Rare anatomical localizations of hydatid cysts (2020-2025): Narrative review of presentation, imaging, and management

Unusual localizations of hydatid cysts-such as the brain, spine, heart, bone, retroperitoneum, spleen, and musculature-are relatively rare but clinically important due to their non-specific presentations, diagnostic ambiguity, and increased risk of surgical complications (4,5).These atypical manifestations often mimic malignancies, abscesses, or congenital cysts, leading to delayed or inappropriate interventions (6).From a general surgery standpoint, such cases demand heightened suspicion and careful planning to minimize perioperative morbidity and recurrence risk.Recent literature has reported an increase in the detection of extrahepatic and extrapulmonary hydatid cysts, likely owing to advances in imaging technologies and improved clinical awareness (7).However, there remains a lack of consensus on the diagnostic and therapeutic approach to these rare presentations.While surgical excision remains the cornerstone of treatment, particularly in complicated or inaccessible locations, the roles of minimally invasive procedures and adjunctive antiparasitic therapy continue to evolve (8,9). ABSTRACTHydatid disease, caused by Echinococcus granulosus, typically affects the liver and lungs.However, cyst development in rare anatomical sites presents unique diagnostic and therapeutic challenges.We conducted a narrative review using a structured search of PubMed, Scopus, and Google Scholar (first 200 records), with predefined eligibility criteria and dual-reviewer screening where applicable.Findings were synthesized narratively; numeric summaries reflect reporting frequency among included case-level reports rather than prevalence or comparative effectiveness.Seventeen studies (case reports/small series) were included.Among the included reports, the most commonly reported rare sites were the brain, bone, and heart.Imaging narratives most frequently supported magnetic resonance imaging triage for central nervous system/spine/cardiac disease and computed tomography for osseous/retroperitoneal involvement, while surgery was most often reported as the index treatment with context-dependent use of albendazole.Percentages in this review reflect the share of reports among included studies (i.e., reporting frequency), not population prevalence, incidence, or comparative effectiveness.Rare-site hydatid cysts require a high index of suspicion in endemic areas.Optimal outcomes are achieved through multidisciplinary evaluation, site-specific surgical planning, and tailored pharmacotherapy.Further research into minimally invasive techniques, molecular diagnostics, and vaccine development is warranted to improve diagnosis and long-term disease control.