Miguel Caballero

Expression of membrane-bound mucins (MUC1 and MUC4) and secreted mucins (MUC2, MUC5AC, MUC5B, MUC6 and MUC7) in mucoepidermoid carcinomas of salivary glands.

Mucins are glycoproteins normally synthesized by a variety of secretory epithelial cells. The aim of this study was to investigate the expression of mucins (MUC1, MUC2, MUC4, MUC5AC, MUCB, MUC6, MUC7) in mucoepidermoid carcinomas, the most frequent malignant tumor of salivary glands. Forty mucoepidermoid carcinomas and twenty-two normal salivary glands were studied for these mucins by immunohistochemistry from formalin-fixed and paraffin-embedded material. Normal salivary glands frequently expressed MUC1 and MUC4, mainly in ductal cells; MUC5B and MUC7 stained mucous and serous acini respectively of submandibular and minor salivary glands; and MUC5AC and MUC2 were poorly detected in excretory ducts. All mucoepidermoid carcinomas expressed MUC1, and 38/40 tumors expressed MUC4. Both membrane-bound mucins stained membranes and cytoplasm of all cell types (epidermoid, intermediate, mucous, clear and columnar). MUC5AC and MUC5B stained glandular differentiated cells in most tumors (29/40 and 33/40 cases, respectively). MUC6 was positive in 13/40 tumors, and both MUC2 and MUC7 in only 2/40 tumors. The high expression of MUC1 was related to high histologic grades, high recurrence and metastasis rates and a shorter disease-free interval (P < 0.05). Conversely, MUC4 high expression was mainly related to low-grade tumors, lower recurrence rates and a longer disease-free interval (P < 0.05). In conclusion, mucoepidermoid carcinomas of salivary glands usually express MUC1, MUC4, MUC5AC and MUC5B; less frequently MUC6; and rarely MUC2 and MUC7. This mucin expression pattern can be useful for diagnostic purposes. Therefore, MUC1 expression is related to tumor progression and worse prognosis, whereas MUC4 expression is related to a better prognosis.

Adenosquamous carcinoma of the head and neck: criteria for diagnosis in a study of 12 cases

Aims:  Adenosquamous carcinoma (ASC) of the head and neck is an unusual neoplasm in which a general consensus with regard to diagnostic criteria has not yet been reached. In this study we report the clinicopathological results of 12 ASCs, with special attention to their histological and immunohistochemical characteristics in order to define this neoplasm more precisely.

Immunoarchitecture of lymphoid tissue in HIV-infection during antiretroviral therapy correlates with viral persistence

Plasma viral load and T-cell subset determinations in blood are the markers used for monitoring HIV-1 infection. However, key pathogenesis events, viral replication and most immunologic changes occur in the lymphoid tissues. We have studied the tonsillar biopsies of 30 patients in the early stages of the disease, before initiating treatment and after 12 and 36 months of fully effective highly active antiretroviral therapy. We have investigated the HIV RNA by polymerase chain reaction (lymphoid tissue viral load), the immunohistochemical HIV-p24 antigen expression, as well as the lymphoid tissue architecture and lymphoid cell subsets using morphometry. The lymphoid tissue viral load and the immunoexpression of p24, which was found to be mainly associated with follicular dendritic cells, decreased significantly after treatment, but did not disappear in all cases, even after 36 months of treatment. A significant improvement of the lymphoid tissue architecture was also observed after treatment, with recovery of follicular structures. These histological changes correlated with the lymphoid tissue viral load. Moreover, the counts of CD4+ increased whereas CD8+ and cytotoxic lymphocytes (CD8+granzyme B+) decreased significantly, the latter in both interfollicular and intrafollicular areas. However, these cellular counts after treatment did not reach those of lymphoid tissue of non-HIV-infected patients used as control cases. Naive (CD45RA+) and memory (CD45RO+) cells also improved significantly after treatment. In conclusion, in HIV-infection the impact of treatment can only be assessed completely in the lymphoid tissue reservoir, where most of the virus is stored and associated with follicular dendritic cells. Highly active antiretroviral therapy produces a significant recovery of lymphoid tissue architecture and lymphoid cell subsets, which are associated with the decrease of lymphoid tissue viral load. However, these parameters studied in lymphoid tissue are not re-established completely, even after 36 months of highly active antiretroviral therapy.

Weekly paclitaxel for platin-resistant stage IV head and neck cancer patients

Conclusions. Weekly paclitaxel may be an active and well tolerated chemotherapy regimen for patients with platin-resistant advanced head and neck cancer. Objectives. Weekly paclitaxel should be an active and well tolerated regimen for palliative treatment of platin-resistant patients with recurrent or metastatic carcinoma of the head and neck. We analyzed the antitumor activity and toxicity profile. Patients and methods. Sixty consecutive patients with advanced head and neck cancer were treated with 1 h infusion of paclitaxel, 80 mg/m2 weekly, for 6 consecutive weeks. Patients who showed disease response or disease stabilization continued until progression of disease. Results. A total of 719 doses of paclitaxel were administered to the 60 patients. No complete response was observed. Partial response and stable disease were observed in 26 (43.3%) and 9 (15%) patients, respectively. Median time to tumor progression for patients who responded to therapy was 6.2 months (SD=1.3; 95% CI, 3.7–8.6) and the overall median survival in this group of patients was 8.5 months (SD=1.4; 95% CI, 5.7–11.2). The main toxic effects were leukopenia (26.6%), anemia (43.3%), fatigue (37.4%), alopecia (18.7%), rash/desquamation (13.3%), and thrombophlebitis (6.8%).

