Phenotypic Switch of Endovascular Trophoblasts in Decidual Vasculopathy with Implication for Preeclampsia and Other Pregnancy Complications

BackgroundThis study aims to investigate decidual vasculopathy in preeclampsia at term and its relationship to spiral artery remodeling at implantation sites. Study design: Implantations sites with endovascular trophoblasts were reviewed from abortions with immunostaining for CD56. Placentas from patients with preeclampsia were also reviewed in association with other pathological features using placentas with decidual vasculopathy but not preeclampsia as controls. Results: Endovascular trophoblasts were phenotypically switched to express CD56 upon entering the spiral artery at implantation. CD56 expression is identified in classic decidual vasculopathy at term with or without preeclampsia. CD56 expression in addition to cytokeratin in decidual vasculopathy demonstrated the fetal trophoblastic origin, establishing the presence of endovascular trophoblasts at implantation and the decidual vasculopathy at term. Conclusion: Decidual vasculopathy at term contains the same CD56 positive extravillous endovascular trophoblasts seen with spiral artery remodeling in early pregnancy. CD56 may serve as a possible marker for decidual vasculopathy in the later stages of pregnancy.

The clinicopathological relevance of uniform CD56 expression in anaplastic large cell lymphoma: a retrospective analysis of 18 cases

Background

Anaplastic large cell lymphoma (ALCL) with uniform CD56 expression is a rare condition, that has been described in limited literature, and its clinicopathological features have not yet been well illustrated. The aim of our study was to fully investigate the clinical, histological, immunohistochemical and molecular features of CD56+ ALCL.

Methods

The clinical and histological characteristics of CD56+ ALCL cases were retrospectively evaluated. The immunohistochemical phenotype, status of Epstein-Barr virus (EBV) and T-cell receptor (TCR) gene rearrangement were examined. Overall survival was also analyzed.

Results

Eighteen (5.8%) cases with diffuse CD56 expression were identified out of 313 archived ALCL cases with CD56 test. CD56 expression was significantly higher in ALK+ systemic ALCLs (sALCLs) (13/64, 20.3%) than in ALK- sALCLs (3/101, 3.0%) (p < 0.001) as well as primary cutaneous ALCLs (2/148, 1.4%) (p < 0.001). Regarding the CD56+ ALK+ sALCLs, the median age was 20 years (range, 8–60 years) with a male-to-female ratio of 2.3:1, and these cases more frequently affected extranodal sites (11/38, 28.9%) rather than lymph nodes (2/26, 7.7%) (p = 0.038). Eleven (84.6%) cases presented with stage I-II diseases, which was significantly more than their CD56- ALK+ counterparts (45.5%) (p = 0.015). Histologically, 2 ALK+ cases were of small cell variant and all the others displayed characteristic morphology of classic ALCL. Regarding the immunophenotype, both CD30 and CD56 were diffusely positive in all cases. CD3, CD43, anaplastic lymphoma kinase-1 (ALK1), TIA-1, EMA expression was observed in 30.8% (4/13), 90.9% (10/11), 100% (13/13), 100% (9/9), and 80.0% (8/10) cases, respectively. EBV infection was consistently absent. Monoclonal TCR gene rearrangement was found in 100% (5/5) of investigated ALK+ cases. Chemotherapy with a CHOP regimen was most frequently employed. The 3-year overall survival (OS) rate for CD56+ ALK+ patients was 92.0%, compared with 73.0% for their CD56- counterparts, but there was no significant difference in OS between the two groups (p = 0.264).

Conclusions

Uniform CD56 expression is an unexpected condition in ALCL. Of ALK+ ALCLs, CD56 expression correlated with a high frequency of early stage and an extranodal predominance. It is of great importance to raise awareness of this condition and familiarity with its characteristic features to avoid diagnostic and therapeutic pitfalls. Further investigations are warranted for a better understanding of this unusual phenotype and the significance of CD56 expression in ALCL.

