Primary thymus tumors: retrospective case analysis at a reference center in Latin America, 2011-2019.

BACKGROUND: Thymic tumors are unusual neoplasms, representing 0.2 to 1.5% of tumors in humans, but correspond to 20% of mediastinal tumors and 50% of those that occur in the anterior mediastinum. They tend to appear around the fourth and fifth decades of life without gender predilection. Up to 30% of patients are asymptomatic, therefore many are incidentally diagnosed. Radical thymectomy is the treatment of choice with high survival rates when detected in the early stages. METHODS: This was a retrospective descriptive study, including 18 adult patients' diagnosis of thymic neoplasm, who were managed with surgical resection from 2011 to 2019. Information about demographics, clinical characteristics, imaging findings, surgical and medical management, plus histological findings was obtained and reported. RESULTS: 18 patients with thymic tumors were included, of which specific histologic studies reveled thymomas, carcinomas, neuroendocrine tumors, thymolipoma and thymic cyst. Mean age was 52.7 years, with a predominance of male population. The main symptom was dyspnea, followed by cough and chest pain. Paraneoplastic syndromes such as myasthenia gravis, aplastic anemia and Cushing syndrome were reported. 89% of cases were treated by radical thymectomy alone, while only 2 cases required chemotherapy and radiotherapy. There were no surgical complications. Mean hospital stay length was 11. 9 days, with only 1 mortality during hospital admission. 5-year survival rate was 81%. CONCLUSIONS: The treatment of choice is radical thymectomy, which has been shown to positively impact patient mortality. Early detection is key to improve patient outcomes.

Assessing the clinical value of microRNAs in formalin-fixed paraffin-embedded liposarcoma tissues: Overexpressed miR-155 is an indicator of poor prognosis.

Liposarcoma (LPS) is a malignancy with extreme heterogeneity and thus optimization towards personalizing patient prognosis and treatment is essential. Here, we evaluated miR-155, miR-21, miR-143, miR-145 and miR-451 that are implicated in LPS, as novel FFPE tissue biomarkers.A total of 83 FFPE tissue specimens from primary LPS and lipomas (LPM) were analyzed. A proteinase K incubation-Trizol treatment coupled protocol was used for RNA isolation. After polyadenylation of total RNA and reverse transcription, expression analysis of 9 candidate reference and 5 target miRNAs was performed by qPCR. Genorm and NormFinder were used for finding the most suitable molecules for normalization. Survival analyses were performed in order to evaluate the prognostic potential of miRNAs.MiR-103 and miR-191 are most suitable for normalization of miRNA expression in LPS. MiR-155 and miR-21 are clearly overexpressed (P<0.001) in LPS compared with LPM specimens, whereas miR-145 (P<0.001), miR-143 (P =0.008) and miR-451 (P=0.037) are underexpressed. MiR-155 (P=0.007) and miR-21 (P=0.029) are differentially expressed between well-differentiated, dedifferentiated, myxoid/round cell and pleomorphic LPs tumor subtypes. MiR-155 represents a novel independent indicator of unfavorable prognosis in LPS (HR = 2.97, 95% CI = 1.23-7.17, P = 0.016).

YKL-40 expression in soft-tissue sarcomas and atypical lipomatous tumors. An immunohistochemical study of 49 tumors.

BACKGROUND AND PURPOSE: YKL-40 is a glycoprotein that is expressed in many types of cancer cells. In some cancers, there is a correlation between high serum YKL-40 levels on the one hand and more aggressive disease and early death on the other. YKL-40 has never been studied in patients with soft-tissue sarcomas (STSs). We investigated whether YKL-40 is expressed in STS tissue and ascertained that the degree of expression is related to survival and/or the histological grade of the malignancy (FNCLCC). PATIENTS AND METHODS: We included archived tissue from 49 patients (40 with STS and 9 with atypical lipomatous tumor, 20 female and 29 male, mean age 58 (4-89) years) who were treated with tumor resection in 2004 or 2005 at the Department of Orthopedics, Rigshospitalet. The minimum length of follow-up with respect to survival was 5-7 years. Immunohistochemical analysis with anti-YKL-40 antibody using tissue microarray was performed on resected tumors, and a semiquantitative measure of the intensity of YKL-40 staining was performed. RESULTS: 41 of the 49 tumors were positive for YKL-40, and of these, 36 had moderate to intense staining. 24 of the patients died within the follow-up period, and the intensity of YKL-40 staining was significantly higher in tumors from patients who had died in the follow-up period than in tumors from those who survived (p = 0.01). The staining intensity was different for the 3 grades of malignancy (p = 0.004): it was higher in highly malignant tumors (FNCLCC grade 2 and grade 3) than in low-malignancy tumors (grade 1). INTERPRETATION: YKL-40 is expressed in soft-tissue sarcomas. There is a correlation between expression of YKL-40 in STS and both histological grade of the malignancy and survival. Whether or not YKL-40 expression is an independent prognostic variable could not be determined in the present study.

