Human health and medicine

Leiomyoma of uterus

Leiomyoma (uterine fibroid, myoma) is a benign smooth muscle tumor of the uterus, the most common uterine tumor, affecting over half of women over 45; treated with medication, myomectomy, embolization, or hysterectomy.

Leiomyosarcoma

Leiomyosarcoma, or lyomyosarcoma, is an aggressive cancerous tumor of smooth muscle cells that can arise almost anywhere, most often in the uterus, abdomen, or pelvis.

Leiomyosarcoma of small intestine

Leiomyosarcoma of the small intestine, a rare smooth-muscle sarcoma most often in the ileum, distinguished from GIST by SMA/desmin positivity and CD117/DOG1 negativity; treated mainly by surgical resection.

Leiomyosarcoma of stomach

Gastric leiomyosarcoma, a rare malignant smooth muscle tumor of the stomach (under 1% of gastric malignancies), distinguished from GIST by desmin/SMA positivity and CD117/DOG1 negativity; treated mainly by complete surgical excision.

Leiomyosarcoma of the cervix uteri

Leiomyosarcoma of the cervix uteri (cervical leiomyosarcoma, CLMS) is a rare malignant smooth-muscle tumor of the cervix, 21% of cervical sarcomas, with under 40 reported cases; hysterectomy is first-line treatment.

Oct 20, 2026

Leishmaniosis

Leishmaniosis (leishmaniasis), infection with Leishmania protozoa spread by female phlebotomine sand flies; forms are visceral (kala-azar), cutaneous, and mucocutaneous; WOAH-listed in dogs and cats, diagnosed by PCR, serology, and parasitology.

Lelis syndrome

Lelis syndrome, or ectodermal dysplasia-acanthosis nigricans syndrome (OMIM 608290), is a rare autosomal recessive disorder with hypotrichosis, hypohidrosis, acanthosis nigricans, palmoplantar hyperkeratosis, nail dystrophy, hypodontia, and intellectual deficit; named for Lithuanian dermatologist Jonas Lelis.

Lemierre's syndrome

Lemierre's syndrome, also called postanginal sepsis or necrobacillosis, is septic thrombophlebitis of the internal jugular vein with septic emboli after oropharyngeal infection, usually Fusobacterium necrophorum, in adolescents and young adults.

Lemzoparlimab

Lemzoparlimab (TJC4, TJ011133) is a fully human IgG4 anti-CD47 monoclonal antibody from I-Mab Biopharma that binds a distinct glycosylation-shielded epitope to spare red blood cells; development was halted outside China in 2022 and its phase III MDS trial discontinued in 2025.

Lenabasum

Lenabasum (ajulemic acid, JBT-101, anabasum, Resunab) is a synthetic oral CB2 receptor agonist, nonpsychoactive, developed by Corbus for inflammatory and fibrotic diseases; Phase 2 trials in systemic sclerosis and dermatomyositis were positive, but Phase 3 dermatomyositis and CF programs failed, and it is unapproved.

Oct 20, 2026

LENABC trial

LENABC (NCT04656249) is a completed phase 2 trial of lenvatinib in previously treated advanced biliary tract cancer, sponsored by Peking Union Medical College Hospital; no results have been posted on ClinicalTrials.gov.

Lenalidomide

Lenalidomide (Revlimid), an oral thalidomide-analogue IMiD, treats multiple myeloma, del(5q) MDS, and lymphomas by binding cereblon to degrade IKZF1/IKZF3; US approval 2005, REMS-restricted, with resistance via CRBN lesions.

Lenalidomide/low-dose dexamethasone regimen

The lenalidomide/low-dose dexamethasone regimen (Rd) is an oral, chemotherapy-free doublet for multiple myeloma, pairing lenalidomide with once-weekly dexamethasone, established as standard first-line therapy by the FIRST trial.

Lenercept

Lenercept (Ro 45-2081, Tenefuse) was a Roche recombinant p55 TNF receptor-IgG1 Fc fusion protein tested in rheumatoid arthritis, multiple sclerosis, and sepsis; development was discontinued after transient RA efficacy and a failed MS trial.

Length of Stay

Length of Stay (LOS) is the number of days a patient remains in a hospital between admission and discharge, widely used as a measure of hospital utilization and efficiency.

Leniolisib

Leniolisib (Joenja, CDZ173) is an oral PI3Kδ inhibitor, FDA-approved March 2023 as the first treatment for activated PI3K delta syndrome (APDS), dosed 70 mg twice daily, with high δ selectivity and lower potency than oncology PI3K inhibitors.

Lennox–Gastaut syndrome

Lennox–Gastaut syndrome (LGS) is a severe childhood-onset epilepsy with multiple drug-resistant seizure types, slow spike-and-wave EEG, intellectual disability, and treatments including valproate, lamotrigine, rufinamide, cannabidiol, callosotomy, and vagus nerve stimulation.

Lenograstim

Lenograstim (Granocyte, Neutrogin) is a glycosylated recombinant human G-CSF made in CHO cells, approved in Europe in 1993, used for chemotherapy-induced neutropenia, transplantation support, and progenitor cell mobilization; not FDA-approved.

Lenox Hill Hospital

Lenox Hill Hospital, founded 1857 as the German Dispensary, renamed 1918, is a Northwell Health teaching hospital on Manhattan's Upper East Side at 100 East 77th Street, with a 5-star CMS rating and a $2 billion expansion approved in 2025.

Lensectomy

Lensectomy is the surgical removal of the eye's crystalline lens, performed through the pars plana rather than routine corneal incisions, for unstable, subluxated, or displaced lenses.

Lentigo

Lentigo (plural lentigines) is a benign pigmented skin lesion with increased basal melanocytes, unlike a freckle (ephelis). Main types are lentigo simplex and solar lentigo (liver spots) from UV exposure.

Lenvatinib plus pembrolizumab

Lenvatinib plus pembrolizumab is a combination cancer therapy pairing the oral kinase inhibitor lenvatinib with the anti–PD-1 antibody pembrolizumab, FDA-approved for advanced renal cell carcinoma and endometrial carcinoma.

Lenvatinib regimen

A lenvatinib regimen is an oral cancer treatment built around lenvatinib, a once-daily tyrosine kinase inhibitor given alone or with pembrolizumab, everolimus, or belzutifan for thyroid, liver, kidney, and endometrial cancers.

Lenz-Majewski hyperostotic dysplasia

Lenz-Majewski hyperostotic dysplasia (Lenz-Majewski syndrome, LMHD) is an ultra-rare autosomal dominant bone dysplasia caused by gain-of-function PTDSS1 variants, with craniotubular hyperostosis, cutis laxa, intellectual disability, and about 23 reported cases.