Oral Leiomyomatous Hamartoma of the Midline Maxillary Gingiva: A Case Report and Review of the Literature

Pornpop Rattana-arpha, Preuktichai Buriyameathakul, Puangwan Lapthanasupkul

Published Online: Aug 7, 2026 DOI DOI 10.12982/OSR.2026.047

Oral leiomyomatous hamartoma (OLH) is a rare lesion characterized by abnormal growth, with smooth muscle tissue as the predominant component. It mainly presents on the midline region of both the dorsal tongue and the maxillary alveolar ridge. This article reported a case of OLH in a 7-year-old Thai girl. The lesion presented as a pedunculated, normal-colored, soft tissue nodule located on the palatal gingiva at the midline between the maxillary deciduous central incisors. Panoramic radiograph showed no bony changes associated with the lesion. The clinical differential diagnoses included irritation fibroma, congenital epulis and non-angiomatous hamartoma. Complete excision was performed under local anesthesia. Microscopically, it revealed soft tissue mass surfaced by parakeratinized stratified squamous epithelium with mild acanthosis. Proliferative smooth-muscle fascicles were dispersed in the loose fibrous connective tissue stroma. The diagnosis of OLH was supported by positive immunohistochemical reactivity of smooth-muscle actin and desmin with no reactivity for S-100 protein. Postoperative wound healing was uneventful, and no recurrence was found during the 10 months follow-up period.

The focus on OLH in the anterior maxilla, epidemiological data, pathogenesis, clinical and histopathological features, and differential diagnosis are discussed herein.

anterior maxilla differential diagnosis midline midline maxillary gingiva oral leiomyomatous hamartoma

References

  1. Kobayashi A, Amagasa T, Okada N. Leiomyomatous hamartoma of the tongue: case report. J Oral Maxillofac Surg. 2001;59(3):337-40.
  2. Scarpelli AC, Coelho Novaes MJ, da Silva TA, Gomes CG, Novaes JB Jr, Mesquita RA. Oral leiomyomatous hamartoma: a case report and review of literature. Int J Pediatr Otorhinolaryngol Extra. 2007;2(3):198-201.
  3. Zaitoun H, Triantfyllou A. Smooth muscle hamartoma of the hard palate. J Oral Pathol Med. 2007;36(4):245-9.
  4. Stamm C, Tauber R. Hamartoma of tongue. Laryngoscope. 1945;55:140-6.
  5. Wushou A, Liu W, Bai XF, Xiong XP, Li G, Zhi KQ, et al. Clinical analysis of 194 cases of head and neck hamartoma. Oral Surg Oral Med Oral Pathol Oral Radiol. 2013;115(3):299-303.
  6. Iida S, Kishino M, Senoo H, Okura M, Morisaki I, Kogo M. Multiple leiomyomatous hamartoma in the oral cavity. J Oral Pathol Med. 2007;36(4):241-4.
  7. Alarcón-Sánchez MA, Nava-Villalba M, Escoto-Vasquez LS, Heboyan A. A systematic review of the clinicopathological characteristics of oral leiomyomatous hamartoma. World J Surg Oncol. 2024;22(1):326.
  8. Nava-Villalba M, Ocampo-Acosta F, Seamanduras Pacheco A, Aldape-Barrios BC. Leiomyomatous hamartoma: report of two cases and review of the literature. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2008;105(4):e39-45.
  9. Takahashi S, Koukita Y, Naruke J, Watanabe J, Suzuki A. Congenital epulis: a case report. Shikagakuho. 1962;62:55-9.
  10. Mushimoto K, Kakudo K, Ueno S, Uenaka H, Shirasu R, Takasu J. Leiomyomatous hamartoma of the gingiva: report of a case. Jpn J Oral Maxillofac Surg. 1982;28(4):493-6.
  11. Kajiyama M, Iino E, Kurokawa H, Fukuyama H, Ueno M. Leiomyomatous hamartoma in the region of upper medial alveolar gingiva: report of a case. Jpn J Oral Maxillofac Surg. 1983;29(8):1520-4.
  12. Kanekawa A. A case of hamartoma occurring in tongue and upper gingiva. Jpn J Oral Maxillofac Surg. 1990;36(2):317-20.
  13. Seki A, Maeno H, Tomizawa M, Suzuki M, Noda T. Congenital epulis, so-called leiomyomatous hamartoma: a case report. Jpn J Pediatr Dent. 1991;29(4):854-61.
  14. Ng KH, Siar CH, Latif HA. Leiomyoma of the incisive papilla region: a case report. Ann Dent. 1992;51(1):29-31.
  15. Semba I, Kitano M, Mimura T. Gingival leiomyomatous hamartoma: immunohistochemical and ultrastructural observations. J Oral Pathol Med. 1993;22(10):468-70.
  16. Takeda Y, Satoh M, Nakamura S, Matsumoto D. Congenital leiomyomatous epulis: a case report with immunohistochemical study. Pathol Int. 2000;50(12):999-1002.
  17. Corrêa L, Lotufo M, Martins MT, Sugaya N, de Sousa SC. Leiomyomatous hamartoma of the incisive papilla. J Clin Pediatr Dent. 2001;25(2):157-9.
  18. Kujan O, Clark S, Sloan P. Leiomyomatous hamartoma presenting as a congenital epulis. Br J Oral Maxillofac Surg. 2007;45(3):228-30.
  19. McGuff HS, Jones AC, Heim-Hall J, Keller TA. Case of the month. leiomyomatous hamartoma. Tex Dent J. 2009;126(6):544-5, 548-9.
  20. Zhang M, Matsuo K, Yamashita Y, Takahashi T. Leiomyomatous hamartoma of the midline maxillary gingival presenting as a congenital epulis: a case report with an immunohistochemical study. Int J Oral Maxillofac Surg. 2011;40(11):1322-6.
  21. ALQahtani D, Qannam A. Oral leiomyomatous hamartoma of the median maxillary gingiva: a case report and review of the literature. Int J Surg Pathol. 2013;21(4):413-6.
  22. Falci SGM, Mesquita ATM, Romañach MJ, de Almeida OP, dos Santos CRR. Oral leiomyomatous hamartoma associated with upper lip midline malformation: case report and review of the literature. Int J Pediatr Otorhinolaryngol Extra. 2013;8(1):e17-21.
  23. Damm DD. Nodule of incisive papilla. leiomyomatous hamartoma. Gen Dent. 2014;62(5):78-9.
  24. Raghunath V, Manjunatha BS, Al-Thobaiti Y. Gingival leiomyomatous hamartoma of the maxilla: a rare entity. BMJ Case Rep. 2016;2016:bcr2015213598. doi: 10.1136/bcr-2015-213598.
  25. da Silva DMF, Fernandes IA, Wu A, Neville BW. Oral leiomyomatous hamartoma of the anterior maxillary gingiva. Clin Adv Periodontics. 2016;6(4):190-4.
  26. Loomba A, Garg S, Dhindsa A, Kaur H, Jain N, Dhindsa P. Oral subcutaneous midline leiomyomatous hamartoma presenting as congenital incisive papilla overgrowth in a toddler. Contemp Clin Dent. 2017;8(1):148-50.
  27. Sanchez-Romero C, Bonan PRF, Pires FR, Silva-Junior GO, Azañero WD, de Almeida OP, et al. Leiomyomatous hamartomas of the oral cavity: clinicopathological and immunohistochemical features of 4 cases and literature review. Int J Surg Pathol. 2019;27(6):624-30.
  28. Yancoskie AE, Trochesset DA, Merer D, Fantasia JE, Kumar AM. Oral leiomyomatous hamartoma: presentation of 3 cases and review of the literature. Oral Surg Oral Med Oral Pathol Oral Radiol. 2024;137(1):e1-7.
  29. Pal SS, Khan SA, Navit S, Sah K, Agrawal A, Gaidhane H. Leiomyomatous hamartoma of incisive papilla with high frenal attachment: a case report. Int J Clin Pediatr Dent. 2024;17(6):717-22.
  30. Costello BJ, Rivera RD, Shand J, Mooney M. Growth and development considerations for craniomaxillofacial surgery. Oral Maxillofac Surg Clin North Am. 2012;24(3):377-96.
  31. Dhanuthai K, Banrai M, Limpanaputtajak S. A retrospective study of paediatric oral lesions from Thailand. Int J Paediatr Dent. 2007;17(4):248-53.
  32. Conrad R, Perez MC. Congenital granular cell epulis. Arch Pathol Lab Med. 2014;138(1):128-31.
  33. Patil S, Rao RS, Majumdar B. Hamartomas of the oral cavity. J Int Soc Prev Community Dent. 2015;5(5):347-53.
  34. Jordan RCK, Regezi JA. Oral spindle cell neoplasms: a review of 307 cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2003;95(6):717-24.
  35. Inaba H, Ohnishi Y, Inaba M, Niki H, Yamasaki Y, Morita S, et al. Clinicopathologic conference. painless mass of the cheek. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2003;95(1):3-6.
  36. Nguyen AP, Frydrych AM. Oral leiomyoma in an adult male: a case report. Open Dent J. 2017;11:520-6.
  37. Jones AC, Trochesset D, Freedman PD. Intraoral benign mesenchymoma: a report of 10 cases and review of the literature. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2003;95(1):67-76.
  38. Shamim T. The spindle cell neoplasms of the oral cavity. Iran J Pathol. 2015;10(3):175-84.

