Neoplasm

2005175 The value of apparent diffusion coefficients (ADCs) in the diagnosis of malignant bone neoplasms. MA Ling(马玲), et al. Dept Diag Radi-ol, 1st Affili Hosp Sun Yat-sen Univ, Guangzhou 510080. Chin J Radiol, 2004;38(11):1129-1134. Objective: To evaluate the value of apparent diffusion coefficients (ADCs) in the diagnosis of malignant bone neoplasms. Methods: Eighteen cases with     

Mucinous cystadenoma of the appendix associated with adenocarcinoma of the sigmoid colon and hepatocellular carcinoma of the liver： Report of a case

Mucinous cystadenoma of the appendix is a rarecondition and represents one of the three entities withthe common name mucocele of the appendix.It ischaracterized by a cystic dilatation of the lumen withstasis of mucus inside it.Histopathologically mucoceleis divided into three groups:focal or diffuse mucosalhyperplasia,mucinous cystadenoma and mucinouscystadenocarcinoma.This condition is often associatedwith other neoplasia,especially adenocarcinoma ofthe colon and ovaries.We here describe a 57 year oldmale patient who presented with abdominal discomfort,constipation,fresh blood in stool and frequent urination.He had a big cystadenoma of the appendix associatedwith adenocarcinoma of the colon and hepatocellularcarcinoma of the liver.The patient underwent righthaemicolectomy,sigmoid colon resection and segmentalresection of the liver.Now 3 years later he has noevidence of disease relapse.According to this,westress the need of accurate preoperative diagnosis andintraoperative exploration of the whole abdomen in thesepatients.     

Mucinous nonneoplastic cyst of the pancreas： A truly novel pathological entity？

Recently, a novel and distinct pancreatic cystic tumor termed "mudnous nonneoplastic" cyst was described in the literature. We report our experience with a 71-year-old female with a cystic tumor in the body of the pancreas demonstrating features suggestive of this diagnosis. We also review the literature regarding this "novel" pathological entity and discuss critically its existence and its differential diagnoses.     

Mucinous cystic neoplasm of the pancreas: Is surgical resection recommended for all surgically fit patients?

BackgroundSurgical removal of mucinous cystic neoplasms (MCNs) is usually recommended because of the risk of malignancy. However, increased experience of MCNs suggests that the incidence of invasion is lower than had been thought. This study was designed to establish more reasonable surgical indications for MCN through re-assessment using strict pathologic diagnostic criteria.MethodsNinety-four patients who underwent surgical removal of MCNs at Seoul National University Hospital from 1991 to 2012 were retrospectively analyzed. Pathologic results were re-evaluated by an experienced pathologist. Medical records and radiologic images were reviewed to determine factors predicting malignancy.ResultsOf the 94 patients, 4 were found to have intraductal papillary mucinous neoplasms (IPMNs). Of the 90 MCNs, 60 (66.7%) were low-grade, 21 (23.3%) were intermediate-grade, and 5 (5.5%) were high-grade dysplasias; and 4 (4.4%) were invasive carcinoma. Mural nodules on CT scan (p = 0.005) and abnormal serum CA19-9 concentration (p = 0.029) were significant predictors of malignancy. All MCNs less than 3 cm in size with normal serum tumor markers were benign and all malignant MCNs had cyst fluid CA19-9 over 10,000 units/ml. The five year disease specific survival rates were 98.8% for all patients and 75.0% for those with invasive MCNs.ConclusionMCNs had a low prevalence of malignancy. Regardless of the histological grade, long-term outcome was excellent. Therefore, in the absence of specific symptoms, surgery may not be indicated for MCNs <3 cm without mural nodules or elevated serum tumor markers. Validation by a prospective study with very careful design is needed.     

Mucinous carcinoma—Just another colon cancer?

The significance of mucinous carcinoma has been controversial since first described by Parham in 1923. Previous reports have suggested that mucinous tumors affect young patients, involve the more proximal colon, are more advanced at diagnosis, and have a poorer prognosis than nonmucinous colon carcinoma. More recent reports have refuted these results. In an effort to clarify the significance of mucinous histology, a retrospective review of cases of invasive colon cancer treated at the Ochsner Clinic between 1982 and 1985 was undertaken. Mucinous adenocarcinoma, as defined by 50 percent mucin, was found in 52 patients. During the same period, 343 nonmucinous adenocarcinomas were resected. The mean age, distribution within the colon, stage at diagnosis, and survival of mucinous carcinoma patients were compared with those with nonmucinous tumors. Mucinous tumors presented at a statistically significant more advanced stage (38 percent vs. 22 percent Dukes C lesions;P <0.01). No significant differences were seen in age at presentation, distribution within the colon, or stage-for-stage survival when the entire group was analyzed. Mucinous carcinomas of the rectum occurred at an advanced stage more frequently (P <0.05) than nonmucinous rectal carcinomas and had a markedly worse five-year survival (11 percent vs. 57 percent;P <0.002).     

When does the good of the group override the advantage of the individual?

In a system of N populations of n reproductive individuals apiece, in which each population has constant variance v² and lasts L generations, group selection on a quantitative character has a reasonable chance of overriding selection within populations if (and only if) the populations never exchange migrants, each population is founded by colonists from a single parent population, and the number of populations exceeds the effective number of reproductive individuals per population. If each population derives from a single parent population, then the exchange of a single successful migrant per population per L generations can triple the strength of group selection required to overcome a given selection within populations. If populations exchange no migrants, then the derivation of one in every N populations from two equally represented parents (while the others all derive from a single parent) doubles the strength of group selection required to prevail. Group selection is accordingly likely to be effective only in certain categories of parasites.     

Stochastic simulations of the exponential-beta function as an assessment of the validity of the choice of the Wagner-Nelson method for the analysis of ¹³C-octanoic acid breath tests

A compartmental model that generates the exponential-beta function μkβ(1 - e(-kt))(β - 1)?e(-kt) in order to run stochastic simulations has been constructed. The mathematical considerations that lead to the development of the model and the comparison of its performance with real data sets obtained from the studies of gastric emptying in healthy volunteers using 13C-octanoic acid breath tests are demonstrated. Stochastic simulations have been used to introduce randomness. These confirmed the choice of an exponential-beta function to model the physiological system, as agreement was obtained between experimental and theoretical data. The comparisons were made by visual inspection only, as the intention was to demonstrate that the stochastic exponential-β model would generate the full range of observed curve shapes.     

Anterior fissure of the right liver — the third door of the liver

Background/Purpose

Although the anterior segment of the liver has been divided into segments 8 and 5, we have, during surgical or interventional procedures, occasionally encountered patients in whom the right anterior portal vein does not bifurcate into the superior and inferior branches. Thus, the in vivo anatomy of the right liver was reevaluated to clarify the segmental anatomy.

Methods

We evaluated the hepatic venous and portal ramification patterns, using three-dimensional images reconstructed from computed tomography. In addition, liver volumetry was performed.

Results

All branches arising from the anterior trunk were divided into two groups: the right ventral portal branches (RVP) and the right dorsal portal branches (RDP), and the anterior fissure vein crossed between the RVP and RDP. The ventral and dorsal regions of the anterior segment were approximately equal from a volumetric point of view.

Conclusions

The anterior segment seems to be divided into the ventral and dorsal segments by the anterior fissure, and we propose a reclassification of the right liver that divides the right liver into three segments. Dissection of the parenchyma along the anterior fissure makes the third door of the liver open, resulting in the exposing of all Glissonian pedicles of the right liver. The introduction of our segmental anatomy and surgical procedure will allow more systematic and limited liver resections.