Surgical treatment of complex spinal cord lipomas.

PURPOSE: This paper shows the long-term benefits of total/near-total resection of complex spinal cord lipomas and meticulous reconstruction of the neural placode, and specifically, its advantage over partial resection, and over non-surgical treatment for the subset of children with asymptomatic virgin lipomas. METHODS: The technique of total resection and placode reconstruction, together with technical nuances, are described in detail. We added 77 patients with complex lipomas to our original lipoma series published in 2009 and 2010, to a total of 315 patients who had had total or near-total resection and followed for a span of 20 years. Long-term outcome is measured by overall progression-free survival (PFS) with the Kaplan-Meier analysis, and by subgroup Cox proportional recurrence hazard analysis for the influence on outcome of 4 predictor variables of lipoma type, presence of symptoms, prior surgery, and post-operative cord-sac ratio. These results are compared to an age-matched, lesion-matched series of 116 patients who underwent partial lipoma resection over 11 years. The results for total resection is also compared to two large published series of asymptomatic lipomas followed without surgery over 9 to 10 years, to determine whether prophylactic total resection confers better long-term protection over conservative treatment for children with asymptomatic lipomas.. RESULTS: The PFS after total resection for all lipoma types and clinical subgroups is 88.1 % over 20 years versus 34.6 % for partial resection at 10.5 years (p < 0.0001). Culling only the asymptomatic patients with virgin (previously unoperated) lipomas, the PFS for prophylactic total resection for this subgroup rose to 98.8 % over 20 years, versus 67 % at 9 years for one group of non-surgical treatment and 60 % at 10 years for another group of conservative treatment. Our own as well as other published results of partial resection also compare poorly to non-surgical treatment for the subset of asymptomatic virgin lipomas. Multivariate subgroup analyses show that cord-sac ratio is the only independent variable that predicts outcome, with a 96.9 % PFS for ratio < 30 % (loosest sac), 86.2 % for ratio between 30 and 50 %, and 78.3 % for ratio > 50 % (tightest sac), and a threefold increase in recurrence hazard for high ratios (p = 0.0009). Pre-operative patient profiling using multiple correspondence analysis shows the ideal patient for total resection is a child less than 2 years old with a virgin asymptomatic lipoma, who, with a PFS of 99.2 %, is virtually cured by total resection. CONCLUSION: Total/near-total resection of complex lipomas and complete reconstruction of the neural placode achieves far better long-term protection against symptomatic recurrence than partial resection for all lesions; and for the subset of asymptomatic virgin lipomas, also better than non-surgical treatment. Partial resection in many cases produces worse outcome than conservative treatment for asymptomatic lesions.

Asymptomatic lumbosacral lipomas--a natural history study.

