A brief summary of 60 years of autopsies performed at the Department of Pathology at Kansai Medical University is described. The 6,108 autopsy cases performed from 1951 to 2010 were analyzed based on the main pathological diagnoses. The number of autopsies per year gradually increased and peaked at 225 in 1981; then, the annual number of autopsies decreased until reaching its lowest level (45 cases) in 2002. Nearly 60 autopsies per year have been performed in the last decade. The numbers and frequencies of stillborn and newborn cases were high in the late 1950s and early ‘60s and then gradually decreased due to a decrease in respiratory system disorder cases. The most frequent pathological diagnosis throughout the observation period was malignant neoplasms (range, 32–63%; mean, 48%). According to age distribution, in both males and females, a small peak was seen at 0–4 years of age; then, starting from the late teens, the cases increased in parallel to aging and peaked at 65–69 years of age. The male-to-female ratio was 1.9:1. The frequency of autopsy cases marked by multiple primary cancers has increased over the years. For the past 30 years, heart disease cases exceeded cerebrovascular disease cases. Era-specific diseases included: a high frequency of tuberculosis cases in the early ‘50s that dramatically decreased thereafter; Japanese encephalitis cases in the mid-‘60s; and acquired immunodeficiency syndrome (AIDS) cases in the late ‘80s to ‘90s. And, although rare, deep mycosis as was the main pathological diagnosis (cause of death) has gradually increased since the ‘60s. Additionally, malignant mesothelioma cases increased in the ‘90s due to high asbestos consumption in the high economic growth period (mid-‘50s to mid-‘70s). Changes in autopsy cases at Kansai Medical University during a 60-year period (from 1951 to 2010) are described.
When comparing a single stroke dissection maneuver among surgeons with differing experience levels, there are major differences in the force applied to the instrument tip. However, it is difficult for expert surgeons to explain to novice surgeons in training the appropriate force during dissection procedure. We developed the force measurement system which can quantify the force pattern during single-stroke laparoscopic dissection maneuvers to reveal the factors related to expertise. Expert surgeons apply the most efficient vertical forces to make an initial dissection point and then change to the horizontal direction to separate surrounding tissues from the target organ. Measuring instrument tip force could help in understanding and improving the safety margin in laparoscopic surgical dissection.
Pancreatic enlargement, a high serum immunoglobulin G4 (IgG4) level, and infiltration of IgG4-positive cells are characteristic of Type 1 autoimmune pancreatitis (AIP). Patients with AIP sometimes present with a pancreatic focal mass, which mimics pancreatic ductal adenocarcinoma (PDA), resulting in unnecessary surgery. The high serum IgG4 level may be helpful in distinguishing Type 1 AIP from PDA. However, recently, some patients with PDA present with a high serum IgG4 level. Therefore, we performed IgG4 immunohistochemistry in PDA. The ratio of cases with >10 positive cells/hpf of IgG4-positive cells was 1/21 (5%) in the PDA area and 2/21 (10%) in the obstructive pancreatitis area, characterized by upstream dilation of the main pancreatic duct by the cancer. The ratio of cases >40% IgG4-positive cells per IgG-positive cells (IgG4/IgG) was 9/21 (43%) in the PDA area, 6/21 (29%) in the peritumoral pancreatitis area, and 3/21 (14%) in the obstructive pancreatitis area. Lately, we have come to diagnose pancreatic diseases using endoscopic ultrasound. The infiltration of IgG4-positive cells is also found in obstructive pancreatitis along with PDA. Therefore, clinicians should be very careful in making a differential diagnosis of PDA and Type 1 AIP based on the number of IgG4-positive cells and the ratio of IgG4/IgG, especially if they only have a small sample taken by endoscopic ultrasound-guided fine needle aspiration biopsy (EUS-FNAB).