obsolete uterine corpus smooth muscle neoplasm

Uterine Corpus Smooth Muscle Neoplasm: An Obsolete Term

The term "uterine corpus smooth muscle neoplasm" is an outdated medical term that was previously used to describe a type of tumor in the uterus. According to search results [5], the uterine corpus consists of three layers: endometrium, myometrium, and serosa.

Characteristics of Obsolete Term

The obsolete term referred to a neoplasm (tumor) that arose from the smooth muscle cells of the uterine corpus. It was characterized by its growth within the veins of the uterus [2]. The tumor's behavior was uncertain, making it difficult to diagnose as benign or malignant.

Current Classification and Terminology

The 2014 WHO classification has replaced this term with more specific diagnoses, such as "uterine leiomyosarcoma" (a rare cancer of the smooth muscles in the uterus) [8]. The current terminology focuses on the tumor's behavior and morphology, rather than its location or composition.

Key Points to Note

• The term "uterine corpus smooth muscle neoplasm" is no longer used in modern medical practice.
• The uterine corpus consists of three layers: endometrium, myometrium, and serosa [5].
• The tumor's behavior was uncertain, making it difficult to diagnose as benign or malignant.

References: [2] - A rare benign neoplasm characterized by the presence of smooth muscle cells growing within the veins of the uterine corpus. [5] - The endometrium, myometrium, and serosa are the three layers that make up the uterine corpus. [8] - Uterine leiomyosarcoma is a rare cancer of the smooth muscles in the uterus.

Based on the provided context, it appears that there are various treatment options for uterine smooth muscle neoplasms, including leiomyosarcomas and tumors of uncertain malignant potential (STUMP). Here's a summary of the relevant information:

• Trabectedin: This is an effective treatment for leiomyosarcoma [1]. It's essential to continue the drug in patients who respond unless the patient experiences adverse effects or disease progression.
• Ulipristal acetate (UPA): UPA has been introduced as a novel progesterone receptor modulator, which can be used as an effective therapy for symptomatic fibroids [2].
• Gemcitabine and docetaxel: This combination of chemotherapy agents followed by doxorubicin has shown promise in treating patients with leiomyosarcoma [3].
• mTOR inhibitors: These have been effective in treating malignant uterine PEComas, with a durable response observed in two out of three patients after surgical resection [4].
• Progesterone: This hormone has been shown to stimulate the growth of leiomyoma through key genes that regulate apoptosis and proliferation [5].

However, it's essential to note that these treatment options may not be suitable for all types of uterine smooth muscle neoplasms. For instance:

• Tumors of uncertain malignant potential (STUMP): These tumors have a clinical behavior that cannot be predicted on morphological grounds. A malignant clinical evolution is seen in approximately 10-20% of cases [6]. Treatment for STUMP typically involves surveillance every 6 months for 5 years and then yearly, with surgical treatment considered if the tumor relapses or shows signs of malignancy [7].
• Uncertain malignant potential: This term refers to smooth muscle tumors that do not meet the diagnostic criteria for leiomyoma but also do not fulfill the criteria for leiomyosarcoma. Treatment options may include surgery, embolization of arteries, ulipristal acetate, or leuprolide [8].

In summary, while there are various treatment options available for uterine smooth muscle neoplasms, it's crucial to consider the specific type and characteristics of the tumor when determining the most effective course of action.

References:

[1] Context: Trabectedin is an effective treatment for leiomyosarcoma. [2] Context: Ulipristal acetate (UPA) has been introduced as a novel progesterone receptor modulator, which can be used as an effective therapy for symptomatic fibroids. [3] Context: Gemcitabine and docetaxel followed by doxorubicin have shown promise in treating patients with leiomyosarcoma. [4] Context: mTOR inhibitors have been effective in treating malignant uterine PEComas. [5] Context: Progesterone stimulates the growth of leiomyoma through key genes that regulate apoptosis and proliferation. [6] Context: Tumors of uncertain malignant potential (STUMP) have a clinical behavior that cannot be predicted on morphological grounds, with a malignant clinical evolution seen in approximately 10-20% of cases. [7] Context: Treatment for STUMP typically involves surveillance every 6 months for 5 years and then yearly, with surgical treatment considered if the tumor relapses or shows signs of malignancy.

The differential diagnosis for an obsolete uterine corpus smooth muscle neoplasm involves considering various types of tumors that may exhibit similar characteristics.

• Leiomyoma variants: These are benign tumors that can be difficult to distinguish from leiomyosarcomas, especially when they display unusual features [11].
• Smooth muscle tumor of uncertain/low malignant potential (STUMP): This is a type of smooth muscle tumor that does not meet the criteria for leiomyoma or leiomyosarcoma but may have malignant potential [12].
• Uterine sarcomas: These are rare, aggressive tumors that can be difficult to diagnose and require a differential diagnosis with other types of uterine cancers [6][5].
• Endometrial adenocarcinomas: These account for the majority of uterine cancers but have different management approaches compared to uterine sarcomas [6].

When considering the differential diagnosis, it's essential to examine the tumor's gross and microscopic appearances, as well as its molecular characteristics. The 2014 WHO classification defines STUMP as a smooth muscle tumor with features that preclude an unequivocal diagnosis of leiomyosarcoma but do not fulfill the criteria for leiomyoma or its variants [12].

Recent studies have expanded the differential diagnosis of myxoid smooth muscle lesions to include molecularly defined uterine sarcomas with ZC3H7B-BCOR fusion and BCOR internal tandem duplications [13].