Histological study of human gallbladder

Background & objectives: Gallbladder is one of the organs having a wide spectrum of diseases ranging from congenital anomalies, calculi and its complications, non-inflammatory, inflammatory to the neoplastic lesions. Gallstones are one of the major causes of morbidity and mortality all over the world affecting 10% of adult population. While Gallbladder cancer is a disease of the elderly; it affects patients in their 70s, with a female to male ratio 5:1. The aim was to study the distribution with respect to age and sex and the usefulness of histological evaluation of gallbladder. Methods: This is a retrospective study of 100 cases of gallbladder lesions during the period of April 2010 to October 2011. Results: Lesions of gallbladder were more common seen in females with a male to female ratio of 1:2.3. Gallbladder lesions were more commonly found in 4 th & 5 th decades of the patients. Out of 100 cases, Non- neoplastic lesions found in 95 cases (95%) and Neoplastic lesion found in 5 cases (5%) with the ratio being 19:1. The commonest histological observation found was chronic calculous cholecystitis in 46 cases (46%) followed by acute calculous cholecystitis in 9 cases (9%). Conclusion: Female in their 4 th decade are common sufferer of Gallbladder diseases. Gallstones and their consequences are the major factors for histomorphological changes of cholecystitis. Histological examination help where adjuvent treatment is depend up on grade, severity & Extent of invasion and also to rule out suspicion about malignancy.


Introduction
Gallbladder is one of the organs having a wide spectrum of diseases ranging from congenital anomalies, calculi and its complications, non-inflammatory, inflammatory to the neoplastic lesions. So the classification of various histomorphological types of gallbladder lesions is important to categorize into non-neoplastic and neoplastic lesions of gallbladder. 1 Gallstones are one of the major causes of morbidity and mortality all over the world. It affects 10% of adult population. Its incidence increases progressively with age. Stones in the gallbladder most likely to enter in common bile duct and prevent bile flow into duodenum, hence leading to obstructive or surgical jaundice.
Gallbladder cancer is a disease of the elderly; it affects patients in their 70s, with a female to male ratio 5:1. Gallbladder carcinoma is known as an aggressive malignancy, with most large series reporting 5-year survival rates of 5-15%. In 25% of the patients the cancer is localised to gallbladder wall, in 35% it is spread beyond the wall to adjuvant soft tissue, and in 45% distant metastases occur.
Cholecystectomy is a common surgical procedure. Fortunately, gallbladder cancer is found in approximately 1% of all cholecystectomies for cholelithiasis in spite of the close relationship between gallstones and gallbladder cancer. Gallstones are present in 75-90% of gallbladder cancers.
Diseases of gallbladder are manifested as biliary pain in epigastrium and right upper quadrant of abdomen, radiating to interscapular area, right scapula and shoulder, associated with nausea, vomiting, jaundice, anorexia, fever and chills. Identification of gallbladder lesions requires proper investigations including plain abdominal x-ray, trans-abdominal ultrasonography, radioisotope scans, and proper histological examination. The value of histological examination is well explained in patients with gallbladder lesions where adjuvant treatment is dependent upon grade, severity and extent of invasion of disease. Many patients may be suspected of having a malignancy on pre-operative assessment in these cases histological examination may aid to rule out suspicion.
This study was aim to study the distribution with respect to age and sex and the usefulness of histological evaluation of Gallbladder. The specimens were fixed in 10% formalin for 24-48 hours. Tissues were taken from the pathological lesions and processed by standard technique in the Yorco Automatic Tissue Processor for 24 hours; and paraffin blocks were made. The blocks were cut to give 4-5 micron thick sections and stained with haematoxylin and eosin. The slides were made, labelled and mounted in DPX. All the slides were studied with 10X and 40X magnification of light microscope. 2, 3

Result
Out of 100 cases, 70 cases were of females and 30 cases were of males. Lesions of gallbladder were more common in females than in males with a male to female ratio of 1:2.3. Lesions of gallbladder were most common in the 4 th and 5 th decades, with 25% of cases occurring in the 4 th decade and 26% occurring in the 5 th decade. The youngest patient was of 8 years and the oldest patient was of 75 years. Out of 100 cases we studied, Non-neoplastic lesions constituted 95 cases (95%) and Neoplastic lesion constitute 5 cases (5%) with the ratio being 19:1. Total 100

Figure 1: Normal Human Gall-bladder Histology [ X40 ]
On histological examination gallbladder shows infiltration of lymphocytes, macrophages and plasma cells in lamina propria. Epithelium shows variable changes from atrophic or hyperplastic to dysplastic. In 9 cases it shows edema of the epithelium with infiltration of lymphocytes suggesting of acute cholecystitis [ Figure 2]. Also there is presence of outpouchings of mucosa through the muscles of Gallbladder wall (Rokitansky-Aschoff Sinuses) in more than 50 % cases. Which are characteristic but not diagnostic feature of chronic cholecystitis [ Figure 3]. Also muscle layer shows changes of hypertrophy. The commonest histomorphological observation in the present study was chronic calculous cholecystitis 46 cases (46%) followed by acute calculous cholecystitis 9 cases (9%). While in present study Benign lesions of gallbladder were 3 cases (3%) and malignant lesions were 2 cases (2%).

Discussion
Gallstone & its complications are one of the major causes of morbidity and mortality all over the world affecting 10% of adult population. While Gallbladder cancer is a disease of the elderly; it affects patients in their 70s.
In present study lesions of gallbladder were more common in females than in males with a male to female ratio of 1:2.  11 studied that neoplastic lesions developed in patients of age more than 50 yrs and maximum in age group 50 to 70 years. The present study is comparable to the above studies (4 th and 5 th decades).

Conclusion
Female in their 4 th decade are common sufferer of Gallbladder diseases. Gallstones and their consequences are the major factors for histomorphological changes of cholecystitis. Histological examination help, where adjuvent treatment is depend up on grade, severity & Extent of invasion and also to rule out suspicion about malignancy.