CLUTHA LTD v RISBY SUPREME COURT OF NEW SOUTH WALES COURT OF APPEAL CLARKE, COLE JJA and HUNTER AJA 4 March, 26 March 1996 [1996] NSWCA 106 Workers compensation — Whether relationship between injury and tumour — conflicting expert medical evidence — reasons for judgment — trial judge to sufficiently expose reasons for decision. In 1991, whilst working for the appellant (Clutha Ltd), the respondent (Vincent Risby) suffered an injury to his groin. He wa& able to return to work after treatment, but some months later the discomfort recurred. A lump was discovered in his groin which, after surgical removal, was found to be a rare form of cancer known as sarcoma. The worker then made a claim under the Worker's Compensation Act 1987 on the basis that the tumour was caused by the groin injury in 1991. Moroney CCJ was satisfied that the relationship between the tumour and the injury propounded by the worker's expert existed and thus upheld the claim. The employer appealed on the basis that on the evidence it was not open to the trial judge to make an affirmative finding on the probabilities that the sarcoma was attributable to the injury, and that the trial judge should have concluded the worker had failed to make out its case. It was also submitted that the trial judge had not given adequate reasons for his conclusion. The Court upheld the appeal but declined to decide the case as on a rehearing. Held: (1) A judge is bound to expose his or her reasoning process in sufficient detail to enable a losing party to understand why they lost. Where there were diametrically opposed views given by two eminent specialists, his Honour was bound to explain why he preferred the views of one specialist over the other: Soulemezis v Dudley (Holdings) Pty Ltd (1987) 10 NSWLR 247. (2) In circumstances where an eminent specialist has given an affirmative opinion, not diminished in any way in cross-examination, supporting a claim by a worker for compensation, the trial judge is not bound to reach a contrary conclusion. There was evidence capable of supporting the worker's case and it could not be said as a matter of law that the claim must fail. (3) Having not seen and heard the witnesses, the Court of Appeal was not in a position to decide the case as on a rehearing, and the matter should be remitted for a new trial in the Compensation Court: Ahmedi v Ahmedi (1991) 23 NSWLR 288, and Wilsher v Essex Area Health Authority [1988] AC 1074. Orders (1) The appeal be allowed. (2) The orders of Moroney CCJ be set aside. (3) The proceedings be remitted to the Compensation Court for determination. (4) The costs of the first trial to be in the discretion of the judge hearing the new trial. (5) The respondent pay the costs of the appeal and is to have a certificate under the Suitors Fund Act in respect of those costs. Clarke JA Vincent Risby ("the worker") was employed by Clutha Ltd ("the employer") in June 1991 as a miner at the employees Nattai South Colliery. On 17 June 1991 he experienced a tearing sensation in the right side of his groin while he was lifting a large piece of timber. Pain persisted in the area for several 2 UNREPORTED JUDGMENTS days but after physiotherapy the pain lessened and the worker returned to full duties on 5 July 1991. In September 1991 he noted some recurrence of discomfort in his right groin. Upon physical examination a medical practitioner noted that there was a lump in that area. There were then multiple visits to doctors. These continued throughout the latter part of 1991. Finally he was referred for a biopsy which suggested a tumour in the vicinity of the right groin. The worker was then referred to the care of Dr Shead for the surgical removal of the tumour and this was carried out on 27 March 1992. Following its removal the tumour was diagnosed as a "malignant fibro-sarcoma, high grade". The evidence disclosed that a sarcoma is a rare cancer of tissues and that it constitutes less than | per cent of all cases of cancer in New South Wales. Not only is a sarcoma rare but its appearance in the groin is itself rare. The worker made a claim under the Workers Compensation Act 1987 on the basis that the tumour was caused by the incident at work on 17 June 1991. His claim was heard by Moroney CCJ who upheld it and made awards on the basis of total incapacity and, later, partial incapacity. The employer has appealed from that decision and has made three discrete submissions: (1) On the evidence it was not open to the trial judge to make an affirmative finding on the probabilities that the sarcoma was attributable to the incident at work in June 1991; (2) On an examination on the whole of the evidence the trial judge should have reached the conclusion that the worker had failed to make out his case; and (3) The trial judge had not given reasons, or adequate reasons, for his conclusion. It is convenient first to deal with the third ground. His Honour, in his judgment, set out a great deal of evidence and then his conclusions which occupied the following two paragraphs: "The question seems to me to be this; does