AI Research Rounds – Solid Odontogenic Keratocyst

Research Date: 2026-05-06
Research Question: Solid odontogenic keratocyst: clinical presentation, diagnosis, treatment, prognosis, and relationship with OSCC — a comprehensive clinical review
Method: AI-assisted systematic review (Ralph Loop + Multi-Agent Architecture)
Report Version: 1.0
Language: English

Executive Summary

Clinical Bottom Line

"Solid odontogenic keratocyst (SOKC)" is an extremely rare and poorly defined entity that likely represents the same disease spectrum as keratoameloblastoma. The term "solid OKC" in clinical practice more commonly refers to OKCs presenting with solid components on imaging or multilocular radiographic patterns (~30% of all OKCs). These lesions are more aggressive than unilocular OKCs, with higher recurrence rates, and warrant a stepped treatment approach — decompression followed by enucleation with adjunctive therapy (5-FU or modified Carnoy’s) for most cases, and radical resection for recurrent, perforated, or syndromic lesions. Malignant transformation to OSCC is rare (~1-2/1,000) but carries a poor prognosis and must be considered in the differential diagnosis.

Key Numbers

Metric Value Evidence Level
Multilocular OKC prevalence ~30% of all OKCs (up to 72% in large mandibular lesions) Moderate (+++○)
Recurrence after enucleation alone 17–56% High (++++)
Recurrence after enucleation + 5-FU ~8.3% at 14 months Low (++○○)
Recurrence after resection <2% Moderate (+++○)
Malignant transformation (OKC→OSCC) 1–2 per 1,000 Low (++○○)
BRAF V600E in SOKC/OKC 0% (consistently negative) High (++++)
PTCH1 mutation in SOKC Present (confirmed) Low (++○○)

Scope Statement

What This Is

  • AI-assisted literature synthesis using systematic methodology
  • Rapid evidence review with transparent process
  • Clinical decision support tool for oral and maxillofacial surgeons
  • Transparent documentation of methods and limitations

What This Is NOT

  • Formal systematic review (not registered in PROSPERO)
  • Meta-analysis
  • Clinical practice guideline
  • Peer-reviewed publication
  • Replacement for clinical judgment or institutional protocols

Intended Audience

Oral and maxillofacial surgeons, head and neck surgeons, oral pathologists, oral medicine specialists, OMFS residents

Main Findings

1. Definition, Classification, and Epidemiology

Conclusion: "Solid variant of odontogenic keratocyst (SOKC)" is an extremely rare, poorly defined lesion not recognized as a distinct entity in the WHO classification. SOKC and keratoameloblastoma (KAB) likely represent the same disease. In broader clinical usage, "solid OKC" refers to OKCs with multilocular radiographic appearance (~30%) or those with solid soft-tissue components on CT/MRI.

Evidence:

Study Design n Key Finding GRADE
Zhang 2021 Case series + molecular 9 SOKC and KAB overlap; PTCH1+ BRAF- ++○○
Cavarra 2022 Pictorial review — ~30% OKCs multilocular; soap-bubble appearance +++○
Slusarenko da Silva 2021 Meta-analysis 13 studies OKC p53 expression similar to ameloblastoma ++++

WHO Classification History:

  • Pre-2005: OKC = developmental cyst
  • 2005: Reclassified as KCOT (neoplasm)
  • 2017: Reverted to OKC (cyst)
  • 2022: Maintained as cyst; SOKC still unaddressed

Clinical Implication: When a patient presents with a multilocular/solid jaw lesion, SOKC should be on the differential, but the diagnosis requires histopathology with BRAF V600E IHC to exclude ameloblastoma.

2. Clinical Presentation and Imaging

Conclusion: Solid/multilocular OKCs tend to be larger and more aggressive than unilocular OKCs, often presenting as slowly progressive swelling. On imaging, DECT can help differentiate OKCs with solid components from ameloblastoma preoperatively.

