This document summarizes tumors that can develop in liver tissue. It discusses benign and malignant primary tumors of the liver as well as metastatic tumors. The most common primary malignant tumor is hepatocellular carcinoma, which is often associated with hepatitis B and C infections and cirrhosis. Other primary malignant tumors include cholangiocarcinoma and hepatoblastoma. Metastatic tumors are more frequent than primary tumors and most commonly spread from the stomach, breast, lungs, and colon. The document provides details on the etiology, pathology, and histological features of these various tumor types.

1. TUMORS OF
LIVER TISSUE
JOEL SONY

2. HEPATIC TUMOURS
THE LIVER IS THE SITE FOR BENIGN TUMOURS, TUMOUR-LIKE LESIONS, AND
BOTH PRIMARY AND METASTATIC MALIGNANT TUMOURS. HOWEVER,
METASTATIC TUMOURS ARE MUCH MORE COMMON THAN PRIMARY
TUMOURS AND TUMOUR-LIKE LESIONS. PRIMARY HEPATIC TUMOURS MAY
ARISE FROM HEPATIC CELLS, BILE DUCT EPITHELIUM, OR MESODERMAL
STRUCTURES

3. TUMOUR-LIKE LEISONS
CYSTS IN THE LIVER MAY BE SINGLE OR MULTIPLE. THESE CYSTS ARE MAINLY OF
3 TYPES— CONGENITAL, SIMPLE (NONPARASITIC) AND HYDATID
(ECHINOCOCCUS) CYSTS
CONGENITAL CYSTS THESE ARE UNCOMMON. THEY ARE USUALLY SMALL
(LESS THAN 1 CM IN DIAMETER) AND ARE LINED BY BILIARY EPITHELIUM. THEY
MAY BE SINGLE, OR OCCUR AS POLYCYSTIC LIVER DISEASE, OFTEN ASSOCIATED
WITH POLYCYSTIC KIDNEY. ON OCCASIONS, THESE CYSTS HAVE ABUNDANT
CONNECTIVE TISSUE AND NUMEROUS DUCTS, WARRANTING THE DESIGNATION
OF CONGENITAL HEPATIC FIBROSIS
SIMPLE (NON-PARASITIC) CYSTS SIMPLE CYSTS ARE SOLITARY NON-
PARASITIC CYSTS SEEN MORE FREQUENTLY IN MIDDLE AGED WOMEN. THE CYST
IS USUALLY LARGE (UP TO 20 CM IN DIAMETER), LYING UNDERNEATH THE
GLISSON’S CAPSULE AND FI LLED WITH SEROUS FLUID. THE CYST PRODUCES A
PALPABLE MASS AND MAY BE ASSOCIATED WITH JAUNDICE.
HYDATID DISEASE (ECHINOCOCCOSIS) HYDATID DISEASE OCCURS AS A
RESULT OF INFECTION BY THE LARVAL CYST STAGE OF THE TAPEWORM,
ECHINOCOCCUS GRANULOSUS

5. BENIGN HEPATIC TUMOURS
THESE ARE UNCOMMON AND SOME OF THEM ARE INCIDENTAL AUTOPSY
FINDINGS. THESE INCLUDE HEPATOCELLULAR (LIVER CELL) ADENOMA, BILE
DUCT ADENOMA (CHOLANGIOMA) AND HAEMANGIOMA.
•HEPATOCELLULAR (LIVER CELL) ADENOMA
ADENOMAS ARISING FROM HEPATOCYTES ARE RARE AND ARE REPORTED IN
WOMEN IN REPRODUCTIVE AGE GROUP IN ASSOCIATION WITH USE OF ORAL
CONTRACEPTIVES, SEX HORMONE THERAPY AND WITH PREGNANCY. THE
TUMOUR PRESENTS AS INTRAHEPATIC MASS THAT MAY BE MISTAKEN FOR
HEPATO CELLULAR CARCINOMA AND MAY RUPTURE CAUSING SEVERE
INTRAPERITONEAL HAEMORRHAGE
THE TUMOUR USUALLY OCCURS SINGLY BUT ABOUT 10% ARE MULTIPLE. IT IS
PARTLY OR COMPLETELY ENCAPSULATED AND SLIGHTLY LIGHTER IN COLOUR
THAN ADJACENT LIVER OR MAY BE BILE-STAINED.
LIVER CELL ADENOMAS ARE COMPOSED OF SHEETS AND CORDS OF
HEPATOCYTES WHICH MAY BE NORMAL-LOOKING OR MAY SHOW SLIGHT
VARIATION IN SIZE AND SHAPE BUT NO MITOSES

7. •BILE DUCT ADENOMA (CHOLANGIOMA)
INTRAHEPATIC OR EXTRAHEPATIC BILE DUCT ADENOMA IS A RARE BENIGN
TUMOUR. THE TUMOUR MAY BE SMALL, COMPOSED OF ACINI LINED BY
BILIARY EPITHELIUM AND SEPARATED BY VARIABLE AMOUNT OF
CONNECTIVE TISSUE, OR ARE LARGER CYSTADENOMAS HAVING LOCULI
LINED BY BILIARY EPITHELIUM.