the applicant, with the support of Professor Kefford, establish his case of a relationship between the injury and the initiation in some manner or other of the malignant process of the point of probability, despite the evidence of Professor Tattersall. I feel that the applicant has discharged this onus. It is not a case where I am required to say I accept Professor Kefford and reject Professor Tattersall, or vice versa. Indeed, for me as a mere layman, it would be an arrogant impertinence. However, the situation is that I feel comfortably satisfied to find the relationship propounded by Professor Kefford whilst, at the same time, I say I respect the views of Professor Tattersall and say that he may well be correct. This is not an illogical thing to say. It is no more illogical than saying that I accept the views of Aquinas but acknowledge that the late Professor Anderson may well have been right. As a tribunal of fact, a jury, in effect, I am satisfied to find on the probabilities that the relationship has been shown in the manner advanced by Professor Kefford." In my opinion the employer is correct when it says that the trial judge failed to comply with his judicial obligation to provide adequate reasons. The nature of that obligation has been discussed in a number of cases but it is unnecessary for present purposes to go beyond the statements by Mahoney and McHugh JJA in Soulemezis v Dudley (Holdings) Pty Ltd (1987) 10 NSWLR 247 to the effect that the judge is bound to expose his or her reasoning process in sufficient detail to enable a losing party to understand why he or she had lost. URJ CLUTHA LTD v RISBY (Clarke JA) 3 It is true that the employer would realise that it had lost the case because his Honour was persuaded that Professor Kefford's view should be accepted. That is not sufficient, in my opinion, in the circumstances of this case. More was required, as McHugh JA explained in Soulemezis at 277, where there were diametrically opposed views given by two eminent medical specialists. His Honour was, in my opinion, bound to explain why it was that he preferred, as it seems he did, the views of Professor Kefford. In saying that I do not mean to suggest that an elaborate explanation was necessary. It was not. But his Honour was obliged, in my respectful opinion, to explain the factors which led him to accept the worker's case. In the two passages I have cited he did not do this. No more can be said than that he was satisfied on the probabilities. What led him to prefer Professor Kefford, and to find that the worker had discharged his onus, was left unexplained. Accordingly, the appellant has made good his third point. That conclusion is not sufficient to dispose of the appeal for it would lead to a new trial whereas a finding in favour of the appellant on the first ground would entitle it to an award in its favour. In these circumstances I tum to the first ground which involves the consideration of the competing views of Professor Kefford, who was called on behalf of the worker, and Professor Tattersall, who was called on behalf of the employer. The former, who acknowledged the rarity of the occurrence of a sarcoma in the groin, expressed the opinion that the continuity of symptoms since the suffering of the tearing sensation on 19 June 1991 in the precise area in which the tumour appeared provided a case upon which it could be said that one was probably linked with the other. He acknowledged that there were no known cases of sarcoma resulting from trauma but he thought that it was possible to argue that there was an analogy between trauma and surgical invasion and, insofar, as the literature indicated that a sarcoma could occur during the healing process after an operation it was reasonable to conclude that it could also occur from a traumatic injury. Professor Tattersall was adamant in his expression of the view that there was no link between the two. He said the time between the trauma and the development of the lump (3 months) was far too short and that the latency period for a sarcoma (that is the time that it takes to develop) was always greater than 12 months. He also denied that a sarcoma could result from operative treatment and thought the suggestion of a link between the incident at work and the development of the sarcoma was fanciful. Because the employer relied on Professor Tattersall it is convenient to refer, initially, to his opinion. That was expressed in summary form in these words: "In summary, I do not feel that there is any evidence that the tumour was caused by the injury, but rather feel that the groin strain - lifting injury may have occurred because of the pre-existing tumour and that as a result of the injury attention may have been drawn to the presence of the tumour earlier than might otherwise have occurred. I believe that the haematoma occurring as a result of a lifting injury in a damaged muscle may increase the risk of haematogenous spread of the tumour, but only time will tell whether this has taken place." In his evidence he said that there was no