoma diagnosis

Immunohistochemical studies of formalin fixed paraffin embedded sections today constitute an essential component of the diagnostic process for malignant lymphoma. Lineage related markers are of value in distinguishing various lymphomas from anaplastic large and small cell carcinomas, and from sarcomas. Other more recently available markers are of value in establishing prognosis and, on occasion, in differentiating between neoplastic and reactive proliferations. Meticulous attention to reagent control and technical procedures is essential to all such studies.

Heterogeneity in cell proliferation and expression of p53 and bcl-2 during the indolent phase of germinal centre cell lymphoma: an explanation for clinical variability

Germinal centre cell lymphomas (GCCL) show a wide range of clinical outcomes from persistent indolent disease to large cell transformation. To investigate possible mechanisms of this heterogeneity, a combined morphometric and immunohistological study of p53, bcl-2 and cell proliferation was carried out. There was wide variation in p53 expression between biopsies and between individual follicles in the same tumour. A similar pattern of variation was seen using the cell-cycle marker MIB1, but this did not correlate with p53 expression. Even in cases in which a t(14;18) was demonstrated by PCR, variation occurred in the number of cells expressing bcl-2. On the basis of these results, we suggest that the probability of the clonal expansion of GCCL tumour cells carrying additional genetic abnormalities depends on a complex interaction of cell proliferation with p53 and bcl-2 expression, and that this may account for variation seen in the clinical behaviour seen in this group of tumours.

Proliferation cell nuclear antigen and soluble interleukin 2 receptor levels in cutaneous T cell lymphoma: correlation with advanced clinical diseases

Cutaneous T-cell lymphoma and leukemias (CTCL) are malignant clonal proliferation of T lymphocytes which have a predilection to home to and proliferate in skin. There are no clinical and laboratory parameters which consistently correlate with stage of disease, which varies from patch, plaque, tumor, or erythroderma. Soluble IL-2 receptor (sIL2-R) levels are elevated both in benign and malignant diseases involving immune activation. Proliferation cell nuclear antigen (PCNA) is a marker of the G1 and G/S phases of cell cycle and can be used to quantitate proliferation. We studied 43 skin biopsies of CTCL in various clinical stages for the presence of PCNA via immunoperoxidase techniques to establish a relationship between PCNA and the stage of disease. In addition, sIL2-R levels were determined in 14 patients. PCNA reactivity was detected in the nuclei of infiltrating cells in a total of 25 patients (58%). According to clinical stage there were 2/12 patch (12%), 9/17 plaque (53%), 4/4 tumor (100%) and 9/10 erythrodermic (90%) stage patients with PCNA positive cells. Thus PCNA positivity correlated with advanced clinical stage. sIL2-R levels were elevated in 14 of 14 patients and the degree of elevation correlated with advanced clinical stage of disease and with increased numbers of PCNA positive cells. Immunohistochemical studies for PCNA and serum sIL2-R levels can be used as laboratory parameters to correlate with clinical stage of disease and enhance prognostication in CTCL.