Evidence:

Study Design n Key Finding GRADE
Jiang 2026 Retrospective 48 (28 AM, 20 OKC) DECT quantitative parameters distinguish AM from OKC with solid components ++○○
Satish 2025 Prospective 50 72% multilocular; decompression effective ++○○
Nasarudin 2025 Retrospective 147 Peak 3rd decade; mandibular predominance +++○
Davra 2025 Case report 1 "Clinically silent" solid-cystic OKC, 20-year history +○○○

Radiographic Features:

  • Well-defined radiolucency with corticated margins
  • Multilocular: "soap-bubble" appearance with satellite cysts
  • Minimal tooth root resorption (vs ameloblastoma)
  • Grows along medullary cavity (anteroposterior)
  • DECT: iodine concentration and effective atomic number differ from ameloblastoma

Differential Diagnosis of Solid/Multilocular Jaw Lesions:

  1. Ameloblastoma (solid/multicystic type)
  2. Odontogenic myxoma
  3. Central giant cell granuloma
  4. Aneurysmal bone cyst
  5. Glandular odontogenic cyst
  6. OSCC (especially with cortical perforation)

Clinical Implication: Preoperative DECT and AI-assisted CT analysis (Nomoto 2026) can improve diagnostic accuracy, but biopsy remains essential. BRAF V600E IHC is the key discriminator from ameloblastoma.

3. Histopathology and Diagnostic Criteria

Conclusion: SOKC is diagnosed by the presence of predominantly solid odontogenic epithelial proliferation with parakeratinization, palisaded basal cells, and keratin pearl formation. BRAF V600E negativity and PTCH1 mutation positivity support the diagnosis.

Proposed Diagnostic Criteria:

  • Major: Solid epithelial proliferation, parakeratinization, palisaded basal cells, BRAF V600E negative, PTCH1 mutation
  • Minor: Keratin pearls, absence of ameloblastic differentiation, satellite cysts, elevated Ki-67
  • Exclusion: BRAF V600E positive → ameloblastoma

Key Immunohistochemical Profile:

Marker SOKC/OKC Ameloblastoma
BRAF V600E Negative Positive (~80%)
PTCH1 Mutated Not mutated
Ki-67 Elevated (suprabasal) Higher overall
p53 Positive Positive
CK10/CK17 Positive Variable

Critical Finding — OKC→SOKC Transformation:
Yamasaki et al. (2024) documented transformation of a classic cystic OKC into SOKC/KA upon recurrence. This suggests SOKC may represent phenotypic progression of conventional OKC.

Clinical Implication: Any OKC specimen with solid areas should undergo BRAF V600E IHC. If negative, PTCH1 testing can confirm OKC lineage. Documented transformation risk reinforces the need for complete initial removal.

4. Treatment

Conclusion: A stepped approach is recommended: decompression for large lesions → enucleation + adjunctive therapy (5-FU preferred, or modified Carnoy’s) → radical resection for recurrent, perforated, or syndromic lesions.

Treatment Algorithm:

Solid/Multilocular OKC Diagnosed
│
├─ Small-to-moderate (<5 cm), no cortical breach
│  → Enucleation + peripheral ostectomy + 5-FU OR Modified Carnoy's
│
├─ Large (>5 cm), cortical intact or thinned
│  → Decompression (3–12 months) → Delayed enucleation + adjunctive
│
└─ Cortical perforation, recurrent, syndromic, suspicious for malignancy
   → Marginal or segmental resection with 1 cm margins

Adjunctive Therapies:

  • 5-Fluorouracil (5-FU): Emerging as preferred adjunct. Mahmoud et al. (2025) systematic review supports efficacy. Yi et al. (2025): 8.3% recurrence at 14 months with topical 5-FU.
  • Modified Carnoy’s Solution: Effective but 5-FU increasingly favored due to safety profile. Garg et al. (2026) demonstrates versatility.
  • Peripheral ostectomy: Piezotome-assisted removal of 1–2 mm peripheral bone (Abdelfadil 2025).
  • Radical resection: Bushabu et al. (2023) — indications include multilocular presentation, cortical perforation, recurrence, syndromic association, and suspected malignancy.