solid evidence establishing that a sarcoma is caused by trauma and he had not found in the literature any evidence to support the conclusion that sarcomas developed in surgical scars. In cross-examination it was put to him that if a person received a tear by way of surgical incision or by injury, the healing processes that developed were capable 4 UNREPORTED JUDGMENTS of producing cells that ultimately closed the wound but, because of a malfunction, continued producing cells which then became a tumour. His answer was in these terms: "T think its a hypothesis for which there is no substance from the experimental literature. It is clear that factors released by healing cells can accelerate the growth of pre existing cancer cells. There is no evidence from any literature that the application of those growth factors to normal cells will make them become malignant cells." Professor Kefford, on the other hand, thought the temporal relationship between injury and the onset of the mass pointed in favour of the link upon which the worker relied. In his report he had this to say about the relationship between the condition and previous trauma: "The temporal relationship between this man's injury and the onset of the mass in the groin with its associated symptoms, and the fact that there was no mass or symptoms prior to the injury must be taken as strong circumstantial evidence of a relationship between the severe groin injury and the development of a sarcoma in this unusual site. The iliacus muscle where the tumour had its origin which is precisely the muscle which would be expected to be injured or even tom in the type of injury described by the patient. Whilst there is no direct evidence from the medical literature of a relationship between trauma and sarcoma, this is a rare disease, and the site is particularly rare. Sarcomas have been shown to develop after other forms of tissue injury such as radiation therapy, although in this case a clear relationship can be seen to the specific DNA damage caused by the ionising radiation. Sarcomas have also developed in surgical scars, further evidence for relationship between tissue injury and the triggering of a malignant process. Whilst the possibility exists that the injury drew attention to a pre-existing mass, it would seem an extreme coincidence for this to happen, and furthermore, the rapid growth of the mass following the injury, is not consistent with a prior lesion which one would expect to have been causing symptoms before the injury. In summary I believe there is a strong likelihood of a relationship between this patient's injury and the initiation of the malignant process which finally manifested itself as a highly malignant tumour which is likely to severely limit his life expectancy. It should also be noted that trauma has been clearly shown to predisposed (sic) to the development of METASTATIC tumour. It is not outside the bounds of possibility that a patient may have circulating sarcoma cells which generally are killed by the immune system, having originated in another organ. However injury may predispose to the rapid growth of such cells in the site of injury. Furthermore, certain oncogenes have been shown to be activated in tissues following injury, so that there is also good circumstantial evidence from the laboratory to create a link between tissue injury and the development of malignancy." In his evidence in chief he said that the literature supported the proposition that sarcomas have developed in surgical scars. He likened surgical scars to tearing traumas and went on to explain the relationship between the healing process and the development of tumours. He said: "Q. what are those hypotheses? A. They relate to the close similarity between the healing process and the process of malignancy, and that is that malignancy is just a slight aberration of the normal cell division and proliferation of normal tissues that happens during healing, and if that process becomes slightly extended and slightly-aberrant, then a tumour forms. URJ CLUTHA LTD v RISBY (Clarke JA) 5 Q. You say 'slightly extended', what, do you mean the healing process continues after healing has been effected? A. Yes. Normally tissues divide until the two ends of a wound meet, and then the dividing cells stop dividing. Now, if they fail to stop dividing, then a tumour will form. Q. You have talked about surgical scars and the development of a sarcoma from surgical scars. There is no suggestion in this case, of course, that this man's tumour developed at the site of a surgical scar. Does your view of the development of tumours in the site of surgical scars in any way assist you with the hypothesis in this case? A. Yes, it does, because I think a tearing injury to a muscle is very little different to a clean wound made with a surgical knife. There's no difference in terms of wound healing, so the same hypotheses apply." Then, relying on the United States literature which had been published about three or four months prior to the hearing, he said: "A. Well, I think the most