A Clinicopathologic Study of Uterine Smooth Muscle Tumours of Uncertain Malignant Potential (STUMP)

Abstract

Introduction: The clinical management of Smooth Muscle Tumours of Uncertain Malignant Potential (STUMPs) remains controversial because little is known about the natural history of these tumours and pathological classifications do not correlate well with clinical outcomes and therefore cannot direct management. The objective of this study was to review a single institution’s experience with STUMP and recommend a rational clinical approach to the management of patients with this histological diagnosis. Materials and Methods: A systematic review of all diagnoses of STUMP and leiomyosarcoma from the gynaecologic oncology and pathology databases between January 1970 and February 2006. Results: A total of 18 diagnoses of STUMP and 72 diagnoses of Ieiomyosarcoma were made during the study period. None of these 72 cases of leiomyosarcoma had a prior diagnosis of STUMP. There were no recurrences in the 18 cases of STUMP with all 18 cases being registered as disease-free after 5 years. Conclusions: We recommend that patients with a diagnosis of STUMP be expectantly managed given the low likelihood of leiomyosarcomatous transformation, the lack of any evidence that adjuvant treatments result in better long-term outcomes and that recurrences are amenable to surgical resection with good outcomes. Key Words: Atypical leiomyoma, Clinical management, Leiomyosarcoma, Malignant transformation

The incidence of neoplasm of uncertain behavior of uterus diagnosed after surgery for presumed leiomyoma: A national population‐based study

“…As shown in Table 2, the median age of women diagnosed with NUBU after surgery was 45 years (IQR 38–49 years), and the incidence of NUBU peaked at 36–45 years and decreased thereafter (Table 2). The median age of NUBU in the present study is comparable to that (41–48 years) of previous studies on NUBU 12–15 . Also, in the previous studies by authors on unsuspected uterine malignancy (UUM) diagnosed after surgery for presumed leiomyoma in the same population, the incidences of UUM diagnosed after hysterectomy, myomectomy, or hysteroscopic myomectomy were 0.19%, 0.12%, and 0.86%, respectively 7–9 .…”

“…Although there are several reports on NUBU diagnosed after surgery for presumed uterine leiomyoma, to our knowledge the present study is the first to report the incidence of NUBU using a large national health insurance database (24 million women annually). [12][13][14][15] In the present study, the incidence of NUBU diagnosed after surgery for presumed leiomyoma was 1.89%. The incidences were 2.03%, 1.84%, and 1.64% for hysterectomy, myomectomy, and hysteroscopic myomectomy, respectively.…”

“…Although there are several reports on NUBU diagnosed after surgery for presumed uterine leiomyoma, to our knowledge the present study is the first to report the incidence of NUBU using a large national health insurance database (24 million women annually) 12–15 …”

“…of previous studies on NUBU. [12][13][14][15] Also, in the previous studies by authors on unsuspected uterine malignancy (UUM) diagnosed after surgery for presumed leiomyoma in the same population, the incidences of UUM diagnosed after hysterectomy, myomectomy, or hysteroscopic myomectomy were 0.19%, 0.12%, and 0.86%, respectively. [7][8][9] The studies reported that the incidence of UUM increased over 50 years.…”

Clinical and reproductive outcomes of uterine smooth muscle tumor of uncertain malignant potential: a single-center retrospective study

“…Only one of 16 patients experienced recurrence of STUMP (6.3%), giving a lower recurrence rate compared with previous reports for STUMP (7.3%-26.7%) and stage I uterine LMS (72.3%). 5,[7][8][9][10][11] The detailed slide review performed during case selection ruled out three patients with sarcomas that were originally reported as STUMP, which might have reduced the recurrence rate. 5,12 Derman et al 13 reported that six of 21 patients with a final diagnosis of STUMP were initially evaluated with equivocal smooth muscle tumors or LMS before pathologic review.…”