Cancer-associated fibroblasts are an infrequent finding in the microenvironment of proliferative verrucous leukoplakia-associated squamous cell carcinoma.

BACKGROUND: Cancer-associated fibroblasts (CAFs) are generally associated with negative prognostic factors. This study compares the clinicopathologic impact of CAFs in oral squamous cell carcinoma in patients with a history of proliferative verrucous leukoplakia (p-scca) and patients with conventional squamous cell carcinoma of the buccal mucosa, gingiva, and palate (c-scca). METHODS: A retrospective clinicopathologic and immunohistochemical analysis of 97 tumor specimens from 78 patients (13 patients with proliferative verrucous leukoplakia-associated squamous cell carcinoma (n = 32) and conventional squamous cell carcinoma from the buccal mucosa, gingiva, and palate (n = 65) was conducted. Immunostaining with anti-alpha-smooth muscle actin (α-SMA) antibody was used to evaluate the presence of CAFs. RESULTS: α-SMA expression was an infrequent finding in p-scca and seen in only 6% of p-scca compared to 40% of c-scca (P < 0.0004). In the c-scca subgroup, α-SMA significantly correlated with tumor size (T) (P = 0.009), tumor thickness (P < 0.0009), perineural invasion (P = 0.009), and microscopic grade (P = 0.018). CONCLUSIONS: The presence of CAFs was an infrequent finding in our p-scca cohort which may contribute to its seemingly slower growing and less invasive growth pattern. In the cohort of c-scca patients, higher levels of CAFs correlated with microscopic invasiveness, tumor size, and perineural invasion. Practically, these are important observations as targeting strategies are being developed to combat carcinoma types where CAFs significance has been validated.

Central Dentinogenic Ghost Cell Tumor: An Update on a Rare Aggressive Odontogenic Tumor.

PURPOSE: Dentinogenic ghost cell tumor (DGCT) is a very rare odontogenic lesion, with most knowledge based on single case reports. Therefore, a comprehensive analysis was performed of the clinical and radiologic features of reported cases of DGCT with an emphasis on treatment modalities. MATERIAL AND METHODS: This is a case series of DGCTs collected from the literature after a systematic search of Medline's PubMed and Google Scholar. Three additional cases were included from the authors' files. Demographic data of the patients, lesion site and size, and radiologic features were analyzed. Treatment approach and events of recurrence were recorded. RESULTS: Forty-five cases (42 from the literature) were included. The mean age of patients was 39.7 ± 19.3 years (range, 12 to 79 yr) and the male-to-female ratio was 1.8:1. The mandible-to-maxilla ratio was 1.14:1, with the posterior region of the jaws being the most commonly involved site. Radiographically, 78% lesions were unilocular, 67% were mixed radiolucent and radiopaque, and 68% had well-defined borders. The mean lesion size was 4.0 cm (range, 1.8 to 13.0 cm). The primary treatment for 21 patients was conservative surgery consisting of enucleation or curettage. Follow-up information for longer than 1 year (mean, 6.2 ± 8.3 yr; range, 1 to 31 yr) was known for 15 patients, of whom 11 (73%) had recurrences. The primary treatment in 19 patients was radical surgery consisting of marginal or segmental resection. Follow-up information for longer than 1 year (mean, 3.3 ± 2.6 yr; range, 1 to 10 yr) was known for 12 patients, of whom 4 (33%) had recurrences. CONCLUSIONS: This study highlighted the potentially aggressive biological behavior of DGCTs that demands extensive surgery and long follow-up. However, owing to the rarity of DGCT, more well-documented cases with long follow-up periods are needed to further define the optimal treatment modalities and prognosis.