important recent evidence is at a basic molecular level, now that people are beginning to understand much better the very basis of malignancy at the genetic level, the genes which are turned on during the early stages of malignancy have been identified, and identical genes have now been identified to be switched on during wound healing, and this is, if you like, confirmation at the biochemical and molecular level of the hypotheses that were suggested to explain tumours forming in scars." In cross-examination the questioner fastened on to what he perceived to be the weakness in Professor Kefford's theory. Insofar as this part of the cross-examination was relied upon heavily by senior counsel for the employer it is desirable that I set it out. It reads: "Q. Statistically on the evidence available to you in your specialty so far, there has been no recorded cases of a latency period of less than 12 months? A. That's correct. Q. Statistically, there have been many cases of the development of sarcomas with no apparent cause? A. Correct. Q. Statistically, there have been far more sarcomas with no apparent cause than with a cause which could be related to trauma? A. Yes. Q. If in fact the first clinically detected signs of a lump were as soon as three or four months after the trauma, what I am putting to you is that although on the basis of the hypothesis to which you have referred, a relationship is still possible on the basis of the statistical information and investigations that have been done, you would not say that connection is probable, merely possible? A. I still can't say that, and I can explain, if you wish. Q. Certainly. A. The reason is that - you're referred with respect to statistics that are dreadfully flimsy, the numbers of events are so few in the literature that its impossible to make a scientific analysis and predict with a degree of statistical certainty, what is the latency period between trauma and the development of sarcoma. It's just not possible to do that. It's only possible to say that there is a relationship. Therefore, I'm neither persuaded nor dissuaded by the latency in this case. In other words, because there are so few events in the literature, the latency in this event would still fit within the likely range of possibilities that could occur, despite the fact that there have been none recorded so far that have had such a short latency. Is that clear, I am not... Q. Yes, yes, and in fact I think that was probably what I was putting to you, you are saying that there is a range of possible causes of sarcoma, ranging from the hypothesis of a causal connection between trauma and the development, does that summarise what you have just been saying? A. Well, no, I was really 6 UNREPORTED JUDGMENTS referring specifically to what is known about the relationship between trauma and sarcoma, and the latency question, and that is that there is insufficient evidence on which to say, you must have a latency period of more than 12 months if you are to describe a relationship. There is insufficient evidence. Q. Let me put this to you then; the evidence that is available so far in the literature, the latency period has always been in excess of 12 months? A. That's correct." The high point of the employer's case was that there was no known case In which the latency period of a sarcoma was less than 12 months. This was the main factor upon which Professor Tattersall relied but, of course, he also placed weight on the fact that there was no solid evidence that a sarcoma was caused following trauma or by surgery. Mr Gleeson QC, senior counsel for the employer, submitted that Professor Tattersall's opinion was soundly based whereas the opposing theory of Professor Kefford relied on hypotheses which were really no more than speculation. He pointed out that the theory postulated that sarcomas develop in surgical scars, that there is a true analogy between the healing process involved in those scars and the process involved in the healing of tearing injuries and, finally, he hypothesised that the short period of latency did not exclude the causal link in this case because of an insufficiency of evidence concerning latency. These factors rendered Professor Kefford's opinion highly speculative and one which could not stand against the opposing point of view. Counsel's high point was, of course, the known latency period. Counsel for the worker took a very different tack. He pointed out that the development of a sarcoma is a rare occurrence. That the development of a sarcoma in the groin is even rarer. This was a unique state of affairs and the consensus of medical opinion was that little is known about the development of sarcomas. In addition both the experts acknowledged the need to exercise care in expressing conclusions in the area. His case was that the court was concerned with a medical condition about which not very much was known and in which the doctors were bound to hypothesise. Where, as here, an oncologist of the experience and stature of Professor Kefford, who had seen an average of 400 