Detection of low-level tumor cells in allergic contact dermatitis induced by mechlorethamine in patients with mycosis fungoides

Adverse cutaneous reactions to chemotherapeutic drugs

Drug reactions resulting from chemotherapy agents are common and frequently affect the skin. Although often benign, a select few of these cutaneous reactions may necessitate immediate changes to the antineoplastic regimens. Given the diversity of chemotherapeutic skin reactions and their complex implications on patient management, an organized conceptual schema is imperative for proper patient care. We evaluate a number of commonly seen chemotherapy-induced skin toxicities organized by pathogenic mechanism and drug class, providing a framework for the identification and categorization of adverse events to prevent unrecognition. Groupings of these reactions include direct cytotoxicity and/or drug accumulation, immunologic hypersensitivity, and aberrant molecular signaling.

Specific infiltrate of Hodgkin lymphoma at site of cellulitis mimicking secondary cutaneous involvement

Hodgkin lymphoma (HL) usually involves the lymph nodes, but concomitant cutaneous manifestations can also occur. The diagnosis of cutaneous involvement by HL must be supported by specific clinical and histopathological findings. We describe the case of a 56-year-old man recently diagnosed with HL of the left axillary nodes who developed cellulitis of the left trunk. Histopathological examination of a skin biopsy specimen revealed the presence of large atypical lymphoid cells with the same immunophenotype of those located in the lymph node affected by HL. Our case adds to the many cutaneous infiltrations by neoplastic cells during the course of an inflammatory skin disease, namely cellulitis.

The significance of multiplex PCR/heteroduplex analysis-based TCR-γ gene rearrangement combined with laser-capture microdissection in the diagnosis of early mycosis fungoides

BACKGROUND

The diagnosis of early mycosis fungoides (MF) is a big challenge to dermatologists and dermatopathologists because it lacks specific clinicopathologic features.

METHODS

Fifty-two paraffin-embedded skin samples from 50 patients, including 31 with suspected MF, 10 with typical MF and 9 with benign inflammatory dermatosis (BID), were obtained from our archives. DNA was extracted both by traditional phenol-chloroform method and by the laser-capture microdissection (LCM)-proteinase K approach. The T(VG) /T(JG) , V(2-5) /V(8-12) /JGT(1) and BIOMED-2-TCR-γ primers were used to assess TCR-γ monoclonal rearrangement as measured by polymerase chain reaction (PCR).

RESULTS

In the suspected MF group, clonal TCR-γ gene rearrangements were detected in 11/31 cases (35.5%) by phenol-chloroform DNA extraction and in 25/31 cases (80.7%) by LCM-proteinase K extraction (p < 0.05). While T-cell clonality was detected in 8/10 cases (80%) by the phenol-chloroform method and 10/10 cases (100%) by LCM (p > 0.05) in the typical MF group, no TCR-γ monoclonal rearrangement was detected in the BID group.

CONCLUSIONS

The strategy of multiple PCR/heteroduplex analysis for TCR-γ gene rearrangement combined with LCM increases the detection rate of clonal TCR-γ gene rearrangement in early MF cases and could provide strong evidence to confirm the diagnosis of early MF.

Low FAS/CD95 expression by CTCL correlates with reduced sensitivity to apoptosis that can be restored by FAS upregulation

FAS expression was generally low in 30 of 31 cutaneous T-cell lymphoma (CTCL) cases (mycosis fungoides/Sezary syndrome, SS) as well as in 5 of 6 large plaque parapsoriasis cases (a CTCL precursor). To investigate this phenomenon, we explored FAS transcript levels, cell-surface FAS protein expression and susceptibility to FAS-mediated apoptosis in four CTCL lines (MyLa, HH, SZ4, and SeAx), freshly isolated leukemic cells from a patient with SS, an acute lymphoblastic leukemia T-cell line (Jurkat), and JFL (a FAS-low variant of Jurkat). Results confirmed low FAS expression by the leukemic SS cells, HH, SZ4, SeAx, and JFL relative to normal peripheral blood mononuclear leukocytes and the other cell lines. There was a direct correlation among FAS transcript level, FAS protein level, and FAS-mediated apoptotic sensitivity in the CTCL samples. When the FAS-deficient cell lines were transfected with a wild-type FAS construct, FAS expression and sensitivity to FAS-mediated apoptosis were restored. In aggregate, these findings provide evidence that like normal T cells, CTCL cells exhibit a mechanistic connection between transcriptional regulation of FAS and sensitivity to FAS-mediated apoptosis, point to the development of FAS deficiency as one molecular mechanism responsible for acquired resistance to apoptosis in CTCL, and indicate that upregulation of FAS expression can restore sensitivity to apoptosis.

Diagnosis, staging, and monitoring of cutaneous T-cell lymphoma

Cutaneous T-cell lymphoma includes mycosis fungoides and its leukemic variant, the Sézary syndrome. This review discusses the clinical, histopathologic, immunophenotypic and immunogenotypic features of cutaneous T-cell lymphoma as they apply to the diagnosis, staging and monitoring of this disease.

