Prognostic Value of the Diagnostic Criteria Distinguishing Endometrial Stromal Sarcoma, Low Grade From Undifferentiated Endometrial Sarcoma, 2 Entities Within the Invasive Endometrial Stromal Neoplasia Family

Abstract

Summary:The World Health Organization (WHO 2003) recognizes 3 endometrial stromal neoplasms: noninvasive endometrial stromal nodule and the 2 invasive neoplasms, endometrial stromal sarcoma (ESS), low grade and undifferentiated endometrial sarcoma (UES). It is important to note that the WHO 2003 does not define moderate atypia (an important differentiating diagnostic criterion for ESS, low grade and UES), nor does it discuss its significance. Moreover, studies on reproducibility and additional prognostic value of other diagnostic features in large are lacking. Using strict definitions, we analyzed the agreement between routine and expert-review necrosis and nuclear atypia in 91 invasive endometrial stromal neoplasias (IESN). The overall 5-year and 10-year recurrence-free survival rate estimates of the 91 IESN patients were 82% and 75%, respectively. Necrosis was well reproducible, and nuclear atypia was reasonably well reproducible. The 10-year recurrence-free survival rates for necrosis absent/inconspicuous versus prominent were 89% and 45% (Po0.001) and those for review-confirmed none/mild, moderate, severe atypia were 90%, 30%, and o20% (Po0.00001). Therefore, cases with moderate/severe atypia should be grouped together. Nuclear atypia and necrosis had independent prognostic values (Cox regression). Once these features were taken into account, no other feature had an independent additional prognostic value, including mitotic count. Using ''none/

Can Proliferation Biomarkers Reliably Predict Recurrence in World Health Organization 2003 Defined Endometrial Stromal Sarcoma, Low Grade?

“…Such problems do not exist with the two essential diagnostic WHO2003 characteristics, the degree of atypia and extent of necrosis. The advantage of these criteria compared to mitosis counts and the fact that the classification is well reproducible and strongly prognostic [23] makes clear that the WHO2003 classification can be an improvement.…”

“…Details for the patients have been described elsewhere [23], [25]. Medical records and microscopic sections of all tumors diagnosed as low and high grade endometrial stromal sarcoma (old classification) between 1992 and 2007 were retrieved from the FUOGH Gynecology and Pathology Department files.…”

“…To further study this hypothesis, we have investigated WHO2003 defined ESS-LG with reasonably long term follow-up (median: 53, range: 24–83) [23] to identify features that are independently prognostic. The present study examines the value and limitations of nuclear proliferation markers, including mitoses counted in traditional haematoxyllin and eosin (H&E) stained microscopic sections, Ki-67 (sometimes called MIB-1 after the antibody for the staining of Ki-67 in paraffin sections) [21], [24] and a newer antibody that targets a nuclear antigen called PhosPhoHistone-3 (PPH3).…”

Recent Developments in Surgical Pathology of the Uterine Corpus

“…6 High-grade ESS is now defined as a tumor composed of atypical cells resembling endometrial stromal cells but lacking the degree of atypia and pleomorphism of UUS (Figure 8). 44,45 The separate identity of this high-grade ESS was further confirmed by a specific YWHAE-FAM22 gene rearrangement. 46 Undifferentiated uterine sarcomas are now defined as high-grade sarcomas lacking evidence of endometrial stromal morphology combined with severe cytologic atypia, often with multinucleated and bizarre cells and brisk mitotic activity (.20 mitoses/10 HPFs).…”

Stages I to II WHO 2003–Defined Low-Grade Endometrial Stromal Sarcoma: How Much Primary Therapy Is Needed and How Little Is Enough?

“…3 The WHO 2003 classification is not just a name change, and as many as 15% of cases previously classified as LGESS are now UES. 4 Moreover, the prognosis of low-grade ESS is much better than the pre- 2003 LGESS. In contrast to the preYWHO 2003 LGESS, which could have as many as 20% to 35% recurrences, 5 low-grade ESS has an indolent behavior, with 5 and 10 years' survival rates of 90% and higher, with a low frequency of late recurrence and distant metastases.…”