8. •HAEMANGIOMA
HAEMANGIOMA IS THE COMMONEST BENIGN TUMOUR OF THE LIVER.
MAJORITY OF THEM ARE ASYMPTOMATIC AND DISCOVERED INCIDENTALLY.
RARELY, A HAEMANGIOMA MAY RUPTURE INTO THE PERITONEAL CAVITY.
HAEMANGIOMAS APPEAR AS SOLITARY OR MULTIPLE, CIRCUMSCRIBED,
RED-PURPLE LESIONS, COMMONLY SUBCAPSULAR AND VARYING FROM A FEW
MILLIMETRES TO A FEW CENTIMETRES IN DIAMETER.
HAEMANGIOMA OF THE LIVER SHOWS CHARACTERISTIC LARGE,
CAVERNOUS, BLOOD-FI LLED SPACES, LINED BY A SINGLE LAYER OF
ENDOTHELIUM AND SEPARATED BY CONNECTIVE TISSUE

9. MALIGNANT HEPATIC TUMOUR
AMONG THE PRIMARY MALIGNANT TUMOURS OF THE LIVER,
HEPATOCELLULAR (LIVER CELL) CARCINOMA ACCOUNTS FOR APPROXI
MATELY 85% OF ALL PRIMARY MALIGNANT TUMOURS,
CHOLANGIOCARCINOMA FOR ABOUT 5-10%, AND INFREQUENTLY MIXED
PATTERN IS SEEN. TH E REMAINDER ARE RARE TUMOURS THAT INCLUDE
HEPATOBLASTOMA, HAEMANGIOSARCOMA (ANGIO SARCOMA) AND
EMBRYONAL SARCOMA. HEPATIC HAEMAN GIOSARCOMA AND
EMBRYONAL SARCOMA RESEMBLE IN MORPHO LOGY WITH THEIR
COUNTERPARTS ELSEWHERE IN THE BODY

11. •HEPATOCELLULAR CARCINOMA
HEPATOCELLULAR CARCINOMA (HCC) OR LIVER CELL CARCINOMA, ALSO
TERMED AS HEPATOMA, IS THE MOST COMMON PRIMARY MALIGNANT
TUMOUR OF THE LIVER. THE TUMOUR SHOWS MARKED GEOGRAPHIC
VARIATIONS IN INCIDENCE WHICH IS CLOSELY RELATED TO HBV AND HCV
INFECTION IN THE REGION.

12. ETIOPATHOGENESIS
1. RELATION TO HBV INFECTION GENESIS OF HCC IS LINKED TO PROLONGED
INFECTION WITH HBV. TH E EVIDENCE IN SUPPORT IS BOTH EPIDEMIOLOGIC
AND DIRECT.
2. RELATION TO HCV INFECTION LONG-STANDING HCV INFECTION HAS EMEREGED
AS A MAJOR FACTOR IN THE ETIOLOGY OF HCC, GENERALLY AFTER MORE THAN
30 YEARS OF INFECTION
3. RELATION TO CIRRHOSIS CIRRHOSIS OF ALL ETIOLOGIC TYPES IS MORE
COMMONLY ASSOCIATED WITH HCC BUT THE MOST FREQUENT ASSOCIATION IS
WITH MACRONODULAR POST-NECROTIC CIRRHOSIS.
4. RELATION TO ALCOHOL IT HAS BEEN OBSERVED THAT ALCOHOLICS HAVE ABOUT
FOUR-FOLD INCREASED RISK OF DEVELOP ING HCC. IT IS POSSIBLE THAT
ALCOHOL MAY ACT AS CO-CARCINOGEN WITH HBV OR HCV INFECTION, BUT
ALCOHOL DOES NOT APPEAR TO BE A HEPATIC CARCINOGEN
5. MYCOTOXINS AN IMPORTANT MYCOTOXIN, AFL ATOXIN B1, PRODUCED BY A
MOULD ASPERGILLUS FL AVUS, CAN CONTAMINATE POORLY STORED WHEAT
GRAINS OR GROUNDNUTS, IN HOT AND HUMID PLACES
6. CHEMICAL CARCINOGENS A NUMBER OF CHEMICAL CARCINOGENS CAN
INDUCE LIVER CANCER IN EXPERIMENTAL ANIMALS
7. MISCELLANEOUS FACTORS LIMITED ROLE OF VARIOUS OTHER FACTORS IN
HCC HAS BEEN OBSERVED.

