Faculty Bibliography

Laparoscopic approach was safely performed for the diagnosis and treatment of the submucosal tumors of the stomach because it is associated with low morbidity, mortality, and sound oncologic outcomes. However, no report on the long-term safety and efficacy of this surgery for large sized gastric GISTs has been published to date. We present a 63-year-old female case of a large gastric GIST of 19 cm removed by laparoscopic wedge resection.

Multiple osteochondromas (MO), previously known as hereditary multiple exostoses (HME), is an autosomal dominant disease characterized by the formation of several benign cartilage-capped bone growth defined osteochondromas or exostoses. Various clinical classifications have been proposed but a consensus has not been reached. The aim of this study was to validate (using a machine learning approach) an "easy to use" tool to characterize MO patients in three classes according to the number of bone segments affected, the presence of skeletal deformities and/or functional limitations. The proposed classification has been validated (with a highly satisfactory mean accuracy) by analyzing 150 different variables on 289 MO patients through a Switching Neural Network approach (a novel classification technique capable of deriving models described by intelligible rules in if-then form). This approach allowed us to identify ankle valgism, Madelung deformity and limitation of the hip extra-rotation as "tags" of the three clinical classes. In conclusion, the proposed classification provides an efficient system to characterize this rare disease and is able to define homogeneous cohorts of patients to investigate MO pathogenesis.

AIMS AND BACKGROUND/OBJECTIVE:Information is scarce on systemic treatment of pelvic osteosarcoma because most chemotherapy protocols for osteosarcoma include patients with extremity tumors and aged up to 30-40 years. METHODS:Data on patients <41 years of age with high-grade pelvic osteosarcoma were prospectively collected. Patients received two chemotherapy protocols consisting of methotrexate, cisplatin, doxorubicin (MAP) and standard-dose or high-dose ifosfamide. RESULTS:Forty patients between 11 and 36 years were included. The most frequent histological subtype was osteoblastic followed by chondroblastic (37.5%). Complete surgical remission was achieved in 65% of patients. Eighteen patients had MAP/standard-dose ifosfamide, 22 MAP/high-dose ifosfamide. Primary chemotherapy was given to 25 patients and 6 (24%) of them had a good histological response. Median follow-up was 32 months (range, 4-134). Five-year overall survival was 27.5%: 33% in localized and 0 in metastatic patients ( P = 0.02); 45% in patients with complete surgical remission and 0 for patients without complete surgical remission (P = 0.001). Local recurrence rate was 46%. In patients with complete surgical remission, 5-year overall survival was 32% with MAP/standard-dose ifosfamide and 59% with MAP/high-dose ifosfamide regimen (P = 0.3). CONCLUSIONS:Local control is the major issue in the treatment of pelvic osteosarcoma. Poor pathological response and high incidence of chondroblastic variant indicate different characteristics between pelvic and extremity osteosarcoma. Chemotherapy with MAP and high-dose ifosfamide might be beneficial in patients with pelvic osteosarcoma and warrants further investigation.

The complexity of pelvic anatomy and the extent of tumor growth makes treatment of patients with primary bone sarcomas in the pelvis difficult in terms of local control. Before the 1970s, most tumors in the bony pelvis were surgically treated with hindquarter amputation. Currently, improved techniques for clinical staging, adjuvant treatments, evolutions in metallurgy, and development of new surgical techniques make limb-salvage surgery and reconstruction possible alternatives to hemipelvectomy and resection-arthrodesis. The advantages of amputation over resections at the pelvis are a lower incidence of complications, a limited area at risk for recurrence, and a faster recovery time compared with all but the most limited pelvic resections. The disadvantages, especially after periacetabular resections, are leg-length discrepancy and impaired hip and gait function. The indication for limb salvage is the ability to obtain wide margins without compromising survival and function. Although having to resect the sciatic nerve to obtain adequate margins does not always mean that an amputation should be performed, the combination of a major pelvic resection and the functional consequences of sciatic nerve resection results in an extremity usually not worth saving; loss of femoral nerve function does not result in a significant gait disturbance, especially if the hemipelvis is stable. Reconstruction options after major pelvic resections have also evolved, but they remain difficult, especially when the acetabulum is involved.

BACKGROUND:Multiple hereditary exostoses is an autosomal dominant skeletal disorder characterized by wide variation in clinical phenotype. The aim of this study was to evaluate whether the severity of the disease is linked with a specific genetic background. METHODS:Five hundred and twenty-nine patients with multiple hereditary exostoses from two different European referral centers participated in the study. According to a new clinical classification based on the presence or absence of deformities and functional limitations, the phenotype of the patients was assessed as mild (the absence of both aspects), intermediate, or severe (the concurrent presence of both aspects). An identical molecular screening protocol with denaturing high-performance liquid chromatography and multiplex ligation-dependent probe amplification was performed in both institutions. RESULTS:In our cohort of patients, variables such as female sex (odds ratio = 1.840; 95% confidence interval, 1.223 to 2.766), fewer than five skeletal sites with exostoses (odds ratio = 7.588; 95% confidence interval, 3.479 to 16.553), EXT2 mutations (odds ratio = 2.652; 95% confidence interval, 1.665 to 4.223), and absence of EXT1/2 mutations (odds ratio = 1.975; 95% confidence interval, 1.051 to 3.713) described patients with a mild phenotype; in contrast, a severe phenotype was associated with male sex (odds ratio = 2.431; 95% confidence interval, 1.544 to 3.826), EXT1 mutations (odds ratio = 6.817; 95% confidence interval, 1.003 to 46.348), and more than twenty affected skeletal sites (odds ratio = 2.413; 95% confidence interval, 1.144 to 5.091). Malignant transformation was observed in 5% of patients, and no evidence of association between chondrosarcoma onset and EXT mutation, sex, severity of disease, or number of lesions was detected. CONCLUSIONS:The identified "protective" and "risk" factors, as well as the proposed classification system, represent helpful tools for clinical management and follow-up of patients with multiple hereditary exostoses; moreover, homogeneous cohorts of patients, useful for studies on the pathogenesis of multiple hereditary exostoses, have been identified.