BACKGROUND: Inevitable deterioration due to mechanical tethering is perceived as the natural history for complex congenital spinal lipomas of the conus medullaris region, even if asymptomatic at presentation. The conventional wisdom that prophylactic surgical untethering improves outcome has been challenged recently [1, 2]. This study examines the natural history of asymptomatic un-operated children with lumbosacral lipomas (LSL) and investigates whether predictive factors herald deterioration. METHODOLOGY: Over the past decade, children presenting with complex LSL to a single clinician at Great Ormond Street Hospital (GOSH), London, UK have undergone a thorough assessment focusing on neurological and urological evaluation and MRI of the lumbosacral spine. For children deemed to be asymptomatic, conservative management has been adopted with close periodic surveillance of neurological and urological function, thus avoiding untethering surgery unless symptomatic deterioration occurs. A retrospective review identified this cohort of children asymptomatic of their LSL and their progress closely recorded. DISCUSSION: This study suggests that the natural history of this subgroup of dysraphic patients may be more benign than hitherto considered. Conservative management with adoption of a novel surveillance policy and timely intervention only in the presence of symptomatic deterioration resulted in 71% of this series remaining clinically asymptomatic at mean follow up period of 5.9 years (range, 1.0-19.3 years). At 10 years, the cumulative risk of deterioration determined by the Kaplan-Meier method was 40%. Children aged<2 years, female, with presence of a transitional type of LSL and associated syrinx were independently associated with a higher risk of deterioration.

Malignant fat-forming solitary fibrous tumor (so-called "lipomatous hemangiopericytoma"): clinicopathologic analysis of 14 cases.

Fat-forming solitary fibrous tumor is a rare variant of solitary fibrous tumor (SFT). Generally regarded as benign, very few fat-forming SFTs with malignant histologic features have been reported. Here, we report 14 histologically malignant fat-forming SFTs to better characterize this subset. Seven patients were female and 7 were male, with ages ranging 20 to 93 years (median, 57 y). Five tumors were located in the lower limb, 3 in the trunk, 3 in abdominopelvic locations, 2 in the head and neck region, and 1 in the upper limb. The tumor size ranged from 3.4 to 20 cm (median, 8.6 cm). Histologically, all exhibited at least focal hypercellularity; 12 tumors had mitoses >4/10 high-power fields (range, 2 to 37; median, 8), 12 showed at least moderate atypia, and 8 showed necrosis. It should be noted that 7 tumors contained only mature adipose tissue, whereas 5 contained multivacuolated lipoblasts and 2 had areas resembling atypical lipomatous tumor (ALT). Immunohistochemically, CD34 and CD99 were positive in most cases (11 of 14 and 8 of 10, respectively); MDM2 and CDK4 were both negative in all 4 cases tested (including both tumors with ALT-like areas). Follow-up data from 10 cases (median duration, 47.5 mo; range, 5 to 76) showed 2 patients with multiple metastases (both to lung and bones, and 1 each to breast and to soft tissue), both of whom died of disease. In conclusion, fat-forming SFTs exhibiting malignant histologic features have potential for aggressive behavior. The presence of lipoblasts and/or ALT-like areas, although described in some "benign" examples of fat-forming SFT, seems much more common in the malignant subset and may prompt a careful search for morphologic evidence of malignancy in any case of fat-forming SFT.

Molecular testing for lipomatous tumors: critical analysis and test recommendations based on the analysis of 405 extremity-based tumors.

Ancillary molecular testing has been advocated for diagnostic accuracy in the differentiation of lipomas from atypical lipomatous tumors/well-differentiated liposarcomas (ALT/WDL); however, the implications and specific indications for use are not well-established in the current literature. Herein, we extend previous findings by quantitatively evaluating the impact of molecular testing of lipomatous neoplasms in our routine clinical practice, how it modifies the historical perspective of their clinical course, and the effect of distinct surgical procedures in modulating the risk of local recurrence for these tumors after molecular classification. On the basis of these analyses, we suggest a specific set of basic recommendations for complementary molecular assessment in the diagnosis of lipomatous tumors. Four hundred and five lipomatous neoplasms located in the trunk and extremities were analyzed histologically and for the presence of 12q13-15 amplification on paraffin-embedded tissues by assessing MDM2/CPM amplification. Survival analyses were calculated with Kaplan-Meier and compared with the log-rank. Multivariate analysis was evaluated by the Cox regression method. The 405 tumors were histologically classified as ordinary lipoma (n=324), intramuscular lipoma (n=29), and ALT/WDL (n=52). The level of agreement between the histologic diagnosis and the molecular diagnosis was high (96%) but pathologists showed a tendency to overestimate cytologic atypia and the diagnosis of ALT/WDL (precision, 79%; accuracy, 88%). Molecular assessment led to a major diagnostic reclassification in 18 tumors (4%). Eleven of the tumors histologically classified as ALT/WDL were reclassified as ordinary lipoma (n=5) and intramuscular lipoma (n=6); none of which recurred. Seven ordinary lipomas were reclassified as ALT/WDL, 6 of which were larger than 15 cm and deeply located; 2 recurred locally. After molecular data, the 5-year local recurrence rates for ordinary lipoma, intramuscular lipoma, and ALT/WDL were 1%, 12%, and 44%, respectively. Multivariate analyses after molecular assessment showed tumor type and type of resection to be associated with the risk of local recurrence. Complementary molecular testing refines the histologic classification of lipomatous tumors and better estimates the impact of surgical procedures on the risk of local recurrence. Pathologists tend to overestimate the degree of cytologic atypia and the indiscriminate use of molecular testing should be avoided, especially for extremity-based tumors. Molecular testing should be considered for "relapsing lipomas," tumors with questionable cytologic atypia (even if widely excised), or for large lipomatous tumors (>15 cm) without diagnostic cytologic atypia.