13. MACROSCOPICPATTERNSOFHEPATOCELLULARCARCINOMA
HCC MAY FORM ONE OF THE FOLLOWING 3 PATTERNS OF GROWTH, IN
DECREASING ORDER OF FREQUENCY
i) EXPANDING TYPE: MOST FREQUENTLY, IT FORMS A SINGLE,
YELLOWBROWN, LARGE MASS, MOST OFTEN IN THE RIGHT LOBE OF THE
LIVER WITH CENTRAL NECROSIS, HAEMORRHAGE AND OCCASIONAL
BILESTAINING . IT MAY BE DECEPTIVELY ENCAPSU LATED.
ii) MULTIFOCAL TYPE: LESS OFTEN, MULTIFOCAL, MULTIPLE MASSES, 3-5 CM
IN DIAMETER, SCATTERED THROUGHOUT THE LIVER ARE SEEN.
iii) INFI LTRATING (SPREADING) TYPE: RARELY, THE HCC FORMS DIFF USELY
INFILTRATING TUMOUR MASS

14. HISTOLOGICALPATTERNS
i) TRABECULAR OR SINUSOIDAL PATTERN IS THE MOST COMMON. TH E
TRABECULAE ARE MADE UP OF 2-8 CELL WIDE LAYERS OF TUMOUR
CELLS SEPARATED BY VASCULAR SPACES OR SINUSOIDS WHICH ARE
ENDOTHELIUM-LINED
ii) PSEUDOGLANDULAR OR ACINAR PATTERN IS SEEN SOMETIMES. TH E
TUMOUR CELLS ARE DISPOSED AROUND CENTRAL CYSTIC SPACE
FORMED BY DEGENERATION AND BREAKDOWN IN SOLID
TRABECULAE.
iii) COMPACT PATTERN RESEMBLES TRABECULAR PATTERN BUT THE
TUMOUR CELLS FORM LARGE SOLID MASSES WITH INCONSPICUOUS
SINUSOIDS.
iv) SCIRRHOUS PATTERN IS CHARACTERISED BY MORE ABUNDANT
FIBROUS STROMA

15. •FIBROLAMELLAR CARCINOMA
A CLINICOPATHOLOGIC VARIANT OF THE HCC IS FIBROLAMELLAR
CARCINOMA OF THE LIVER FOUND IN YOUNG PEOPLE OF BOTH
SEXES. THE TUMOUR FORMS A SINGLE LARGE MASS WHICH MAY
BE ENCAPSULATED AND OCCURS IN THE ABSENCE OF CIRRHOSIS
HISTOLOGICALLY, THE TUMOUR IS COMPOSED OF EOSINO PHILIC
POLYGONAL CELLS (ONCOCYTES) FORMING CORDS AND NESTS
WHICH ARE SEPARATED BY BANDS OF FIBROUS STROMA
TH E USUAL FEATURES CONSIST OF HEPATOMEGALY WITH
PALPABLE MASS IN THE LIVER, RIGHT UPPER QUADRANT PAIN
OR TENDERNESS, AND LESS OFTEN, JAUNDICE, FEVER AND
HAEMORRHAGE FROM OESOPHAGEAL VARICES

17. SPREAD THE HCC CAN HAVE BOTH INTRAHEPATIC AND EXTRAHEPATIC
SPREAD WHICH FAITHFULLY REPRODUCES THE STRUCTURE OF THE PRIMARY
TUMOUR:
•INTRAHEPATIC SPREAD OCCURS BY HAEMATOGENOUS ROUTE AND FORMS
MULTIPLE METASTASES IN THE LIVER.
•EXTRAHEPATIC SPREAD OCCURS VIA HEPATIC OR PORTAL VEINS TO
DIFFERENT SITES, CHIEFLY TO LUNGS AND BONES, AND BY LYMPHATIC
ROUTE TO REGIONAL LYMPH NODES AT THE PORTA HEPATIS AND TO
MEDIASTINAL AND CERVICAL LYMPH NODES.
THE CAUSES OF DEATH FROM THE HCC ARE CACHEXIA, MASSIVE
BLEEDING FROM OESOPHAGEAL VARICES, AND LIVER FAILURE WITH
HEPATIC COMA. USUALLY, SURVIAL AFTER DIGNOSIS OF HCC IS LESS THAN 2
YEARS.

