A 24-year-old woman, with reactive serology for HIV since 5 years ago, without antiretroviral treatment or clinical controls, who reported starting approximately one month ago with pain in the lower right maxillary region. He consulted a dentistry department where tumefaction was found in the right lower maxillary region, at the level of the third lower molar. Treatment with antibiotics and non-steroidal anti-inflammatory drugs was indicated. Two weeks later, she consulted again with no improvement in her symptoms, reporting increased pain and swelling. The symptoms were interpreted as a dental phlegmon and amoxicillin/clavulanic acid and corticosteroids were prescribed. One week before hospitalisation, and due to the increase in size of the described tumour, surgical drainage was performed, obtaining haematic material. Analgesics were prescribed and the same antibiotic regimen was maintained. Five days after this procedure she was admitted to our hospital.
As epidemiological antecedents, she reported addiction to inhalation cocaine, marijuana and smoking.
On admission she was lucid, afebrile, oriented in time and space; the physical examination revealed the existence of a tumour formation in the right lower maxillary region extending to the submental area, measuring approximately 10 × 10 cm, red-violet in colour, indurated, painful on pressure, which prevented the closure of the mouth, chewing, swallowing and speech. It involved the gum, including dental pieces, the peribuccal soft tissues and the right lower jaw. Homolateral submandibular adenomegaly was palpable, indurated, painless, adherent to skin and deep planes. The rest of the physical examination showed no alterations of clinical relevance. Chest X-ray was normal. The admission laboratory showed: Ht: 35%, WBC: 7. 200/mm3 (N: 70%, E: 0.3%, B: 1.6%, M: 5.6%, L: 21%); ESR: 21 mm 1 hour; TGO: 41U/l, TGP: 31 U/l, FAL: 153 U/l, glycaemia: 138 mg/dl, urea: 27 mg/dl, creatinine: 0.56 mg/dl, Na+: 136 mEq/l, K+: 4.1 mEq/l, prothrombin concentration 98%, KPTT: 30.6", pregnancy test: negative, VRDL: non-reactive. Serologies for Chagas and hepatitis B and C virus were negative and for toxoplasmosis: IgM: negative and IgG: positive 1/64. CD4+ T-cell count was 235 cells/ml (16.3%), CD8: 872/mm3 (60.5%) and HIV viral load was 154,263 copies/ml (log10 4.74).
An abdominal ultrasound revealed mild heterogeneous splenomegaly; the rest of the patient had no abnormalities. An excisional biopsy was performed for diagnostic purposes; histopathological examination of the material obtained showed a proliferation of atypical, medium to large lymphoid cells with regular nuclei, lax chromatin, presence of nucleoli attached to the cell membrane and amphophilic cytoplasm. Numerous mitoses and apoptosis phenomena were also observed. Immunohistochemistry revealed positivity for CD45, CD3, CD20, CD10 and Bcl-6 in the neoplastic cells, and negativity for CD138, MUM-1 and Bcl-2. The Ki67 cell proliferation index was 99%. Microbiological studies of the biopsy material were negative for BAAR, fungi and common germs. The definitive histopathological diagnosis was primary LB of the oral cavity. Bone marrow biopsy showed no infiltration by atypical lymphoid cells. Gram, Grocott and Ziehl Neelsen stains were negative.
The patient received 6 cycles of chemotherapy based on the EPOCH-R schedule (etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, with rituximab and intrathecal methotrexate). Episodes of neutropenia were treated with granulocyte colony-stimulating factor. After treatment, complete disappearance of the gum lesion was observed. Four years later, the patient is asymptomatic, with no evidence of neoplastic disease, undetectable viral load and CD4 362 cells/ml.