Long-term outcome of total and near-total resection of spinal cord lipomas and radical reconstruction of the neural placode, part II: outcome analysis and preoperative profiling.

OBJECTIVE: To show the long-term benefits of total and near-total resection of complex spinal cord lipomas and reconstruction of the neural placode. METHODS: We analyzed 238 patients with dorsal, transitional, and chaotic lipomas who had total resection as described in part I for overall progression-free survival probability (PFS, Kaplan-Meier analysis) over 16 years. We also analyzed subgroup proportional recurrence hazard (Cox analysis) of 6 outcome predictors of sex, lipoma type, age, preoperative symptoms, previous surgery, and postoperative cord-sac ratio. These results were compared with an age-matched, lesion-matched series of 116 patients followed for 11 years after partial lipoma resection and with the Parisian series of nonsurgical treatment. RESULTS: The immediate effects of surgery were similar between total and partial resection: both achieved greater than 95% symptom stabilization or improvement rate. The neuro-urologic complication rates for the groups were also similar, 4.2% and 5.2% for total and partial resection, respectively. The combined cerebrospinal fluid leakage and wound complication rate of total resection was much lower at 2.5% than the 6.9% for partial resection, but both were better than published rates. The overall PFS for total resection was 82.8% at 16 years, comparing much more favorably with 34.6% for partial resection at 10.5 years (P < .0001). Culling only the asymptomatic patients with virgin (previously unoperated) lipomas to match the patient profile of the Parisian series, the PFS for prophylactic total resection for this subgroup increased to 98.4% at 16 years, versus 67% at 9 years for no surgery and 43.3% at 10.5 years for our own partial resection series, with a remarkable statistical difference between total and partial resection (P = .00001). Subgroup analyses showed that sex and lipoma type did not affect outcome. For the other predictor variables, while univariate analyses showed that young age, absence of symptom, and virgin lipomas correlated with better statistical PFS than older age, symptoms, and redo lipomas, these effects vanished with multivariate analyses. Cord-sac ratio stood alone as the only influential outcome predictor in multivariate analysis, with a 96.6% PFS for a low ratio of <30% and an 80.6% progression-free probability for a high ratio of >50%, and a 3-fold increase in recurrence hazard for high ratios (P = .0009). This suggested that all the individual effects of the other predictor variables could be reduced to whether a low cord-sac ratio could be achieved with total lipoma resection and placode reconstruction. Cord-sac ratio was the obvious factor that differentiated the outcomes between total and partial resection, the latter associated with a >90% chance of having a high cord-sac ratio. CONCLUSION: Total and near-total resection of lipomas and complete reconstruction of the neural placode produced a much better long-term progression-free probability than partial resection and nonsurgical treatment. The perioperative complications for total resection were low and compared favorably with published results. A low postoperative cord-sac ratio and well-executed placode neurulation were strongly correlated with good outcome. The ideal preoperative patient profile with early disease stabilization and the best recurrence-free probability is an asymptomatic child less than 2 years without previous lipoma surgery. There are strong indications that partial resection in many cases produces worse scarring on the neural placode and worse prognosis than no surgery.

