Metastatic cervical carcinoma to the breast.

Metastatic disease to the breast is often an unexpected diagnosis in a female who presents with a breast mass. The most important factor suggesting the appropriate diagnosis is a history of cancer. Correlation of mammographic and ultrasonographic findings may also raise the possibility of a metastatic mass. A well-defined, noncalcified dense mass on film-screen mammography, which also shows low-level homogeneous echoes without posterior acoustic enhancement, suggests the diagnosis. It is important that the diagnosis be made by fine needle aspiration or excisional biopsy so as to expedite appropriate therapy.     

MR imaging of colonic lipoma

Colonic lipomas may present with symptoms similar to colonic malignancies but require a much less aggressive surgical approach to control the symptoms and provide a cure. This case illustrates the efficacy and advantages of MR, using a barium sulfate enema in noninvasive, preoperative diagnosis of a colonic lipoma, thus facilitating appropriate management of the patient.     

The effect of preoperative total parenteral nutrition on surgery outcomes

The effect of preoperative total parenteral nutrition (TPN) on morbidity and mortality was studied in medical records of discharged surgical patients. Patients were classified into two groups on the basis of their ability to meet established criteria for malnutrition and the use of preoperative or postoperative TPN. The control group consisted of 44 patients who received TPN only after surgery or for less than 5 days preoperatively. The experimental group consisted of 26 patients who received treatment for at least 5 days before surgery and/or after surgery. Nutrition parameters measured included serum albumin, total lymphocyte count, hemoglobin, weight, and percent weight loss. Major septic complications (MSC) considered were intra-abdominal sepsis, wound dehiscence, septicemia, and pneumonia. Other complications included respiratory failure, congestive heart failure, fistulas, urinary tract infection, shock, and death. The experimental group showed improvements after surgery in the nutritional parameters listed and had a lower incidence of morbidity and mortality. Deficits in serum albumin, total lymphocyte count, and weight losses greater than or equal to 10% have been significantly (p less than .01) linked to the incidence of MSC. MSC also has been more frequently noted among patients who did not have TPN prior to surgery and who died following surgery. Therefore, preoperative TPN does appear to make a difference in the outcome of surgery.     

Renal peripelvic lymphatic cysts (lymphangiomas) associated with generalized lymphangiomatosis.

Renal peripelvic lymphatic cysts (lymphangiomas) are usually seen as an isolated finding. They appear as multiple mass lesions with low attenuation on computed tomography (CT), and show no contrast enhancement. We present a case of renal peripelvic lymphatic cysts associated with generalized lymphangiomatosis, and examined with magnetic resonance imaging (MRI), CT, and lymphangiography. Multiplanar MRI demonstrated the extent of disease, including retroperitoneal lesions. The lesions had low-signal intensity on T1-weighted and high-signal intensity on T2-weighted images. The diagnosis of generalized lymphangiomatosis was verified by renal sinus cyst puncture, lymphangiography, and tissue biopsy.     

Renal peripelvic lymphatic cysts (lymphangiomas) associated with generalized lymphangiomatosis

Renal peripelvic lymphatic cysts (lymphangiomas) are usually seen as an isolated finding. They appear as multiple mass lesions with low attenuation on computed tomography (CT), and show no contiast enhancement. We present a case of renal peripelvic lymphatic cysts associated with generalized lymphangiomatosis, and examined with magnetic resonance imaging (MRI), CT, and lymphangiography. Multiplanar MRI demonstrated the extent of disease, including retroperitoneal lesions. The lesions had low-signal intensity on T1-weighted and high-signal intensity on T2-weighted images. The diagnosis of generalized lymphangiomatosis was verified by renal sinus cyst puncture, lymphangiography, and tissue biopsy.     

CT Findings of retroperitoneal malignant mesenchymoma

Malignant mesenchymoma (MM) is a rare mesenchymal neoplasm which, by definition, demonstrates at least two distinct types of malignant mesenchymal differentiation. We present the computed tomographic (CT) findings of a 42-year-old female with a pathologically proven retroperitoneal MM consisting of osteoid production combined with foci of liposarcoma and Kaposi sarcoma. MM should be considered along with extraosseous osteosarcoma and teratoma in the differential diagnosis for unusual large heterogeneous retroperitoneal masses with massive calcification.     

Estimation of average treatment effects among multiple treatment groups by using an ensemble approach

In observational studies, generalized propensity score (GPS)–based statistical methods, such as inverse probability weighting (IPW) and doubly robust (DR) method, have been proposed to estimate the average treatment effect (ATE) among multiple treatment groups. In this article, we investigate the GPS-based statistical methods to estimate treatment effects from two aspects. The first aspect of our investigation is to obtain an optimal GPS estimation method among four competing GPS estimation methods by using a rank aggregation approach. We further examine whether the optimal GPS-based IPW and DR methods would improve the performance for estimating ATE. It is well known that the DR method is consistent if either the GPS or the outcome models are correctly specified. The second aspect of our investigation is to examine whether the DR method could be improved if we ensemble outcome models. To that end, bootstrap method and rank aggregation method are used to obtain the ensemble optimal outcome model from several competing outcome models, and the resulting outcome model is incorporated into the DR method, resulting in an ensemble DR (enDR) method. Extensive simulation results indicate that the enDR method provides the best performance in estimating the ATE regardless of the method used for estimating GPS. We illustrate our methods using the MarketScan healthcare insurance claims database to examine the treatment effects among three different bones and substitutes used for spinal fusion surgeries. We draw conclusions based on the estimates from the enDR method coupled with the optimal GPS estimation method.