Clinical Implication: Solid/multilocular presentation is itself an indication for more aggressive treatment. Enucleation alone is insufficient.

5. Recurrence and Prognosis

Conclusion: Recurrence rates range from 2.5% to 62%, with multilocular/solid variants at the higher end. Treatment modality is the single strongest prognostic factor. Minimum 5-year follow-up is mandatory; recurrence can occur after 10+ years.

Recurrence by Treatment:

  • Enucleation alone: 17–56%
  • Enucleation + Carnoy’s: 1–8%
  • Enucleation + peripheral ostectomy: 5–12%
  • Decompression + enucleation: 8–15%
  • Resection: <2%

Prognostic Factors (Bera 2024):

  1. Multilocular/solid locularity — higher risk
  2. Cortical perforation
  3. Satellite/daughter cysts
  4. Treatment modality (strongest factor)
  5. Syndromic association (NBCCS)
  6. Age < 30
  7. Previous recurrence

Follow-up Protocol:

  • Minimum 5 years (extend to 10+ for high-risk cases)
  • Panoramic radiograph every 6 months (first 2 years), then annually
  • CBCT at 1, 3, 5 years for solid/multilocular cases
  • Higher intensity for syndromic, recurrent, and large lesions

Clinical Implication: Recurrent OKCs may transform to SOKC phenotype. Long-term follow-up is essential.

6. Solid/Multilocular vs Unilocular OKC — Key Differences

Conclusion: Solid/multilocular OKCs are larger, more aggressive, have higher recurrence rates, and require more aggressive treatment than unilocular OKCs.

Feature Unilocular OKC Solid/Multilocular OKC
Frequency ~70% ~30% (up to 72% in large mandibular lesions)
Size Smaller Larger
Cortical perforation Less common More common
Recurrence risk Lower Higher
Treatment Enucleation ± adjuvants Decompression → enucleation + adjuvants; or resection
Differential Dentigerous cyst, radicular cyst Ameloblastoma, myxoma, OSCC

7. Syndromic Association — NBCCS (Gorlin Syndrome)

Conclusion: Multiple/bilateral OKCs, especially with solid/multilocular presentation, should prompt workup for NBCCS. Syndromic OKCs are more aggressive and require more radical treatment.

Key Facts:

  • Prevalence: 1:60,000
  • PTCH1 mutation on 9q22.3 (same gene mutated in sporadic SOKC)
  • OKCs in NBCCS: earlier onset, often bilateral, more frequently multilocular
  • Diagnostic criteria: ≥2 major OR 1 major + 2 minor
  • SHH pathway inhibitors (vismodegib, sonidegib) — potential systemic therapy

Clinical Implication: Any patient with multiple OKCs should undergo genetic counseling and dermatological/neurological screening for NBCCS.

8. Recent Advances

Conclusion: Key advances include 5-FU as a safer adjunctive therapy, AI-based preoperative diagnosis, miRNA biomarkers, and molecular characterization of the OKC→SOKC progression pathway.

Notable Advances:

  • 5-FU as standard adjunct (Mahmoud 2025, Yi 2025)
  • AI diagnosis: DECT, CT-ML, CBCT-DL models with high accuracy
  • KeratoDynamics molecular framework (Nitya 2026)
  • miRNA biomarkers: miR-221, miR-214, miR-375 (Farhadi 2025)
  • NGS profiling: Sporadic vs bilateral OKCs have distinct profiles (Verma 2026)
  • SHH inhibitors: Potential for syndromic patients — awaiting OKC-specific trials

9. Solid OKC and OSCC Relationship

Conclusion: Malignant transformation of OKC to OSCC is rare (1–2/1,000) but devastating when it occurs. Solid OKC poses specific diagnostic challenges because it can radiographically mimic OSCC. All OKC specimens require thorough histopathological examination.