Survival after resection of primary cardiac tumors: a 48-year experience.

BACKGROUND: Primary cardiac tumors are rare but have the potential to cause significant morbidity if not treated in an appropriate and timely manner. To date, however, there have been no studies examining survival characteristics of patients who undergo surgical resection. METHODS AND RESULTS: From 1957 to 2006, 323 consecutive patients underwent surgical resection of primary cardiac tumors; 163 (50%) with myxomas, 83 (26%) with papillary fibroelastomas, 18 (6%) with fibromas, 12 (4%) with lipomas, 28 (9%) with other benign primary cardiac tumors, and 19 (6%) with primary malignant tumors. Operative (30 day) mortality was 2% (n=6). Univariate analysis indicated that patients who underwent resection of fibromas and myxomas had superior survival characteristics in comparison to the remainder of tumor variants; these results were consistent after adjusting for age at surgery, year of surgery, and cardiovascular risk factors. Based on actuarial characteristics of the 2002 U.S. population, patients who underwent myxoma resection had survival characteristics that were not significantly different from that of an age and gender matched population (SMR 1.11, P=0.57) whereas those who underwent resection of fibromas (SMR 11.17, P=0.002), papillary fibroelastomas (SMR 3.17, P=0.0003), lipomas (SMR 5.0, P=0.0003), other benign tumors (SMR 4.63, P=0.003), and malignant tumors (SMR 101, P<0.0001) had significantly poorer survival characteristics. Furthermore, malignant tumors in younger patients were highly fatal (HR 0.899, P<0.0001). Although the most significant predictor of mortality was tumor histology, survival was also influenced the by the duration of CPB and NYHA III/IV; the impact of these risk factors varied with time. The cumulative incidence of myxoma recurrence was 13% and occurred in a younger population (42 versus 57 years, P=0.003) with the risk of recurrence decreased after 4 years. CONCLUSIONS: Surgical resection of primary cardiac tumors is associated with excellent long-term survival; patients with cardiac myxomas have survival characteristics that are not significantly different from that of a general population. Predictors of mortality are primarily related to tumor histology but also include clinical characteristics such as symptomatology and duration of CPB.

Survey of neoplasia in red kangaroos (Macropus rufus), 1992-2002, in a zoological collection.

An increase in the proportion of cases with neoplasia observed in a collection of captive red kangaroos (Macropus rufus) when compared with historical records and the paucity of reported neoplasms in kangaroos in the literature prompted a 10-yr review of all red kangaroo necropsies. Individual necropsy, medical, and inventory records for all kangaroos at the Kansas City Zoo were reviewed for the period 1 January 1992 to 31 December 2002. Two squamous cell carcinomas of the oral cavity, two mammary gland adenocarcinomas, a multicentric T-cell lymphosarcoma, and one submucosal pyloric lipoma were diagnosed in six of 28 kangaroo deaths. Three neoplasms were diagnosed antemortem. Four of the six neoplasms were considered malignant, and all four had metastasized. The mean age at death was 11 yr. All six animals with neoplasms were female; however, the exhibit population was composed solely of females. Only 11 cases of neoplasia in red kangaroos have been reported in the literature. On the basis of these cases and a review of the literature, the most commonly observed neoplasms in red kangaroos are mammary gland adenocarcinomas and oral squamous cell carcinomas. Common denominators were not identified in these cases, although chronic gingivitis could have been a contributing factor in the development of the oral squamous cell carcinomas.

Prevalence and risk factors associated with outcome of surgical removal of pedunculated lipomas in horses: 102 cases (1987-2002).

