Pseudotumors and Cysts Assoc Professor Jan Laco MD

Pseudotumors and Cysts Assoc. Professor Jan Laco, MD, Ph. D

Causes of swellings of jaws • Cysts – odontogenic x non-odontogenic • • • Odontogenic tumors Giant cell lesions Fibro-osseous lesions Non-odontogenic tumors of bone Metastatic tumors Chronic osteomyelitis

Cysts of jaws • • = pathological cavity lined by epithelium RTG: sharply-defined lucencies ± fluid slowly growth teeth displacement asymptomatic x infection painfull rarely: pathological fracture compressible and fluctuant swelling if extending into soft tissues • appear bluish when close to mucosal surface

Cysts of jaws • Odontogenic – developmental • • • dentigerous eruption gingival lateral periodontal odontogenic keratocyst calcifying odontogenic cyst – inflammatory • radicular / residual • inflammatory collateral (paradental)

Cysts of jaws • Non-odontogenic – nasopalatine duct – nasolabial – surgical ciliated cyst • Pseudocysts – solitary bone “cyst“ – aneurysmal bone “cyst“ – Stafne´s “cyst“

Cysts of jaws – frequency (%) • • 1. radicular 2. dentigerous 3. keratocyst 4. nasopalatine 65 -70 15 -20 10 -20 5 -10

Radicular cyst • • • most common swelling of jaws / cyst males (M : F … 3 : 2) 20 - 60 years maxilla : mandible … 3 : 1 painless swelling enucleation

Radicular cyst • at tip of root of tooth with necrotic pulp (caries) • pulpitis periodontitis periapical granuloma proliferation of Malassez nests central liquefaction • Mi: hyperplastic non-keratinizing squamous epithelium (net-like) ± hyaline (Rushton) bodies wall: granulation tissue + fibrous tissue mixed inflammation hemosiderin, cholesterol clefts ± granulomas

Odontogenic cysts • residual cyst – radicular cyst left behind after tooth extraction – spontaneous regress • lateral radicular cyst – at side of nonvital tooth – lateral branch of root canal – enucleation

Inflammatory collateral cyst • inflammation around partially erupted tooth • paradental cyst: lower M 3 • mandibular buccal bifurcation cyst: lower M 1 and M 2 • males, children or adults aged 20 - 25 years • vital tooth with pericoronitis • Mi: ~ radicular cyst • enucleation

Dentigerous (follicular) cyst • cystic change of enamel organ after complete enamel formation • fluid accumulation between crown and collapsed enamel organ • surrounds crown + attached to tooth neck at amelo -cemental junction crown inside (RTG) • M: F… 2: 1 • 20 - 50 years • mandibular M 3, maxillary C prevents eruption • Mi: thin squamous epithelium (2 -3 layers) fibrous wall with scanty inflammation

Eruption cyst • • • in soft tissue over tooth about to erupt from enamel organ (superficial dent. cyst) children teeth with no predecessors soft bluish swelling in gingiva spontaneously disappear

Gingival cysts • • newborns (Bohn´s nodules) > 80 % of newborns gingiva - proliferation of Serres nests spontaneously resolve in months • midline of palate (Epstein´s pearls) • adults - rare

Lateral periodontal cyst • • uncommon cyst beside vital tooth from nests of Malassez ? mandibular premolars Mi: thin squamous epithelium + plaque-like thickenings with clear cells (glycogen)

Lateral periodontal cyst - variants • botryoid odontogenic cyst – multilocular variant of LPC – lower P and C, may occupy major parts of jaw, > 50 years – Mi: multilocular cyst with fibrous septa squamous epithelium + clear cells (glycogen) – recurrence (20 %)

Glandular odontogenic cyst (sialo-odontogenic) – multilocular cyst – Mi: complex squamous epithelium ~ LPC and BOC + mucous cells + intraepithelial glandular spaces – recurrence (30 -50 %) – diff. dg. : intraosseous mucoepidermoid carcinoma