Clonal T-cell receptor gamma-chain gene rearrangement by PCR-based GeneScan analysis in advanced cutaneous T-cell lymphoma: a critical evaluation

Detection of clonal T-cell receptor gamma (TCRgamma)-chain gene rearrangement is a promising approach to distinguish between cutaneous T-cell lymphomas (CTCLs) and reactive T-cell infiltrates. Despite the improved sensitivity by using the polymerase chain reaction (PCR) rather than Southern blot analysis, monoclonality could be demonstrated in only 53-90 per cent of CTCL biopsies in recent studies. In the present study, formalin-fixed, paraffin-embedded specimens of 21 selected patients with clear-cut advanced-stage CTCL were analysed using a semi-nested TCRgamma PCR with newly developed consensus primer pairs. Detection of PCR products was done by GeneScan analysis (GSA); this technique is advantageous due to its sensitivity and accuracy in the detection and size determination of PCR products and it is easier to interpret than direct read-outs from TGGE or DGGE gels. In serial dilution experiments, TCRgamma-PCR-GSA allowed the detection of clonal, rearranged T-cells with a high in vitro sensitivity against a polyclonal background (1-6 per cent). Despite the selection of clear-cut, advanced-stage CTCL cases, however, dominant clonal TCRgamma-chain gene rearrangement was found in only 16 of the 21 patients analysed, indicating an overall clinical sensitivity of 76 per cent. Specificity was evaluated using biopsy specimens from 21 control patients suffering from long-standing psoriasis (n=13) and eczema (n=8). Surprisingly, GeneScan profiles showing apparently single dominant peaks were detected in 14 per cent of these skin lesions, but these profiles turned out to be pseudo-monoclonal by repeated determinations. In conclusion, TCRgamma-PCR-GSA does not suffice reliably to exclude malignancy, due to its limited clinical sensitivity, but with precautions taken to detect pseudo-monoclonality and to secure specificity, TCRgamma-PCR-GSA is a valuable instrument in the diagnosis of CTCL.

Cutaneous infiltrate of chronic lymphocytic leukemia and relationship to primary cutaneous epithelial neoplasms

Chronic lymphocytic leukemia involves the skin in a small percentage of patients and may portend an ominous prognosis in some patients. We report a series of eight biopsies from seven different patients in which the cutaneous leukemic infiltrate was confined exclusively to the region immediately surrounding primary epithelial neoplasms including squamous cell carcinoma (6), basal cell carcinoma (1) and actinic keratosis (1). The malignant lymphocytes appear to constitute a host response to these neoplasms and do not appear to suggest a rapid downhill course for these patients. These observations serve to 1) suggest a new pattern of cutaneous involvement by leukemic cells and 2) offer some insights into potential cellular trafficking patterns of these neoplastic cells.

Transformed and nontransformed human T lymphocytes migrate to skin in a chimeric human skin/SCID mouse model

To study human T cell migration to human skin in vivo, we grafted severe combined immunodeficient mice with 500-microm thick human skin. Two weeks after grafting, epidermal and dermal structures in the grafts were of human origin. When we intraperitoneally injected grafted mice with clones of the human HUT-78 T cell line derived from a patient with cutaneous T cell lymphoma and Sézary syndrome, we detected in the grafts the rare Vbeta23-Jbeta1.2 T cell receptor transcripts characteristic for the HUT-78 clones. These signals were found 2-6 d after cell injection in about 40% of the grafted and HUT-78 cell injected mice but not in grafts from mice that received no exogenous T cells. In contrast to HUT-78 cells, which only accumulate in low number, grafts topically challenged with nickel sufate in vaseline from mice that were injected with autologous nickel-reactive T cell lines led to massive accumulation of T cells within 3 d. Only scattered T cells accumulated in the skin when grafted mice received vaseline plus T cells, nickel sulfate alone, T cells alone, or nickel sulfate plus an allogeneic nickel-nonreactive T cell clone. When the T cell lines were labeled with the fluorochrome PKH-26 before cell injection, spots of fluorescent label in the size and shape of cells were found in the grafts challenged with nickel. Together, these results clearly demonstrate that human T cells can migrate to human skin in this chimeric human/mouse model.

Leukemic cells within skin lesions of psoriasis in a patient with acute myelogenous leukemia

We report on an 81-year-old man with acute myelo-monocytic leukemia (FAB M4) and a long-standing history of psoriasis. Biopsy of psoriatic plaques revealed the coexistence of characteristic histopathologic aspects of psoriasis together with an infiltrate of blasts with features of myelo-monocytes, suggestive of a specific leukemic infiltrate within plaques of psoriasis. Immunohistologic stainings showed positivity of blasts for LN2 (CD74), MT1 (CD43), and lysozyme, consistent with a myeloid lineage of these cells. To the best of our knowledge, this is the first report on the association of psoriasis with myelogenous leukemia. The presence of leukemic cells within psoriatic skin plaques may be explained by non-specific recruitment of recirculating malignant cells to the skin. Alternatively, as psoriasis is an inflammatory disease involving granulocytes among other cell types, it may be hypothesized that leukemic cells retain to some extent their capability to respond to physiologic stimuli and enter the skin in response to specific chemotactic factors.