OBJECTIVE: To determine the prevalence of pedunculated lipomas and identify risk factors affecting postoperative complications and survival in horses at a veterinary teaching hospital undergoing surgery for colic caused by pedunculated lipomas. DESIGN: Retrospective study. ANIMALS: 102 horses with a diagnosis of pedunculated lipoma. PROCEDURE: Age, breed, weight, and sex of horses with pedunculated lipomas were compared with the total equine hospital population and the population of horses admitted for abdominal surgery during the same period. Follow-up information was obtained by reevaluation or contact with owners via telephone or written request. RESULTS: Prevalence of pedunculated lipomas as a reason for abdominal surgery in horses, compared with the population of horses with and without lipomas admitted for abdominal surgery, was 10%. Castrated male Saddlebred and Arabian horses > 14 years old were identified as being at risk for developing pedunculated lipomas. Postoperative complications were detected in 72% of horses with pedunculated lipomas. Variables associated with low survival rates included surgery before 1992, heart rate > 80 beats/min, abnormal color of abdominal fluid, pale mucous membranes, surgery requiring intestinal resection, and inability to attain a mean arterial pressure > or = 100 mm Hg. Horses undergoing surgery from 1992 to 1996, weighing < 409 kg (900 lb), or requiring jejunojejunal anastomosis had a high survival rate. CONCLUSIONS AND CLINICAL RELEVANCE: Although many of the variables reflected the health of the horse at the time of surgery, results may help veterinarians recognize risk factors associated with development of pedunculated lipomas and better predict the outcome of horses undergoing surgery for colic caused by pedunculated lipomas.

Male breast disorders in Jordan. Disease patterns and management problems.

OBJECTIVE: To highlight the features and management problems of male breast disorders in an eastern country such as Jordan. METHODS: Data regarding 33 male patients who underwent surgery for breast diseases in the Department of Surgery at Jordan University of Science and Technology, Irbid, Jordan, between the year 1996 and 2002 were analyzed. RESULTS: Gynecomastia (45.5%), ductal carcinoma (18.2%), and lipoma (12.1%) were the most frequent lesions. Endocrine testing when the clinical diagnosis was physiologic gynecomastia was not yielding. Many features of male breast carcinoma in Jordan (symptomatology, male to female ratio, high education rate, age, diagnostic yield of fine-needle aspiration, histological type, and estrogen receptor status) did not depart from the experience of others. Delayed presentation is evident from the fact that 57% of tumors were stage III. Loco-regional control was achieved by modified radical mastectomy. Tamoxifen was used in 5 patients, and chemotherapy in 4 patients. The patient with stage I is still disease free 6 years after the diagnosis. The 5-year survival rate for stages II and III was zero. Rare lesions (cystic hygroma, cystic mastopathy, fibroadenoma, duct papilloma, tuberculosis, periductal mastitis, and the previously unreported primary primitive neuroectodermal tumor of the breast) accounted for the rest of the group. The patient with primary primitive neuroectodermal tumor of right breast was treated by mastectomy and adjuvant chemotherapy. He remains disease free 31 months after the diagnosis. CONCLUSION: Unawareness and the fact that male breast enlargement is considered a social stigmata are responsible for the delayed presentation. The value of fine needle aspiration cytology and mammography is not widely appreciated. The wide spectrum of potential pathologies calls for referring all patients to specialized breast units.

[Differential diagnosis and surgical treatment of colorectal nonepithelial tumors]. / Differentsial'naia diagnostika i khirurgicheskoe lechenie pri kolorektal'nykh neépitelial'nykh opukholiakh.

An analysis of results of the examination and treatment of 92 patients with nonepithelial colorectal tumors has shown that the correct diagnosis can be made in 82% of the cases on the basis of using complex X-ray, ultrasonic and endoscopic methods. Of decisive significance in determination of the tumor tissue character is the morphological investigation. Extensive surgical interventions were performed due to suspected malignization on 21 patients with benign nonepithelial tumors. In other cases (n = 49) the organ-saving operations were fulfilled. The decision between the volumes of the surgery for malignant nonepithelial tumors (n = 24) was not difficult in most cases and depended on the spread of the oncological process. The 5-year survival in this group of patients was 57%. No recurrences were noted after ablation of benign tumors.

