Current assessment and future directions of surgical skills laboratories

BACKGROUND: Educational, medicolegal, and financial constraints have pushed surgical residency programs to find alternative methods to operating room teaching for surgical skills training. Several studies have demonstrated that the use of skills laboratories is effective and enhances performance; however, little is known about the facilities available to residents. STUDY DESIGN: A survey was distributed to 40 general surgery program directors who, in an earlier questionnaire, indicated that they had skills laboratory facilities at their institutions. The survey included the following sections: demographics, facilities, administrative infrastructure, curriculum, learners, and opinions/thoughts of program directors. RESULTS: Of the 34 program directors that completed the survey, 76% are from a university program. The average facility is 1400 square feet, and most skills laboratories are located in the hospital. Nearly all skills facilities have dry laboratories (90%), and the most common equipment is box trainers (90%). Average start-up costs were $450,000. Sixty-two percent of programs have a skills curriculum for residents. Responders agreed that skills laboratories have a high value and should be part of residency curricula. CONCLUSIONS: The results of this survey provide a preliminary view of skills laboratories. There is variation in the size, location, and availability of simulators in skills laboratory facilities. Variations also exist in types of curricula formats, subspecialties who make use of the laboratory, and some administrative approaches. There is strong agreement among respondents that skills laboratories are a necessary and valuable component of residency education. Results also indicated concerns for recruiting faculty to teach in the skills laboratory, securing ongoing funding, and implementing a skills laboratory curriculum.     

Relationship of procedural numbers with meaningful procedural autonomy in general surgery residents

Background

Concerns exist regarding the competency of general surgery graduates with performing core general surgery procedures. Current competence assessment incorporates minimal procedural numbers requirements.

Periareolar injection for localization of sentinel nodes in breast cancer patients

The goal of this study was to evaluate the periareolar injection of technetium 99m sulfur colloid to identify axillary sentinel nodes and compare the number of sentinel lymph nodes identified with preoperative lymphoscintigraphy to intraoperative biopsy using a handheld gamma probe. A total of 104 consecutive patients diagnosed with invasive breast cancer participated in this prospective study, with 81 patients receiving an intradermal periareolar injection and 23 patients receiving an intradermal peritumoral injection of filtered technetium 99m sulfur colloid. Preoperative lymphoscintigraphy was performed for sentinel node mapping and localization. In addition to selective sentinel node biopsy, axillary dissection was performed on all patients to determine false-negative rates. Routine histologic staining was performed on all identified nodes, along with immunohistochemical staining of sentinel nodes negative on initial routine staining. With an intradermal periareolar injection, the sentinel node identification rate was 91.4% (74/81), axillary metastatic rate 35.1% (26/74), sentinel node positive only 61.5% (16/26), and false negative 3.8% (1/26). With an intradermal peritumoral injection, the sentinel node identification rate was 91.3% (21/23), axillary metastatic rate 42.9% (9/21), sentinel node positive only 88.9% (8/9), and false negative 0% (0/9). A total of 241 sentinel nodes were identified with biplanar lymphoscintigraphy and 173 sentinel nodes were harvested during surgery, yielding a 28.2% increase in sentinel nodes identified with lymphoscintigraphy. This study demonstrates that intradermal periareolar injection of filtered technetium 99m sulfur colloid is successful in identifying axillary sentinel nodes with a low false-negative rate. Preoperative lymphoscintigraphy aids in the identification and surgical planning of sentinel node biopsy and provides an objective measure of surgical performance.     

Follow-up study after resection of intraductal papillary mucinous neoplasm of the pancreas; special references to the multifocal lesions and development of ductal carcinoma in the remnant pancreas

BackgroundFrequency and characteristics of metachronous occurrence of multifocal intraductal papillary mucinous neoplasms (IPMNs) or distinct pancreatic ductal adenocarcinomas (PDACs) in the remnant pancreas during follow-up evaluation after pancreatectomy for IPMNs have not been well known. The aim of this study was to investigate the outcomes after resection of IPMNs, especially focusing on the metachronous occurrence of multifocal IPMNs and distinct PDACs.MethodsMedical records of 172 patients who underwent resection of IPMNs were reviewed retrospectively, and the data regarding the occurrence of metachronous IPMNs or PDACs in the remnant pancreas during a mean postoperative follow-up period of 64 months were collected.ResultsThe incidence including synchronous and metachronous multifocal occurrence of IPMNs was 20% (34 of 172), and that of distinct PDACs was 9.9% (17 of 172). Ten metachronous IPMNs developed in the remnant pancreas after a mean time of 23 postoperative months (range, 12–84 mo), and 2 with main duct IPMNs (both were carcinoma in situ) required remnant pancreatectomy. Six distinct PDACs developed in the remnant pancreas after a mean time of 84 postoperative months (range, 12–150 mo). Four of them were found to have a tumor with a size of less than 2 cm, whereas the remaining 2 PDACs were found to be unresectable more than 10 years after resection of IPMNs.ConclusionsIntense long-term follow-up evaluation is necessary for the early detection of metachronous occurrence of distinct PDACs as well as malignant IPMNs after resection of IPMNs.     

