Leiomyosarcoma differential diagnosis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Nima Nasiri, M.D.[2]

Overview

Leiomyosarcoma must be differentiated from other soft tissue tumors, some variants of leimyoma resembles malignant tumor. Other possible differential diagnosis of leimyosarcoma include, epithelioid endometrial stromal sarcoma, alveolar soft part sarcoma, epithelioid angiosarcoma, pleomorphic rhabdomyosarcoma.

Differentiating Leiomyosarcoma from other Diseases

The table below summarizes the findings that differentiate Leiomyosarcoma from other conditions that may cause similar signs and symptoms.

Diseases	Clinical manifestations		Para-clinical findings					Gold standard	Additional findings
	Symptoms	Physical examination
			Lab Findings	Imaging			Histology
				Ultrasound	CT scan	MRI
Uterine Leiomyosarcoma	Abnormal vaginal bleeding (Postmenopausal or intermenstrual bleeding or bleeding from uterus or vagina) Pressure or pain pelvic or abdomen Vaginal dyscharge Change in bladder or bowel habits Fatigue Fever Malaise Weight loss	Lump protruding from vagina Mass in abdomen or pelvic Tendenrness on palpating pelvic or Abdomen Lymphadenopathy	↓ RBC or Hemoglobin may be seen on CBC. In uterine leiomyosarcomas (LMSs) p16 is overexpressed compared with leiomyoma.	Deep myometrial invasion	Massive uterine enlargement Irregular central zones of low attenuation, Extensive necrosis and hemorrhage	Features such as tumor localization, irregular or nodular margins, necrosis, rapid growth, intense contrast enhancement, and restriction at diffusion-weighted imaging can suggest the diagnosis and help differentiate from more common leiomyomas and endometrial carcinoma.	Gross histology: Large, solitary, poorly circumscribed masses (average 10 cm) Typically display a fleshy variegated cut surface with areas of hemorrhage or necrosis	Histology and biopsy	Women with sarcoma vs women with fibroids, tend to be older More likely to be postmenopausal More likely to have a history of another nonuterine malignancy Women with sarcoma were more likely to have masses that are subserosal Solitary rather than multiple uterine mass
Leimyoma (mitotically active type)	Vaginal bleeding Pelvic pain		CBC suggestive of anemia Bcl-2 expression is more frequent and strong marker in leiomyomas compared with leiomyosarcoma.	Enlarged uterus with multiple whorled mass lesions, largest of size 8.6×7.1 cm, not extending into the abdomen	An enlarged uterus and a deformed uterine contour are the most common CT findings of leiomyomas Leiomyomas usually have a uniformly solid consistency		Abscence of cytologic atypia Mild nuclear atypia, up to 10-20 mitosis No tumor cell necrosis	Biopsy and histology	-
Hemorrhagic cellular leiomyomas (apoplectic leiomyoma)	Abdominal pain				-	-	On microscopic analysis: Zones of recent hemorrhage within nodules of hypercellular smooth muscle. Coagulative necrosis (red degeneration) Mitotic figure not exceeding 2/10 HPF, mostly located in the perihemorrhagic areas On gross examination: Features of multiple hemorrhagic area Necrosis Cyst formation Softening, or color different than the usual leiomyoma	Biopsy specimen and histology
PEComa	Palpable abdominal masses Abnormal vaginal bleeding Flank pain (kidneys) Dull abdominal pain in right upper quadrant (liver)		PECs typically stain for melanocytic markers (HMB-45, HMSA-1, Melan A (Mart 1), microophthalmia transcription factor (Mitf), myogenic markers (actin), and less commonly desmin		Mean tumor diameter of 5 cm, well-defined margins, hypodense mass	Low and high signal intensity on T1- and T2-weighted MRI Strong, heterogeneous enhancement			Association with lymphangiomyomatosis and tuberous sclerosis
Epitheloid angiosarcoma	Painful, enlarging soft tissue masses Long bone fractures Arteriovenous shunting and subsequent high-output cardiac failure symptoms such as dypnea on exertion.						Microscopic histology: Nodules, and trabeculae of infiltrative epithelioid to spindled cells Eosinophilic cytoplasm.