Resección de tumores retroperitoneales / Retroperitoneal tumors resection

Antecedentes: Los Tumores Retroperitoneales (TRP), constituyen entidades de escasa observación, frecuentemente malignas y, generalmente, de diagnóstico tardío. Su exéresis completa obliga, asiduamente, a resecar órganos vecinos. Objetivo: Analizar las resecciones de TRP realizadas personalmente durante 5 años (1992 a 1996). Lugar de Aplicación: Hospital Angel C. Padilla y práctica privada. Diseño: Estudio retrospectivo. Material y Métodos: se analizan 9 resecciones de TRP en ocho pacientes, cuatro de ellos mujeres. Tres de los diagnósticos fueron intraoperatorios, en tumores benignos; los restantes, clínico, ecográfico y tomográfico. Resultados: No hubo mortalidad peri-operatoria. Las resecciones de lesiones benignas fueron completas. 5 de 8 pacientes presentaban Sarcomas; 4 requirieron resección de órganos vecinos, incluyendo colon izquierdo, bazo y riñón derecho. 3 de 5 Sarcomas fueron Liposarcomas. Ninguno fue considerado irresecable. Conclusiones: Se han resecado ocho TRP primitivos y uno recidivado. Hallazgo intraoperatorio: dos casos. Los restantes se diagnosticaron con Ecografía y TAC. Los Sarcomas representaron 5 de 8 pacientes; de ellos, 3 fueron Liposarcomas. Los dos restantes fueron Condrosarcoma y Fibrohistiocitoma maligno. Un Liposarcoma fue reoperado antes de los 8 meses por recidiva; pero globalmente haan mostrado mejor respuesta al tratamiento. Los dos fallecidos por sus tumores fueron portadores de las otras formas histológicas. La resección de vísceras vecinas fue necesaria en 4 de 5 Sarcomas, no siempre relacionadas con el volumen. Se resecaron colon izquierdo, bazo y riñón derecho. (AU)

Results of irradiation of infiltrative lipoma in 13 dogs.

Thirteen dogs with infiltrative lipomas were treated with cobalt 60 radiation. Four of the thirteen dogs also received either whole body (n = 2) or combination local/whole body (n = 2) hyperthermia in conjunction with radiation therapy. Cytoreductive surgery was performed prior to radiation in 10 dogs, although only 3 dogs had microscopic disease at the time of radiation therapy. Dogs received a total dose of 45.6 Gy-63 Gy in 2.5-4 Gy/fraction on either a Monday/Wednesday/Friday schedule or on a daily Monday through Friday schedule. Twelve of the 13 dogs had computed tomography (CT) images acquired prior to irradiation. Survival time was determined from the time of completion of radiation therapy. Survival ranged from 6 months to 94 months, with a median (95% confidence interval) of 40 (18.5-77) months and a mean of 46.4 months. Only one dog was euthanized due to persistent signs related to the infiltrative lipoma at 6 months after the end of radiation therapy. There was no apparent difference in response based on whether or not the dogs received hyperthermia in conjunction with irradiation, although the numbers were too small to make any significant conclusions. It appears that dogs with infiltrative lipomas can benefit from external beam irradiation alone or in combination with surgery to effect long-term local tumor control.

Survival of patients with HTLV-I-associated lymph node lesions.

Adult T-cell leukaemia/lymphoma (ATLL), is a malignant condition associated with human T-cell leukaemia virus type I (HTLV-I). Usually, although not uniformly, histopathological examination of the lymph nodes shows a pleomorphic type. In addition, some patients with pre-overt ATLL show a Hodgkin's disease-like morphology and lymph nodes in non-neoplastic carriers show features of lymphadenitis. To characterize further the clinicopathological features of HTLV-I-associated lymphadenopathy, the histopathological features of the lymph nodes of 289 patients were classified into five types: lymphadenitis ( n=14), Hodgkin's-like (Hodgkin's) ( n=18), pleomorphic (medium and large cells) ( n=219), pleomorphic small cell ( n=11), and anaplastic large cell (ALC) ( n=27). Survival data were analysed according to the histopathological features of the lymph nodes. The pleomorphic type, which showed typical features of ATLL, was associated with a highly aggressive course and an initially high mortality, followed by a rapid decrease in survival. This pattern was also observed in patients with the ALC type. All cases with lymphadenitis were still alive at the end of the study, while survival progressively decreased in the Hodgkin's type. The small cell type showed an initial rapid decrease in survival followed by a plateau. These results show that the survival trends of patients with pleomorphic and anaplastic lymph node lesions are similar to those with ATL lymphoma, while patients with the lymphadenitis type of lesion were considered to have a non-neoplatic status. There is at present no effective therapy for ATLL, but in the future, these classification and survival data might be useful for the selection of appropriate chemotherapeutic regimens for patients with ATLL.

