Overexpression of Arginase 1 is linked to DNMT3A and TET2 mutations in lower-grade myelodysplastic syndromes and chronic myelomonocytic leukemia.

Immune dysregulation is a common feature of myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML), particularly in early stages. However, the genetic basis remains poorly understood. We recently reported that macrophages from mice deficient in tet methylcytosine dioxygenase 2 (Tet2), a model of MDS/CMML, are hyperinflammatory and have increased expression of arginase 1 (Arg1). In macrophages and myeloid derived suppressor cells (MDSCs) expression of Arg1 contributes to T-cell suppression and immune evasion by L-arginine depletion, in the setting of chronic inflammation and cancer. Since human MDS and CMML are driven by TET2 mutations and associated with chronic inflammation, we hypothesized that arginase enzymatic activity and ARG1 expression would be increased in human MDS/CMML bone marrow. Elevated arginase activity was observed in bone marrow mononuclear cells of MDS and CMML patients with lower-grade features. Immunohistochemical studies confirmed that myelomonocytic cells overexpress ARG1. Additionally, mutations in the epigenetic regulators TET2 and DNMT3A corresponded to high ARG1 expression and activity. These findings suggest ARG1 is a biomarker of immune dysregulation in early MDS and CMML. Recent murine findings have implicated Tet2 and Dnmt3a in regulation of innate immunity. Our study suggests similar changes may be driven by human TET2 and DNMT3A mutations.

Prolonged clinical remissions in patients with relapsed or refractory follicular lymphoma treated with autologous stem cell transplantation incorporating rituximab.

Three sequential phase II trials were conducted with different immunotherapy approaches to enhance the outcome of autologous transplant (high-dose therapy and autologous stem cell transplantation (HDT/ASCT)) for recurrent follicular lymphoma. Seventy-three patients were enrolled from 1996 to 2009. Patients received HDT/ASCT combined with (1) interferon-α 3 MU/m(2) subcutaneously (SC) three times per week (TIW) for 2 years post-ASCT, (2) rituximab (R) 375 mg/m(2) for in vivo purging 3-5 days pre-stem cell collection and 2 × 4 weekly R at 2 and 6 months post-ASCT, respectively, or (3) three infusions of R pre-stem cell collection followed by 6× R weekly and interferon-α 3 MU/m(2) SC TIW. Although not statistically significant, progression-free survival (PFS) for patients who received rituximab was 56.4 and 49.1% at 5 and 10 years compared to 36 and 21% in those who did not receive rituximab. Molecular relapse post-HDT/ASCT was the strongest predictor of PFS in a multivariate analysis. Molecular relapse was coincident with or preceded clinical relapses in 84% of patients who relapsed­median of 12 months (range 0-129 months). Adverse events included secondary malignancy, transformation to diffuse large B cell lymphoma, prolonged mostly asymptomatic hypogammaglobulinemia, and pulmonary fibrosis. The long-term toxicity profile must be considered when selecting patients for this treatment.

Assessment of endometrial sampling as a predictor of final surgical pathology in endometrial cancer.

BACKGROUND: The histology and grade of endometrial cancer are important predictors of disease outcome and of the likelihood of nodal involvement. In most centres, however, surgical staging decisions are based on a preoperative biopsy. The objective of this study was to assess the concordance between the preoperative histology and that of the hysterectomy specimen in endometrial cancer. METHODS: Patients treated for endometrial cancer during a 10-year period at a tertiary cancer centre were identified from a prospectively collected pathological database. All pathology reports were reviewed to confirm centralised reporting of the original sampling or biopsy specimens; patients whose biopsies were not reviewed by a dedicated gynaecological pathologist at the treating centre were excluded. Surgical pathology data including histology, grade, depth of myometrial invasion, cervical stromal involvement and lymphovascular space invasion (LVSI) as well as preoperative histology and grade were collected. Preoperative and final tumour cell type and grade were compared and the distribution of other high-risk features was analysed. RESULTS: A total of 1329 consecutive patients were identified; 653 patients had a centrally reviewed epithelial endometrial cancer on their original biopsy, and are included in this study. Of 255 patients whose biopsies were read as grade 1 (G1) adenocarcinoma, 45 (18%) were upgraded to grade 2 (G2) on final pathology, 6 (2%) were upgraded to grade 3 (G3) and 5 (2%) were read as a non-endometrioid high-grade histology. Overall, of 255 tumours classified as G1 endometrioid cancers on biopsy, 74 (29%) were either found to be low-grade (G1-2) tumours with deep myometrial invasion, or were reclassified as high-grade cancers (G3 or non-endometrioid histologies) on final surgical pathology. Despite these shifts, we calculate that omitting surgical staging in preoperatively diagnosed G1 endometrioid cancers without deep myometrial invasion would result in missing nodal involvement in only 1% of cases. CONCLUSIONS: Preoperative endometrial sampling is only a modest predictor of surgical pathology features in endometrial cancer and may underestimate the risk of disease spread and recurrence. In spite of frequent shifts in postoperative vs preoperative histological assessment, the predicted rate of missed nodal metastases with a selective staging policy remains low.