cancer patients a year for 15 years, expressed the opinion that there was a strong likelihood of a relationship between the trauma and the development of the sarcoma, and in doing so relied partly upon a recent study of which Professor Tattersall seemed to be unaware, it was open to the trial judge to decide as a matter of judgment that it was more probable than not that the link for which the worker argued had been established. Furthermore, while there had been no instances of a latency period of less than 12 months demonstrated in the literature or in the experience of the two expert witnesses that could not be conclusive where an undoubted expert gave sound reasons for putting that factor to one side. In circumstances where an eminent specialist has given an affirmative opinion supporting a claim by a worker for compensation, which opinion was not diminished in any way in cross-examination, I am unable to accept that the trial judge was bound to reach a contrary conclusion. Certainly there was evidence capable of supporting the worker's case and it could not be said that, as a matter of law, the claim must fail. The criticisms concerning the latency period and the lack of solid support for Professor Kefford's evidence certainly demonstrated the need for careful analysis of the claim in the context of the evidence as a whole and particularly Professor Tattersall's evidence, but it does not mean that his Honour was bound to reject the claim. URJ CLUTHA LTD v RISBY (Hunter AJA) 7 The question which then arises is whether the Court should send the case back for a new trial or whether it is in a position to decide the case as on a rehearing, as it is invited to do by the employer's second submission. My initial disposition was to conclude that, the court not having seen and heard the witnesses, the matter should be remitted for a new trial in the Compensation Court. On further reflection my mind has vacillated but in the end I think my initial view is the better one. It is true to say that the case is a finely balanced one in which the court is required to weigh the competing opinions of eminent medical practitioners who are skilled in the particular area of medicine with which the case is concerned and that it is unlikely that demeanour would play any part in a decision to prefer the views of one to those of the other. Nonetheless, I consider that there are two considerations which require that the case be re-tried. The first is that the court has, in holding that the trial judge failed to give proper reasons, decided that the trial miscarried and that, in a real sense, the parties have not had a fair trial. Although new trials involve the parties in added delay and costs they are, in my opinion, the normal remedy for a mistrial. My second reason is that in the resolution of a question of fact the trial court is required to weigh the evidence given by the witnesses and, in doing so, has the undoubted benefit of seeing and hearing the witnesses give evidenced. Indeed this court has held, in Ahmedi v Ahmedi (1991) 23 NSWLR 288, that the principles whereby an appeal court is bound to accord appropriate weight to a trial judge's assessment of witnesses applies in the case of expert witnesses. In the course of my judgment in that case I cited from the speech of Lord Bridge in Wisher v Essex Area Health Authority [1988] AC 1074 where his Lordship said (at 1091): "... Where expert witnesses are radically at issue about complex technical questions within their own field and are examined and cross-examined at length about their conflicting theories, I believe that the judge's advantage in seeing them and hearing them is scarcely less important than when he has to resolve some conflict of primary fact between lay witnesses in purely mundane matters." In the circumstances of this case I consider that the parties are entitled to have the vexed question of causation resolved by a tribunal which has seen and heard the witnesses and which records its decision in a properly reasoned judgment. I would propose that: (1) The appeal be allowed. (2) The orders of Moroney CCJ be set aside; (3) The proceedings be remitted to the Compensation Court for determination. (4) The costs of the first trial to be in the discretion of the judge hearing the new trial. (5) The respondent pay the costs of the appeal and is to have a certificate under the Suitors Fund Act in respect of those costs. Cole JA I agree with Clarke JA. Hunter AJA I agree with Clarke JA. (1) The appeal be allowed. (2) The orders of Moroney CCJ be set aside. (3) The proceedings be remitted to the Compensation Court for determination. (4) The costs of the first trial to be in the discretion of the judge hearing the new trial. 8 UNREPORTED JUDGMENTS (5) The respondent pay the costs of the appeal and is to have a certificate under the Suitors Fund Act in respect of those costs. Counsel for the appellant: J Gleeson QC and A Hewitt Solicitors for the appellant: Sparke Helmore Counsel for the respondent: G Little Solicitors for the respondent: Maguire and McInerney