18. •CHOLANGIOCARCINOMA
CHOLANGIOCARCINOMA IS THE DESIGNATION USED FOR CARCINOMA
ARISING FROM BILE DUCT EPITHELIUM WITHIN THE LIVER (PERIPHERAL
CHOLANGIOCARCINOMA). CARCINOMAS ARISING FROM THE LARGE HILAR
DUCTS (HILAR CHOLANGIOCARCINOMA) AND FROM EXTRAHEPATIC DUCTS
ARE TERMED BILE DUCT CARCINOMAS
MORPHOLOGIC FEATURES : THE TUMOUR IS FIRM TO HARD AND WHITISH.
THE TUMOUR HAS GLANDULAR STRUCTURE. TH E TUMOUR CELLS
RESEMBLE BILIARY EPITHELIUM BUT WITHOUT BILE SECRETION. TH EY
FORM VARIOUS PATTERNS SUCH AS TUBULAR, DUCTULAR OR PAPILLARY.

19. •HEPATOBLASTOMA (EMBRYOMA)
HEPATOBLASTOMA IS A RARE MALIGNANT TUMOUR ARISING FROM
PRIMITIVE HEPATIC PARENCHYMAL CELLS. IT PRESENTS BEFORE THE AGE OF 2
YEARS AS PROGRESSIVE ABDOMINAL DISTENSION WITH ANOREXIA, FAILURE
TO THRIVE, FEVER AND JAUNDICE. IT IS MORE COMMON IN BOYS. THE
CONCENTRATION OF SERUM AFP IS HIGH. THE TUMOUR GROWS RAPIDLY
AND CAUSES DEATH BY HAEMORRHAGE, HEPATIC FAILURE OR WIDESPREAD
METASTASES.
THE TUMOUR IS CIRCUM SCRIBED AND LOBULATED MASS MEASURING 5-
25 CM IN SIZE, HAVING AREAS OF CYSTIC DEGENERATION, HAEMOR RHAGE
AND NECROSIS.

20. HEPATOBLASTOMA CONSISTS OF 2 COMPONENTS:
I) EPITHELIAL COMPONENT CONTAINS 2 TYPES OF CELLS— ‘EMBRYONAL’
HEPATOCYTES ARE SMALL WITH DARK-STAINING, HYPER CHROMATIC
NUCLEI AND SCANTY CYTOPLASM, WHILE ‘FOETAL’ HEPATOCYTES ARE
LARGER WITH MORE CYTOPLASM THAT MAY BE GRANULAR OR CLEAR. TH E
EPITHELIAL CELLS ARE ORGA NISED IN TRABECULAE, RIBBONS OR
ROSETTES.
II) MESENCHYMAL COMPONENT INCLUDES FIBROUS CONNEC - TIVE TISSUE,
CARTILAGE AND OSTEOID OF VARIABLE DEGREE OF MATURATION.
EXTRAMEDULLARY HAEMATO POIESIS IS A FREQUENT ACCOMPANIMENT

22. •SECONDARY HEPATICTUMOURS
METASTATIC TUMOURS IN THE LIVER ARE MORE COMMON THAN THE
PRIMARY HEPATIC TUMOURS. MOST FREQUENTLY, THEY ARE BLOODBORNE
METASTASES, IRRESPECTIVE OF WHETHER THE PRIMARY TUMOUR IS DRAINED
BY PORTAL VEIN OR SYSTEMIC VEINS. MOST FREQUENT PRIMARY TUMOURS
METASTASISING TO THE LIVER, IN DESCENDING ORDER OF FREQUENCY, ARE
THOSE OF STOMACH, BREAST, LUNGS, COLON, OESOPHAGUS, PANCREAS,
MALIG NANT MELANOMA AND HAEMATOPOIETIC MALIGNANCIES.
SARCOMAS RARELY METASTASISED TO THE LIVER
MOST METASTATIC CARCINOMAS FORM MULTIPLE, SPHERICAL, NODULAR
MASSES WHICH ARE OF VARIABLE SIZE. LIVER IS ENLARGED AND HEAVY,
WEIGHING 5 KG OR MORE. THE TUMOUR DEPOSITS ARE WHITE,
WELLDEMARCATED, SOFT OR HAEMORRHAGIC. THE SURFACE OF THE LIVER
SHOWS CHARACTERISTIC UMBILICATION DUE TO CENTRAL NECROSIS OF
NODULAR MASSES
THE METASTATIC TUMOURS GENERALLY REPRODUCE THE STRUCTURE OF THE
PRIMARY LESIONS

24. THANK YOU!!!!