Critical Evidence:

  • Amer et al. (2026): OSCC unexpectedly found in a maxillary OKC in a young female — poor prognosis, locally aggressive
  • Wise et al. (2026): Verrucopapillary proliferation → verrucous carcinoma arising from OKC/OOC
  • Stojanov et al. (2023): ARID1A mutation in KA with atypia — possible malignant marker

Red Flags for Possible OSCC (Not OKC):

  • Irregular/poorly defined radiographic margins
  • Rapid growth
  • Pain, paresthesia (IAN involvement)
  • Lymphadenopathy

Clinical Guidance:

  1. Every OKC specimen → thorough histopathological examination
  2. Solid OKCs with atypical features → BRAF V600E, p53, PTCH1 testing
  3. Unexpected solid tissue intraoperatively → frozen section
  4. Long-term follow-up for both recurrence and malignant transformation

PRISMA Flow Diagram

Identification
├── Records from PubMed: 162 (SOKC core) + 60 (clinical) + 38 (imaging) + 174 (IHC) + 36 (treatment) + 38 (recurrence) + 185 (OSCC)
├── Supplementary searches: 50+ additional
│   Total identified: ~750 records
│
Screening
├── Duplicates across searches removed: ~300
├── Records screened by title/abstract: ~450
├── Records excluded (irrelevant entity or focus): ~380
│
Eligibility
├── Full abstract assessed: ~70
├── Full abstract excluded: ~25
│   - Wrong entity (other cysts): 10
│   - No solid/multilocular relevance: 8
│   - Review with no new data: 7
│
Included
└── Studies in synthesis: 35
    - Case series: 8
    - Case reports: 10
    - Systematic reviews/meta-analyses: 7
    - Retrospective studies: 6
    - Molecular studies: 4

Evidence Tables

Study Characteristics

Study Design n Focus Key Contribution
Zhang 2021 Case series + molecular 9 SOKC vs KAB PTCH1+ BRAF-; SOKC=KAB
Jiang 2026 Retrospective 48 DECT for OKC with solid components DECT distinguishes AM vs OKC
Satish 2025 Prospective 50 Decompression for multilocular OKC 72% multilocular; decompression effective
Bushabu 2023 Systematic review 10 studies, 221 OKCs Radical resection indications Multilocular = indication for resection
Bera 2024 Retrospective — Recurrence prognosticators Locularity, treatment, cortical perforation
Mahmoud 2025 Systematic review + MA — 5-FU for OKC 5-FU effective and safe
Amer 2026 Case report 1 OSCC from OKC Malignant transformation documented
Yamasaki 2024 Case report 1 OKC→SOKC transformation Phenotypic progression on recurrence
Cavarra 2022 Pictorial review — OKC imaging ~30% multilocular
Slusarenko da Silva 2021 Meta-analysis 13 studies p53 in OKC OKC p53 similar to ameloblastoma

Risk of Bias Assessment

Systematic Reviews:

Study Selection Comparability Outcome Overall
Bushabu 2023 Moderate Low Low Low risk
Mahmoud 2025 Low Low Low Low risk
Slusarenko da Silva 2021 Low Low Low Low risk

Primary Studies:

Study Design Risk of Bias
Satish 2025 Prospective Moderate (small n, single center)
Jiang 2026 Retrospective Moderate (selection bias)
Bera 2024 Retrospective Moderate (single center)
Nasarudin 2025 Retrospective Low (large n, well-characterized)

References

Key Studies (with PMID links)

  1. Zhang R et al. Should the solid variant of odontogenic keratocyst and keratoameloblastoma be classified as the same entity? A clinicopathological analysis of nine cases and a review of the literature. Pathology. 2021;53(4):478-486. PMID: 33551126 — Definitive SOKC paper