Prognostic factors of patients with newly diagnosed acute promyelocytic leukemia treated with arsenic trioxide-based frontline therapy

Prognostic factors for patients with acute promyelocytic leukemia (APL) treated in the context of arsenic trioxide (ATO)-based frontline regimes have not been established clearly. We retrospectively analyzed the clinical features, immunophenotypes, Fms-like tyrosine kinase-3 internal tandem duplication (FLT3-ITD), and outcomes of 184 consecutive newly diagnosed APL patients treated by intravenous ATO-based therapy. The median age was 40 years (14-77 years). The early death rate was 4.9% (9/184 patients). With a median follow-up time of 36 months (9-74 months), the 3-year relapse-free survival (RFS) and overall survival (OS) were 93.3% and 92.2%, respectively. Interestingly, there was no meaningful association between 3-year RFS and initial white blood cell count, FLT3-ITD status, or type of PML-RARA isoforms. In multivariable analysis, the CD56 expression was the only independent risk factor in terms of RFS (hazard ratio, 4.70; P=0.005). These results suggested that ATO-based therapy may ameliorate the unfavorable influence of previously known high-risk features; moreover, CD56 expression remains to be a potentially unfavorable prognostic factor in APL patients.

Naso-Sinusal T ALL With Aberrant Expression of CD56 Mimicking NK/T Non Hodgkin Lymphoma

T-acute lymphoblastic leukemia (T-ALL) represents 25 % of cases of acute lymphoblastic leukemia (ALL) in adults. The clinical presentation is dominated by a elevated number of white blood cells and in immunophenotype the lymphoblasts are generally Tdt positive and variably express CD1a, CD2, CD3, CD4, CD5, CD7, and CD8. NK/T non Hodgkin lymphoma is presented as a single lesion often ulcerated with torpid evolution affecting the nasal cavity, nasopharynx and/or palate. CD56 expression is while characteristic of NK-cells, and is also expressed on a subset of normal T cells. Its expression in ALL does not exclude the diagnosis and seems to be a prognostic factor of this disease. We report the case of a young woman with nasal cavity tumor which was initially diagnosed as T-cell lymphoma. This diagnosis was finally revised to conclude to T-ALL with CD56 aberrant expression.

Expression of CD56 is an unfavorable prognostic factor for acute promyelocytic leukemia with higher initial white blood cell counts

Expression of CD56 has recently been introduced as one of the adverse prognostic factors in acute promyelocytic leukemia (APL). However, the clinical significance of CD56 antigen in APL has not been well elucidated. We assessed the clinical significance of CD56 antigen in 239 APL patients prospectively treated with all-trans retinoic acid and chemotherapy according to the Japan Adult Leukemia Study Group APL97 protocol. All patients were prospectively treated by the Japan Adult Leukemia Study Group APL97 protocol. The median follow-up period was 8.5 years. Positive CD56 expression was found in 23 APL patients (9.6%). Expression of CD56 was significantly associated with lower platelet count (P = 0.04), severe disseminated intravascular coagulation (P = 0.04), and coexpression of CD2 (P = 0.03), CD7 (P = 0.04), CD34 (P < 0.01) and/or human leukocyte antigen-DR (P < 0.01). Complete remission rate and overall survival were not different between the two groups. However, cumulative incidence of relapse and event-free survival (EFS) showed an inferior trend in CD56(+) APL (P = 0.08 and P = 0.08, respectively). Among patients with initial white blood cell counts of 3.0 × 10(9)/L or more, EFS and cumulative incidence of relapse in CD56(+) APL were significantly worse (30.8% vs 63.6%, P = 0.008, and 53.8% vs 28.9%, P = 0.03, respectively), and in multivariate analysis, CD56 expression was an unfavorable prognostic factor for EFS (P = 0.04). In conclusion, for APL with higher initial white blood cell counts, CD56 expression should be regarded as an unfavorable prognostic factor.