Rattana-arpha P, Buriyameathakul P, Lapthanasupkul P. Oral Leiomyomatous Hamartoma of the Midline Maxillary Gingiva: A Case Report and Review of the Literature: A case reports/series. Oral Sci Rep [Internet]. 2026 Aug 07 [cited 2026 Aug 08];47(3):440-447. Available from: https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=571

Rattana-arpha, P., Buriyameathakul, P. & Lapthanasupkul, P. (2026). Oral Leiomyomatous Hamartoma of the Midline Maxillary Gingiva: A Case Report and Review of the Literature. Oral Sci Rep, 47(3), 440-447. Retrieved from: https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=571

Rattana-arpha, P., Preuktichai Buriyameathakul and Puangwan Lapthanasupkul. 2026. "Oral Leiomyomatous Hamartoma of the Midline Maxillary Gingiva: A Case Report and Review of the Literature." Oral Sci Rep, 47(3), 440-447. https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=571

Rattana-arpha, P. et al. 2026. 'Oral Leiomyomatous Hamartoma of the Midline Maxillary Gingiva: A Case Report and Review of the Literature', Oral Sci Rep, 47(3), 440-447. Retrieved from https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=571

Rattana-arpha, P., Buriyameathakul, P. and Lapthanasupkul, P. "Oral Leiomyomatous Hamartoma of the Midline Maxillary Gingiva: A Case Report and Review of the Literature", Oral Sci Rep, vol.47, no. 3, pp. 440-447, Aug. 2026.

Pornpop Rattana-arpha, Preuktichai Buriyameathakul, Puangwan Lapthanasupkul "Oral Leiomyomatous Hamartoma of the Midline Maxillary Gingiva: A Case Report and Review of the Literature." Oral Sci Rep, vol.47, no. 3, Aug. 2026, pp. 440-447, https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=571