Loss of myoepithelial cell characteristics in metastasizing rat mammary tumors relative to their nonmetastasizing counterparts

A series of WF rat mammary tumors comprising one transplantable nonmetastasizing line (MT-W9), two predominantly lymphatic (SMT-2A and SMT-077) and one lymphatic and hematogenous (MT-450) metastasizing transplantable lines, and 7,12-dimethylbenz[a]anthracene (DMBA)-induced nonmetastasizing primary tumors was examined for the presence of epithelial and myoepithelial cell characteristics with the use of immunocytochemical techniques. Tumor cells staining for myosin were only occasionally observed in a basal orientation in glandular structures in sections of DMBA-induced and MT-W9 tumors; anti-laminin serum stained the peripheries of the glandular structures in the DMBA-induced and MT-W9 tumors but failed to stain the SMT-2A and SMT-077 tumor cells. In the nonmetastasizing tumors immunologically detectable keratin occurred mainly in the outer cellular layer of glandlike structures, whereas milk fat globule membrane immunoreactivity occurred primarily in the luminal cells. Both these types of immunoreactivity were observed in MT-450 tumor cells, but the pattern of keratin staining was random. No such immunoreactivity occurred in SMT-2A or SMT-077 tumors. No tumor cell-associated staining for fibronectin was seen in any of the tumors examined, although host stromal components stained intensely. The nonmetastasizing tumors contained cuboidal epithelial cells with lumen formation, surface microvilli, and intercellular junctional complexes, together with a relatively undifferentiated elongated cell component. Other elongated cells showed hemidesmosomes, pinocytotic vesicles, tonofilaments, and small bundles of cytoplasmic filaments, suggesting gradations toward a myoepithelial phenotype. The MT-450 tumors were ultrastructurally similar to the nonmetastasizing tumors, but no features of myoepithelial cells were seen, although some cuboidal epithelial cells exhibited prominent tonofilaments. The SMT-2A and SMT-077 tumors consisted of nests of cuboidal-like cells with highly pleomorphic nuclei and much intercellular collagen. The results indicate a progressive loss of cellular differentiation characteristics, particularly those of the myoepithelial cell with increasing malignancy in this system.     

Phenotypic instability of rat mammary tumor epithelial cells

The spontaneous production of elongated derivatives by cuboidal rat mammary epithelial cells was examined with the use of a series of single-cell clones grown in tissue culture. Four representative cell lines derived from a 7,12-dimethylbenz[a]anthracene-induced mammary tumor in an inbred WF rat were examined for morphologic stability, chromosome number, presence of immunoreactive fibronectin, laminin, prekeratin, and milk fat globule membrane (MFGM) antigens, ultrastructural characteristics, and tumorigenicity in syngeneic hosts. Conversion of cuboidal to elongated cells occurred by way of apparent morphologic intermediates, examples of which were isolated and cloned. Levels of immunoreactive fibronectin and laminin were greater in the elongated than the cuboidal clones, whereas the converse was true of prekeratin. MFGM antigens were present to a variable extent in all 4 clones. When grown on 0.3% collagen gels, cells of Rama 37 CL-A3 and Rama 37CS-A2 cuboidal clones exhibited surface microvilli and desmosomes. A minority of elongated cells contained microfilamental structures and pinocytotic vesicles similar to those seen in myoepithelial cells; the remainder lacked distinguishing ultrastructural features. After injection into syngeneic recipients, Rama 37 CL-A3 cuboidal line gave rise to glandular tumors consisting of cuboidal cells arranged in acinar structures, Rama 37 E5 elongated line induced spindle cell tumors, and Rama 37 CS-A2 and Rama 37 E8 lines induced tumors containing nests of mixed spindle and cuboidal cells. The majority of these tumors failed to metastasize.     

An evaluation of study habits of third-year medical students in a surgical clerkship

BACKGROUND: This study was developed to assess study habits of medical students in a third-year surgical clerkship and to determine the relationship of these study habits to performance outcomes. METHODS: A questionnaire designed to assess medical student study habits was administered at the end of five consecutive 10-week multidisciplinary surgical clerkships. The results of questionnaires from 81 students were analyzed in respect to results on the National Board of Medical Education (NBME) surgical subtest and the multiple stations clinical examination (MSCE) given at the end of each clerkship. RESULTS: Although only 18 of the total 81 students reported studying in formal but self-directed groups, students who reported studying in a group on average scored 4 points higher on the MSCE than those who did not study in a group (P = 0.001). However, no significant differences or correlations were discovered between any of the study habits and the individual results on the NBME. CONCLUSION: Students may benefit from collaborative studying when it comes to clinical experience as demonstrated by improved performance on the MSCE.