Odontogenic cysts • • WHO classification 2005 WHO 2017 odontogenic keratocystic odontogenic tumor odontogenic keratocyst • calcifying odontogenic cyst • calcifying cystic odontogenic tumor • calcifying odontogenic cyst

Odontogenic keratocyst • • • 3 rd most common cyst of jaw M > F; ~ 20 -30 Y + 50 -70 Y angle of mandible (80 %) RTG: multilocular cyst Mi: cyst – thin squamous epithelium (5 -8 layers) with wavy parakeratosis ± tiny daughter cysts in wall • PTCH 1 gene alteration • recurrence (2 -25 %) within first 5 years !!! • treatment: complete enucleation

Odontogenic keratocyst • Gorlin-Goltz syndrome – AD; PTCH gene 9 q 22. 1 -31; complete penetrance; 1 : 60, 000 – multiple KOT + “naevoid“ basal cell carcinomas + skeletal abnormalities + ectopic calcifications + various tumors + ocular defects • Orthokeratotic cyst – – rare RTG: monolocular cyst Mi: orthokeratotic layer recurrence 4 %

Calcifying odontogenic cyst • • = Gorlin´s cyst M ~ F, ~ 5 - 92 Y mandible ~ maxilla, incisor-cuspid area, gingiva Mi: cyst lined by ameloblastic epithelium ghost cells calcification dentin • recurrence (5 %) • sometimes association with ameloblastoma • treatment: enucleation

Odontogenic cysts • RTG diff. dg. of jaw radiolucency – anatomical structures (maxillary sinus, foramina) – odontogenic cysts – odontogenic tumors, part. ameloblastoma – giant cell granuloma / cherubism • wall thickenings – cholesterol clefts + granulomas – carcinoma – ameloblastoma

Odontogenic cysts • daily biopsy practice • nonspecific findings – inflammation !!! • • x odontogenic keratocyst x calcifying odontogenic cyst x unicystic ameloblastoma x other cystic tumors

Nasopalatine duct cyst • • uncommon, often asymptomatic from nasopalatine duct epithelium midline of palate position variants (to incisive canal) – nasopalatine – palatine papilla – median alveolar • Mi: squamous + respiratory epithelium wall: mucous glands + neurovascular bundle • enucleation

Nasolabial cyst • • • = Klestadt´s, nasoalveolar very uncommon middle-aged females from remnants of nasolacrimal duct in soft tissue deep in nasolabial fold excision

Surgical ciliated cyst • • • maxilla site of injury or operation (incl. extraction) Caldwell-Luc surgery cyst lining = mucosa of maxillary sinus respiratory epithelium enucleation

Cysts of soft tissues • thyroglossal duct cyst • lymphoepithelial cyst • lingual dermoid • mucocele

Thyroglossal duct cyst • • uncommon from remnants of any part of thyroglossal duct early age swelling in midline of mouth (foramen caecum) or neck • Mi: squamous + respiratory epithelium wall: thyroid tissue, chronic inflammation • removal + part of hyoid bone

Lymphoepithelial cyst • • branchiogenic cyst ? ? ? cystic change of epithelium entrapped in LN early age lateral part of neck + mandible angle + parotid soft swelling fistula to skin / oral cavity / pharynx Mi: squamous + respiratory epithelium wall: dense lymphoid tissue + germ centres • enucleation • diff. dg. : cystic metastasis of SCC !!!

Sublingual dermoid • developmental anomaly of branchial arches or pharyngeal pouches • between hyoid and jaws or beneath tongue • no symptoms • Mi: epidermoid cyst – NO dermal appendages dermoid cyst – dermal appendages • dissection

Mucoceles • • minor salivary glands lower lip superficial, 1 cm swellings extravasation type – damage of duct – saliva leak inflammation + mucophages – NO epithelium mucofagic granuloma • retention type – obstruction of duct – epithelium of dilated duct

Mucoceles • ranula (Lat. “small frog“) = mucocele of submandibular or sublingual gland • unilateral painless swelling, 2 -3 cm • floor of mouth