OUTCOME OF TRANSORAL LASER MICROSURGERY FOR T2-T3 TUMORS GROWING IN THE LARYNGEAL ANTERIOR COMMISSURE

To evaluate the outcomes of transoral laser microsurgery (TLM) in the treatment of T2 to T3 laryngeal carcinomas growing in the laryngeal anterior commissure.

Factors associated with collagen deposition in lymphoid tissue in long-term treated HIV-infected patients.

Objective:The factors associated with fibrosis in lymphoid tissue in long-term treated HIV-infected patients and their correlation with immune reconstitution were assessed. Methods:Tonsillar biopsies were performed in seven antiretroviral-naive patients and 29 successfully treated patients (median time on treatment, 61 months). Twenty patients received protease inhibitors-sparing regimens and nine protease inhibitor-containing regimens. Five tonsillar resections of HIV-negative individuals were used as controls. Lymphoid tissue architecture, collagen deposition (fibrosis) and the mean interfollicular CD4+ cell count per μm2 were assessed. Results:Naive and long-term treated HIV-infected patients had a higher proportion of fibrosis than did HIV-uninfected persons (P < 0.001). Patients with greater collagen deposition showed lower levels of CD4+ cells in lymphoid tissue (P = 0.03) and smaller increase in peripheral CD4+ T cells (r = −0.40, P = 0.05). The factors independently associated with fibrosis in lymphoid tissue were age (P < 0.0001), treated patients with detectable lymphoid tissue viral load when compared with patients with undetectable lymphoid tissue viral load (median 5 vs. 12%, respectively, P = 0.017) and patients receiving a protease inhibitor-sparing vs. a protease inhibitor-containing regimen (median 8 vs. 2.5%, respectively, P = 0.04). Conclusion:Fibrosis in lymphoid tissue was associated with a poor reconstitution of CD4+ T cells and long-term antiretroviral therapy did not reverse this abnormality. HIV infection, older age, a detectable level of lymphoid tissue viral load in treated patients and protease inhibitor-sparing regimens seem to favour fibrosis in lymphoid tissue.

Meniscal repair using the FasT-Fix device in patients with chronic meniscal lesions

The aim of this prospective study was to evaluate meniscal suturing using the FasT-Fix device for chronic meniscal tears. This procedure was carried out on 25 patients between 2006 and 2007. Nineteen patients were male and the median age was 31 (14–47) years. The median waiting time to surgery was 27 (6–80) months and the median follow-up was 20 (14–29) months. Eleven patients (44%) required reconstruction of an associated anterior cruciate ligament (ACL) injury. 20 patients (80%) showed medial meniscus tears. All tears were located in the red zone or red–white zone. According to Barett’s criteria, meniscal tear healing was achieved in 21 patients (84%). Lysholm and Tegner scale scores improved from 60 (47–77) preoperatively to 95 (58–100) postoperatively and from 3 (2–6) preoperatively to 6 (3–9) postoperatively, respectively. There were no neurovascular complications. Revision surgery was necessary in one patient, in whom a partial meniscectomy was performed. The results obtained suggest that chronic meniscal tears in the zones described can be healed.

Lymphoid tissue viral burden and duration of viral suppression in plasma

Objectives To assess virological response in lymphoid tissue and its impact on the durability of response in plasma in HIV-1-infected persons who achieved sustained suppression of plasma viraemia with different antiretroviral regimens. Methods Consecutive patients on first-line antiretroviral therapy were included if they had a plasma HIV-1 RNA viraemia < 20 copies/ml within the last 6 months and tonsillar tissue accesible for biopsy. First-line therapy contained two nucleoside analogues: alone (2NRTI group, n = 3); plus a HIV-1 protease inhibitor (PI group, n = 11) or plus nevirapine (NVP group; n = 16). Patients were followed until virus was detectable in plasma, they changed therapy or were lost to follow-up. Results Tonsillar HIV-1 RNA could be detected (> 100 copies/mg) in 10 patients: one in the PI group (9%), six (38%) in the NVP group and in all three patients in the 2NRTI group. Primary resistance mutations could be detected in only 2 of these 10 patients. After a median of 9 months after the biopsies, viral suppression in plasma had failed in 6 of these 10 patients whereas failure had only occurred in 1 out of 20 with initially undetectable viral load in lymphoid tissue (P = 0.01; log rank test). Conclusions In patients with sustained viral suppression in plasma, triple therapy including a HIV-1 protease inhibitor was more potent than triple therapy containing nevirapine or dual therapy with nucleoside analogues to reduce viral burden in lymphoid tissue. A worse response in lymphoid tissue could not be explained by local selection of resistance and was associated with a less durable virological response in plasma.

Epiglottitis and necrotizing fasciitis: A life-threatening complication of infectious mononucleosis

Objective Life-threatening cervical complications associated with infectious mononucleosis are rare. The combination of acute epiglottitis and subsequent necrotizing fasciitis of the head and neck in a patient with infectious mononucleosis has not been reported to date. Material and methods A 47-year-old female with infectious mononucleosis and epiglottitis was admitted to hospital for i.v. therapy. Owing to her poor clinical condition and the spread of the infection to the throat and superior mediastinum, as evidenced by CT, a cervical debridement was performed. Results After cervical debridement, histological findings were consistent with necrotizing fasciitis. The bacteria identified were Streptococcus viridans, Veilonella spp. and Capnocytophaga spp. The patient was hospitalized for 33 days. Conclusions Mononucleosis, usually a benign condition, may be associated with life-threatening septic complications in the neck and chest. Serial CT or MRI scans are necessary to assess the development of the infection in the deep layers of the neck. Rapid medical treatment, extensive surgical debridement and intensive care are vital.

Gene single nucleotide polymorphism accumulation improves survival in advanced head and neck cancer patients treated with weekly paclitaxel.

Single nucleotide polymorphisms (SNPs) of certain genes involved in drug metabolism correlate with survival.