Management of peripheral giant cell granuloma around complete-arch fixed implant-supported prosthesis: A case series

Peripheral giant cell granuloma associated with dental implants: Case-series

PURPOSE

The objectives were to characterize clinico-pathologically a large series of peri-implant peripheral giant cell granuloma (PGCG), and investigate the role of foreign material as a possible etiological factor.

MATERIAL AND METHODS

The study was retrospective, conducted on peri-implant specimens submitted for histology between 2005 and 2021.

RESULTS

Three hundred and thirty-five peri-implant biopsies were retrieved, of which 52 (15.5%) were PGCG. The study population included 28 females and 24 males, age 35-92 years, mean 61. 51.2% reported bone involvement. The lesion involved the margins of the specimen in 65.3%, recurrence was reported in 46.1%. In 58.8% the implant was removed at the same time the specimen was submitted for histopathological analysis. Small foci of black granular foreign material were observed in 53.8% of cases of which 67.8% were birefringent under polarized light. The foreign material granules were not ingested inside multinucleated giant cells, but were scattered in the stromal compartment.

CONCLUSIONS

Peri-implant PGCG is locally aggressive, with frequent bone involvement and high recurrence rate, resulting in implant loss in the majority of cases. The high recurrence rate may be related to conservative or inadequate surgery. Foreign material although common does not seem to have a role in its development.

KRAS Mutation in an Implant-associated Peripheral Giant Cell Granuloma of the Jaw: Implications of Genetic Analysis of the Lesion for Treatment Concept and Surveillance

The aim of this case report was to detail diagnosis and therapy in a case of implant-associated peripheral giant cell granuloma (IA-PGCG) of the jaw. Case Report: The 41-year-old female attended the outpatient clinic for treatment of recurrent mandibular IA-PGCG. The lesion was excised and the defect was closed with a connective tissue graft of the palate. Healing of oral defects was uneventful, and no local recurrence has occurred during a follow-up of 7 months. Genetic examination of the lesion identified a somatic mutation in KRAS. Conclusion: The lesions are assessed as reactive-inflammatory changes in the mucous membrane of the oral cavity. The cause of the lesion is unknown. KRAS mutations are commonly found in various cancer tissues, but also in germline and mosaic RASopathies. Recently, KRAS mutations have been identified in several IA-PGCG. The clinical course of a frequently locally recurring lesion gives rise to the assumption that lesions of this type show characteristics known in benign neoplasms.

An analysis of the prevalence of peripheral giant cell granuloma and pyogenic granuloma in relation to a dental implant

Background

The aim of the present investigation was to evaluate the literature recurrence of peripheral giant cell granuloma and pyogenic granuloma associated with dental implants. It’s important to know the characteristics present in these lesions and possible effects on the prognosis of dental implants.

Methods

An electronic search without time restrictions was done in the databases: PubMed/Medline. With the keywords "Granuloma" OR "Granuloma, Giant Cell" OR "peripheral giant cell" OR "Granuloma, Pyogenic” AND "Dental implants" OR "Oral implants”.

Results

After applying the inclusion and exclusion criteria, a total of 20 articles were included, which reported 32 lesions (10 pyogenic granulomas, 21 peripheral giant cell granulomas and one peripheral giant cell granuloma combined with peripheral ossifying fibroma, all associated with implants). According to our review, these lesions are more frequent in males and in the posterior region of the mandible. Both excision and curettage of the lesion, compared to only excision, presented similar recurrences (40%). Explantation of the implant was performed in 41% of cases without additional recurrences. The results are not statistically significant when comparing one lesion to the other in terms of explantation (p = 0.97), recurrence (p = 0.57) or bone loss (p = 0.67).

Conclusions

The main therapeutic approach is tissue excision. The lesions show a high recurrence rate (34.4%), which often requires explantation of the associated implant. This recurrence rate is not affected by curettage after excision.

KRAS mutations in implant-associated peripheral giant cell granuloma

OBJECTIVES

To investigate the molecular pathogenesis of implant-associated peripheral giant cell granuloma (IA-PGCG).

METHODS

A convenience sample of 15 IA-PGCG cases was selected. Hotspot mutations of KRAS, FGFR1, and TRPV4 genes, previously reported in conventional giant cell lesions of the jaws, were investigated by Sanger sequencing. As these mutations could activate MAPK/ERK pathway, the expression of phospho-ERK1/2 was also evaluated by immunohistochemistry.

RESULTS

KRAS mutations were detected in 8/15 (53.4%) samples. Similar to conventional peripheral giant cell granuloma, the KRAS mutations most frequently occurred in codon 146 (p.A146V, n = 3), followed by codon 12 (p.G12A and p.G12D, n = 1 each) and codon 14 (p.V14L, n = 1). Variants of unknown significance (VUS) were also detected in two cases, affecting codons 37 (p.E37K) and 127 (p.T127I). All samples showed wild-type (WT) sequences for FGFR1 and TRPV4 genes. Consistent with MAPK/ERK pathway activation, all mononuclear cells of the lesion showed strong staining for phospho-ERK1/2 protein in the immunohistochemical analysis.

CONCLUSIONS

KRAS mutations and activation of the MAPK-ERK signaling pathway occur in IA-PGCG. This is the first study to demonstrate cancer-associated gene mutations in a non-neoplastic reactive condition associated with dental implants.