PULMONARY NEOPLASMS.

847 that it is useless when the haemoglobin reading is very do not bring out the fact that it is a constant feature of low. The various dilution methods (Sahli, Haldane, the condition ; they presumably refer to the clinical and so forth) are, as Dr. Jenkins points out, set to an diagnosis and not to the total incidence as revealed arbitrary and variable standard. I have, however, post mortem. Out of 29 post-mortems at the Royal found the Tallquist scale useful, provided that the Chest Hospital every case showed extensive pleural effect of tint (as opposed to tone) is excluded by making adhesions. In 13 there was also a large effusion of For this purpose a clear or cloudy fluid ; in 4 the fluid was haemorrhagic, the reading monochromatic. piece of pale green glass is sufficient. Both the in 5 it was purulent, and in 8 there was invasion of variations in the colour perception of different observers the pleura by new growth. I have not found that the large cell sometimes called and the differences in tint between old and fresh supplies of blood are thereby excluded. I have had "foulis " is pathognomonic of pulmonary tumour. before me three Tallquist scales of German, Italian, The same pale vacuolated cell is found in other forms of and alleged British origin respectively, which differ pleural effusion and it has no resemblance to the very much in colour, and there is evidently no malignant cells obtained if a pleural nodule is scraped. uniformity in this respect amongst the products of The only certain test of carcinoma in pleural fluid is different firms. When read through a green glass, the presence of columnar or spindle cells, and this is however, the difference is not sufficiently great to uncommon. Binucleate cells or plaques of endothelial invalidate the method for clinical purposes. cells forming rosettes indicate a lesion of the pleura The subject of haemoglobin values was discussed at not necessarily malignant, and are found in inflamlength in the proceedings of the weekly staff meetings matory conditions. A haemorrhagic fluid is very of the Mayo Clinic (Sept. 15th, 1926), when the Dare suggestive of carcinoma but occurs in only about a and dilution methods were controlled by spectrophoto- quarter of the cases and the diagnosis cannot depend metric determinations and by the Van Slyke oxygen upon its presence. I am, Sir, yours faithfully, capacity test. The variations disclosed were enormous. It is to be hoped that work on the lines of the Mayo NORAH H. SCHUSTER, M.B., Ch.B. Clinic procedure may result in the production of an Royal Chest Hospital, City-road, E.C., April 15th, 1929. accepted haemoglobin standard and an accurate method for its determination. Till then I submit that the Tallquist scale with a neutral tint reading is THE ÆTIOLOGY OF UROLITHIASIS. the best that can be employed in clinical practice. To the Editor of THE LANCET. I am, Sir, yours faithfully, A. KNYVETT GORDON. SIR,—Having read with interest Dr. Clifford Hoyle’s Bedford-square, W.C., April 15th, 1929. instructive article in your issue of April 6th (p. 734) I think his suggestion as to the aetiology of urolithiasis in tropical countries is based on a fallacy. It appears PULMONARY NEOPLASMS. to me that Europeans in the tropics suffer through over-protection from ultra-violet rays. Most of the To the Editor of THE LANCET. solar radiation is absorbed in the clothing, where it is SIR,—Dr. T. C. Hunt’s paper on this subject in your converted into heat and conducted to the body with last issue contains many points of interest, especially enervating effect, the skin beneath remaining absoconcerning the initial symptomatology and diagnosis lutely white. Fear of insolation leads to the covering of the primary carcinoma of the lung. of the head and shading of the face, so that the In an investigation of 62 cases particular attenof the Europeans have pale faces. Uromajority tion was paid to the clinical pathology of 29 which lithiasis in the tropics appears to me likely to be the came under observation at the Royal Chest Hospital, result of excessive sweating and therefore high and the findings seem to show that the negative concentration of the urine. In any case, when we results invariably reported in the literature are consider that two ounces of cholesterol contain only due to insufficiently thorough examination. Cough one grain of ergosterol it is hardly conceivable that a and pain are early and cardinal symptoms of the toxic dose of vitamin D could arise from the irradiation disease, and the sputum or pleural fluid (which is of the face and hands alone. cause of the first pain) is worth I am, Sir, yours faithfully, nearly always the investigation. Blood in the sputum is much more MURRAY LEVICK. G. G. MURRAY LEVICK. common than the text-books allow, but it may 929. Harley-street, W., April 15th, 1929. only occur intermittently or in small quantities, and is probably often omitted from hospital records. Specimens examined microscopically at the Royal ACTIVE IMMUNISATION AND DIPHTHERIA. Chest Hospital have been found to contain blood To the Editor of THE LANCET. which was invisible to the naked eye. At this hospital had 18 patients had haBmorrhagic sputum ; 5 little SIR,—Dr. Goodall expresses the opinion that the or no expectoration, leaving only 6 with no note of suspicious cases of " local diphtheria," referred to in bleeding. The presence of carcinoma cells is of some our paper, should have been counted as cases arising interest in clinching a clinical diagnosis. Very rarely in 1928 subsequent to prophylactic inoculation. His a fragment of growth is coughed up and available for letter is evidence that these cases should have been section. One patient here did this three times and included, since it was politic to avoid any " attempt on one occasion the piece was large enough nearly to to gloss over a failure." Our phrase " suggested a choke her. Isolated malignant cells are always difficult diagnosis " is admittedly unsatisfactory since, when to identify, but after having studied the sputum in a used by an expert of Dr. Goodall’s unrivalled experifew cases of pulmonary carcinoma, I think that with ence, it conveys a much higher probability that the " more experience they will be recognised more fre- patient is suffering from the clinical entity suggested." used someone than In the than when with heretofore. recent cases two the same amount quently by only examination of the sputum revealed carcinoma cells of experience as (say) myself. while the clinical diagnosis was still doubtful. The The subject of the diagnosis of these doubtful cases procedure is simple and takes no longer than looking is of great scientific interest, but much too lengthy to for tubercle bacilli in a series of specimens. Search discuss here. I hope my attitude with regard to them must be made on several occasions and at least two will be more intelligible when the full report of this portions of the same specimen examined. I simply Greenwich work is published. Dr. Goodall asks : make a wet preparation stained with thionin blue and Would these local cases, which were excluded from the examine at once. The observations are too few to 1928 diphtheria notifications, have been notified if enlarge at present on the nature of the cells and they had arisen in unimmunised boys ? Prior to 1922 the answer is, Yes. Since that date, as more and more naturally many controls are necessary. Dr. Hunt refers to the frequency of pleurisy as a confidence was gained in the reliability of the Schick complication of pulmonary tumours, but his figures test, both as a diagnostic and prognostic instrument,