Nonlymphoid vertebral canal tumors in cats: 11 cases (1987-1995).

OBJECTIVE: To determine outcome of cats with nonlymphoid tumors of the vertebral canal that undergo surgery. DESIGN: Retrospective study. ANIMALS: 11 cats. PROCEDURE: Information obtained from the medical records included signalment, tumor location, gross evaluation of completeness of surgical excision, histologic diagnosis, and survival time. RESULTS: Median age of cats was 12 years: all cats had negative FeLV and feline immunodeficiency virus test results. All cats underwent a hemilaminectomy or dorsal laminectomy. The tumor was located in the thoracic portion of the vertebral column in 6 cats. Six cats had intradural-extramedullary tumors. Tumors included meningioma (n = 5), malignant nerve sheath tumors (2), and meningeal sarcoma, chondrosarcoma, lipoma, and osteosarcoma (1 each). One cat was lost to follow-up, 1 cat with meningioma was alive 1,400 days after surgery, and 1 cat with a nerve sheath tumor was alive 2,190 days after surgery. Median survival time for the other 4 cats with meningioma was 180 days (range, 30 to 600 days). CLINICAL IMPLICATIONS: Cats with nonlymphoid vertebral canal tumors that undergo surgery may have a good prognosis.

Infiltrative lipoma in dogs: 16 cases (1981-1992).

Medical records of 15 dogs with infiltrative lipoma, 1 of which had 2 lesions, were reviewed. Median age of affected dogs was 6.0 years, and median weight was 30.5 kg. The ratio of females to males was 4:1. Eight of the dogs were Labrador Retrievers. In 8 dogs, the lesions had previously been excised. There was not any apparent site predilection. Excision was the only treatment in all 15 dogs, and follow-up information was available for all dogs. Two dogs, each of which had 1 tumor, were euthanatized immediately after surgery, because the tumor could not be completely excised. Of the remaining 14 tumors, 5 (36%) recurred. Median time to recurrence for these 5 tumors was 239 days (range, 96 to 487 days). By means of Kaplan-Meier analysis, the percentage of dogs disease free 1 year after surgery was calculated to be 67%.

An analysis of 75 cases of intestinal obstruction caused by pedunculated lipomas.

A retrospective study of 75 cases of pedunculated lipoma obstruction (PLO) of the intestine was conducted. Age, breed and sex distributions were compared to the non-PLO colic population. Horses in the PLO group were significantly older than in the non-PLO colic group (P < 0.001). A significant increase in risk of PLO was associated with geldings (O.R. 2.32) and with ponies (O.R. 3.75). Of the 75 PLO cases analysed, 69 were strangulating, 70 involved small intestine and 5 involved small colon. Cases of strangulation obstruction tended to have lipomas originating distant to the mesenteric border of the intestine. The short-term survival rate for PLO cases was 48%. Long-term survival rate was 38%. Lipoma weight of some of the PLO group was compared with that from an asymptomatic pedunculated lipoma (APL) group. The two weight distributions were significantly different (P < 0.001).

The clinical importance of DNA synthesis and aneuploidy in bone and soft tissue tumours.

DNA flow cytometric analysis including the analysis of S-phase fraction was performed on 46 bone and soft tissue tumours. Histologically, 24 lesions were benign, 11 were low grade and 11 were high grade malignant tumours. The percentages of aneuploidy in these groups were 29, 54 and 82, respectively. The S-phase fraction was smaller than 14% in all benign tumours. High S-phase fraction (> or = 14%) was found in 3 out of 11 low-grade tumours (27%) and in 9 out 11 high-grade tumours (82%). Seven of nine patients who died of metastatic disease during the average 5 year follow-up had aneuploid stemlines with S-phase fraction higher than 14%. Histologically, these were all high-grade tumours. Three patients with high S-phase in low-grade tumours survived. We conclude that high DNA synthetic activity in an aneuploid population, more than the DNA aneuploidy alone, has prognostic significance in musculoskeletal tumours.