Interobserver agreement for endometrial cancer characteristics evaluated on biopsy material.

A shift toward a disease-based therapy designed according to patterns of failure and likelihood of nodal involvement predicted by pathologic determinants has recently led to considering a selective approach to lymphadenectomy for endometrial cancer. Therefore, it became critical to examine reproducibility of diagnosing the key determinants of risk, on preoperative endometrial tissue samples as well as the concordance between preoperative and postresection specimens. Six gynaecologic pathologists assessed 105 consecutive endometrial biopsies originally reported as positive for endometrial cancer for cell type (endometrioid versus nonendometrioid), tumor grade (FIGO 3-tiered and 2-tiered), nuclear grade, and risk category (low risk defined as endometrioid histology, grade 1 + 2 and nuclear grade <3). Interrater agreement levels were substantial for identification of nonendometrioid histology (κ = 0.63; SE = 0.025), high tumor grade (κ = 0.64; SE = 0.025), and risk category (κ = 0.66; SE = 0.025). The overall agreement was fair for nuclear grade (κ = 0.21; SE = 0.025). There is agreement amongst pathologists in identifying high-risk pathologic determinants on endometrial cancer biopsies, and these highly correlate with postresection specimens. This is ascertainment prerequisite adaptation of the paradigm shift in surgical staging of patients with endometrial cancer.

Intraoperative margin assessment of the radical trachelectomy specimen.

OBJECTIVE: To summarize our experience in the frozen section (FS) assessment of the trachelectomy surgical margin. METHODS: All surgeries from 1994 to 2007 were performed by one surgeon. The FS examination was consistently carried out by a group of gynecologic pathologists according to the protocol described in details in this article. Cases were retrieved from the pathology files and the slides were reviewed by two pathologists. RESULTS: 132 patients were identified with complete pathology records. They ranged from 17 to 46 years old (median 31). Surgeries were performed for clinical Stages 1A (n=39) and 1B (n=93) tumors (63 adenocarcinoma, 59 squamous cell carcinoma, 7 adenosquamous and 3 others). In 78 cases, no residual tumor was seen in the trachelectomy specimens as it was resected by the preceding LEEP or cone. The margin was reported as negative in 123, suspicious in 3 and positive in 6 cases. It was revised in 16 cases (6 positive, 2 suspicious and 8 negative but <5 mm). Final margin assessment agreed with the FS diagnosis in 130 (98.5%) and showed interpretational overcall in 2 cases (1.5%); only one of which resulted in a revised margin. No false negative intraoperative assessment was found. CONCLUSIONS: We describe our FS protocol and summarize our data. This protocol is reliable since none of the patients was under-treated.

Endocervical reactive atypia: a histologic-cytologic study.

Of 1,500 cervical tissue specimens, 27 cases showed histologic changes of reactive glandular atypia which we defined as endocervical cells with large hyperchromatic, often irregular nuclei, which did not fulfill the criteria for endocervical adenocarcinoma. Eighteen of these 27 cases had preceding or concurrent cervico-vaginal smears. Six of these showed cells which were similar to those seen in histologic sections. The cytologic characteristics of these cells are defined. To determine if atypia is related to inflammatory-regenerative changes, 29 cases of endocervical polyps were examined, of which 11 showed histologic changes of endocervical reactive atypia; 4 showed these changes cytologically as well. Twenty-eight cases of routine hysterectomy specimens were examined, of which 2 cases showed endocervical reactive atypia, which indicated that the atypical changes were indeed reactive. Nine out of 27 cases were associated with hormonal usage. Fourteen cases were associated with squamous intraepithelial lesions or evidence of human papilloma virus. Follow-up of our 27 index cases revealed no progression to adenocarcinoma. These findings indicate that atypia, as we define it, of the endocervix can be due to inflammatory-reparative changes or possibly related to hormonal usage, and permit its separation from precursor lesions of endocervical adenocarcinoma.