Comparative analysis of the mast cell density in normal oral mucosa, actinic cheilitis and lip squamous cell carcinoma.

Previous studies have shown that the number of mast cells is increased in ultraviolet (UV) irradiated skin and in neoplasias. Actinic cheilitis (AC) is a lesion caused by excessive exposure to sunlight that can transform into lip squamous cell carcinoma. The aim of this study was to compare the number of mast cells in 4 groups: NOM = normal oral mucosa (n=6); MDAC = mild dysplasia in actinic cheilitis (n=13); SDAC = severe dysplasia in actinic cheilitis (n=13); and LSCC = lip squamous cell carcinoma (n=15). The sections were stained by histochemical technique of blue toluidine and visual counting was performed with the aid of a reticulum coupled to the microscope ocular. A calibrated observer performed the count in 5 fields by case at x400 magnification. The largest mean number of mast cells per group was observed in LSCC (40.1), followed by MDAC (30.5), SDAC (28.6) and NOM (12.2). There were significant differences between NOM and MDAC (p<0.05) and between NOM and LSCC (p<0.05). The increased density of mast cells observed in AC and in LSCC compared to NOM suggests a role for the mast cells in the development of these lesions.

Comparative analysis of the mast cell density in normal oral mucosa, actinic cheilitis and lip squamous cell carcinoma

Previous studies have shown that the number of mast cells is increased in ultraviolet (UV) irradiated skin and in neoplasias. Actinic cheilitis (AC) is a lesion caused by excessive exposure to sunlight that can transform into lip squamous cell carcinoma. The aim of this study was to compare the number of mast cells in 4 groups: NOM = normal oral mucosa (n=6); MDAC = mild dysplasia in actinic cheilitis (n=13); SDAC = severe dysplasia in actinic cheilitis (n=13); and LSCC = lip squamous cell carcinoma (n=15). The sections were stained by histochemical technique of blue toluidine and visual counting was performed with the aid of a reticulum coupled to the microscope ocular. A calibrated observer performed the count in 5 fields by case at ×400 magnification. The largest mean number of mast cells per group was observed in LSCC (40.1), followed by MDAC (30.5), SDAC (28.6) and NOM (12.2). There were significant differences between NOM and MDAC (p<0.05) and between NOM and LSCC (p<0.05). The increased density of mast cells observed in AC and in LSCC compared to NOM suggests a role for the mast cells in the development of these lesions.

Estudos prévios mostram que os mastócitos estão significantemente aumentados na pele irradiada por ultra-violeta e neoplasias. A queilite actínica (QA) é uma lesão causada por excessiva exposição solar, que pode transformar-se em carcinoma espinocelular de lábio. O objetivo deste estudo foi comparar o número de mastócitos em 4 grupos: MON = mucosa oral normal (n=6); QADL = queilite actínica com displasia leve (n=13); QADS = queilite actínica com displasia severa (n=13); e CECL = carcinoma espinocelular de lábio (n=15). Os cortes foram corados pela técnica histoquímica do azul de toluidina e a contagem visual foi realizada utilizando um retículo acoplado à ocular do microscópio. Um observador calibrado realizou a contagem em 5 campos por caso em magnificação de ×400. A média de mastócitos por grupo foi maior no CECL (40,1), seguida da QADL (30,5), QADS (28,6) e MON (12,2). Houve diferença estatisticamente significante entre MON e QADL (p<0,05) e entre MON e CECL (p<0,05). A maior densidade de mastócitos na QA e no CECL em relação à MON sugere um papel para os mastócitos no desenvolvimento dessas lesões.