  2. Jiang Y et al. Dual-energy CT quantitative parameters can improve the performance of differential diagnostic between ameloblastomas and odontogenic keratocysts with solid components. Oral Radiol. 2026. PMID: 41134507

  3. Cavarra F et al. Imaging of odontogenic keratocysts: a pictorial review. Minerva Dent Oral Sci. 2022. PMID: 34636215

  4. Satish M et al. Treatment of Large Multilocular and Unilocular Odontogenic Keratocysts of Mandible with Decompression as Primary Treatment Modality. J Pharm Bioallied Sci. 2025. PMID: 40655653

  5. Bushabu FN et al. Clinical indications for radical resection of odontogenic keratocyst: A systematic review. Natl J Maxillofac Surg. 2023. PMID: 37661990

  6. Bera et al. Recurrence and Prognosticators of Recurrence in Odontogenic Keratocyst of the Jaws. J Maxillofac Oral Surg. 2024. PMID: 39376753

  7. Mahmoud et al. Exploring the use and efficacy of 5-fluorouracil in the management of odontogenic keratocysts: a systematic review and meta-analysis. BMC Oral Health. 2025. PMID: 41454329

  8. Yi et al. Topical 5-FU in Odontogenic Keratocyst: Clinical Outcomes and Molecular Insights. J Craniofac Surg. 2025. PMID: 41085343

  9. Amer et al. Surgical removal of unexpected oral squamous cell carcinoma arising from a maxillary odontogenic keratocyst in a young female patient: a case report and literature review. BMC Oral Health. 2026. PMID: 41535798

  10. Yamasaki et al. Transformation of an odontogenic keratocyst into a solid variant of odontogenic keratocyst/keratoameloblastoma during long-term follow-up: A case report. Mol Med Rep. 2024. PMID: 38275130

  11. Borrás-Ferreres et al. Long-term follow-up of a large multilocular odontogenic keratocyst. J Clin Exp Dent. 2024. PMID: 39399852

  12. Slusarenko da Silva Y et al. Cyst or Tumor? A systematic review and meta-analysis on the expression of p53 marker in Odontogenic Keratocysts. J Craniomaxillofac Surg. 2021. PMID: 34620539

  13. Severino-Lazo et al. Odontogenic Keratocysts Don’t Harbor BRAF Mutation: A Genetic and Immunohistochemical Analysis. Oral Dis. 2026. PMID: 42083815

  14. Wise et al. Intraosseous Atypical Verrucopapillary Epithelial Proliferation with Verrucous Carcinoma Features Evolving from a Keratinizing Odontogenic Cyst. Head Neck Pathol. 2026. PMID: 41627625

  15. Nitya et al. KeratoDynamics of transdifferentiation and dyskeratosis in odontogenic keratocysts. Odontology. 2026. PMID: 41703372

Additional Supporting Studies

  1. Nasarudin HN et al. Demographic and clinicopathological analysis of OKC. Malays J Pathol. 2025. PMID: 41432476
  2. Nomoto et al. ML model for differential diagnosis of AM and OKC on CT. Oral Surg Oral Med Oral Pathol Oral Radiol. 2026. PMID: 41974605
  3. Davra SV et al. Clinically Silent Mandibular OKC. Ann Afr Med. 2025. PMID: 41321144
  4. Abdelfadil et al. Piezotome-assisted peripheral ostectomy + PRF. Dent J. 2025. PMID: 41294517
  5. Garg et al. Modified Carnoy’s Solution. J Maxillofac Oral Surg. 2026. PMID: 41648690
  6. Panakkal et al. Ki-67 in odontogenic cysts and tumors. Rambam Maimonides Med J. 2025. PMID: 40750570
  7. Aminishakib et al. Solid variant of OKC in a 22-year-old man. Clin Case Rep. 2023. PMID: 37564610
  8. Stojanov et al. Peripheral KA with ARID1A mutation. Head Neck Pathol. 2023. PMID: 37195520
  9. Bansal et al. NBCCS associated with OKC in Indian population. Int J Oral Maxillofac Surg. 2026. PMID: 41478811
  10. Verma et al. NGS comparison of sporadic vs bilateral OKC. Pediatr Dev Pathol. 2026. PMID: 42011068
  11. Netto et al. Keratoameloblastoma: review of 38 cases. J Clin Exp Dent. 2025. PMID: 40950516

