On the basis of this study, which showed that certain diseases seem to be more 
prevalent in areas where there is compromised environmental quality, we decided to look 
at other more metabolically important tissues. Perhaps we would find other evidence of 
disease. 
One of the biomedical disciplines that we use very extensively at the Oxford 
Laboratory is an observational one called histopathology; however, it is not the only 
discipline of pathology. Histopathology can be very useful in the study of fish diseases, 
especially when other disciplines are poorly developed. We were intent on examining 
metabolic tissues such as the liver. I looked first at fish livers from Narragansett Bay 
and Long Island Sound. I found certain lesions which were significant and which were, as 
Leigh Bridges has said, identified as carcinomas (cancers). Then the opportunity to 
examine livers of winter flounder from Boston Harbor was provided. I did not pre-select 
Massachusetts with any malice in mind, but went there because winter flounder from the 
Harbor had fin rot. When I examined the liver tissues sent to me by DMF, I found the 
tumors I wish to present today. 
The resources made available to me for sampling Boston Harbor winter 
flounder are those of the DMF. As Leigh has mentioned, I have used the FC Wilbour at 
least five times. I was very fortunate to be able to trawl effectively; unfortunately, the 
boat is not adequate for doing much laboratory-oriented work. Trawl catches from Boston 
Harbor are essentially monotypic. When the cod end is opened and dumped on the deck, 
the catch is composed almost exclusively of winter flounder. I desperately wanted to find 
other fish from this area to examine; however, I could not because they were not present. 
Our laboratory table, at least on the first cruise, was quite rudimentary 
consisting of an abandoned boat hatch and a lobster pot. Mr. Vincent Durso, a staff 
member from DMF, assisted me as we necropsied fish at the naval shipyard in 
Charlestown. We laboriously examined fish after fish looking for gross lesions. 
Figure 4 illustrates a fish liver in which the functional cells of the liver, such 
as the hepatocytes, contain large vacuoles. Low magnifications of sections of liver with 
these highly vacuolated cells show that they cause the liver surface to bulge 
outwards. The gross appearance of the lesion, therefore, would be that of a tumor. 
This vacuolated cell was very common in livers of winter flounder from Boston 
Harbor. It was present in winter flounder from Narragansett Bay and Long Island Sound 
also, but never to the extent evident in Boston Harbor fish. On the basis of other cellular 
changes that were present, I began to think that the vacuolated cell was somehow part of 
the progression to neoplasia. 
Most of the guidance for naming these lesions is based on research done 
primarily with rodents by veterinary and human pathologists. For legal implications of 
what is found in studies of experimental carcinogenicity, the rat is the most acceptable 
surrogate. Terminology that is used to describe lesions in rats is the terminology used in 
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