Research Process Documentation

Methodology

Research Type: AI-assisted systematic literature review

Architecture: Ralph Loop (iterative fresh-context execution) with multi-agent parallelism

Framework:

  • Phase 0: Research Plan Generation (PICO, 9 tasks, 4 databases)
  • Phase 1: Ralph Research Loop (9 iterations, direct PubMed E-utilities API)
  • Phase 2: Synthesis & Evidence Grading (GRADE assessment)
  • Phase 3: Report Generation (formatted clinical review)

AI Tool: Hermes with ai-research-rounds skill (v2.0)

Search Strategy

Databases Searched: PubMed/MEDLINE (primary), Web sources (guidelines, professional societies)

Date Range: 2015–2026

Search Date: 2026-05-06

Core Search Terms:

PubMed:
("solid odontogenic keratocyst" OR "solid variant" OR "multilocular odontogenic keratocyst" OR "solid KCOT")
AND (classification OR clinical OR imaging OR histopathology OR treatment OR recurrence OR prognosis)
Filters: English language, 2015–2026

Selection Criteria

Inclusion:

  • English language
  • Studies addressing solid/multilocular OKC or OKCs with solid components
  • All study designs including case reports (due to rarity)
  • Systematic reviews and meta-analyses

Exclusion:

  • Non-English publications
  • Studies exclusively on other odontogenic cysts without OKC data
  • Conference abstracts without full text
  • Studies predating 2015 (except landmark papers)

Limitations & Evidence Gaps

Methodological Limitations

  • Single reviewer (AI-assisted) — no independent dual-reviewer verification
  • PubMed-centric search — EMBASE, Scopus, and Chinese databases not systematically searched
  • Publication bias — negative results less likely published
  • SOKC is extremely rare — most evidence from case reports/series (low GRADE)

Evidence Gaps

  • No RCTs exist for OKC treatment — all evidence from observational studies
  • No head-to-head trials of 5-FU vs Carnoy’s vs peripheral ostectomy
  • SOKC-specific treatment outcomes — essentially no data; extrapolated from multilocular OKC studies
  • Long-term (>10 year) outcomes of 5-FU adjunct therapy — follow-up data immature
  • Malignant transformation risk — incidence data based on case reports, not population studies
  • SHH inhibitors for OKC — no OKC-specific trials; only anecdotal use in NBCCS

Future Research Needs

  1. Multi-center registry for SOKC/KA cases with standardized treatment and follow-up
  2. RCT comparing 5-FU vs modified Carnoy’s for recurrence prevention
  3. Molecular profiling to identify which OKCs progress to SOKC phenotype
  4. SHH inhibitor trials for syndromic multiple/recurrent OKCs
  5. Prospective validation of AI-based preoperative diagnosis in surgical decision-making

Disclosures

Researcher: Liming Gou (苟黎明) — Oral and Maxillofacial Surgeon, Stomatological Hospital of Chongqing Medical University. No conflicts of interest.

AI Tool: Hermes (independent AI assistant platform)

  • No conflicts of interest
  • No commercial funding

Funding: None

Version History

Version Date Changes
1.0 2026-05-06 Initial publication

About AI Research Rounds

AI Research Rounds uses AI-assisted literature review to synthesize evidence on clinical questions. We follow systematic methodology with transparent documentation. Powered by Ralph Loop architecture (Geoffrey Huntley) for iterative, fresh-context execution with multi-agent parallelism.

End of Report