A comparison of 111In with 52Fe and 99mTc-sulfur colloid for bone marrow scanning.

Under most circumstances 52Fe, 111In, and colloid show a similar distribution of marrow. The lesser uptake of 111In by liver and spleen may occasionally be of value in permitting visualization of that portion of the spinal marrow obscured by these organs in the colloid scan. However, in red cell aplasia, when there is dissociation between phagocytic and erythropoietic functions, scanning with 111In gives no information about erythropoietic tissue distribution. Therefore, indium cannot be used as an analog for iron in the study of the hematopoietic system.

The elution of 99-Tcm from red cells and its effect on red-cell volume measurement.

Technetium-labelled erythrocytes provide a satisfactory agent for the measurement of red-cell volume with the advantages that there is a low radiation dose and repeated measurements can be readily carried out. A method of labelling red cells using (99)Tc(m)O(4) (-) with a small amount of stannous chloride has been evaluated in 20 patients, and compared with measurements of red-cell volume with (51)Cr-labelled erythrocytes carried out simultaneously in the same subjects. No significant differences between the results by either method occurred if the period of observation was limited to 20 minutes after the injection of labelled cells. Thereafter, elution of Tc from the cells made the determination of red-cell volume with (99)Tc(m) less reliable. Accordingly, the use of (99)Tc(m) as the label for red-cell volume measurements will result in errors if mixing of the erythrocyte pool is delayed, unless an elution correction factor is applied.

Value of surface counting in predicting response to splenectomy in haemolytic anaemia.

The value of surface counting with (51)Cr-labelled red cells in predicting response to splenectomy in haemolytic anaemia has been analysed in 18 cases. The cases included six patients with congenital haemolytic anaemias, four with primary autoimmune haemolytic anaemias, and eight patients with secondary haemolytic anaemias (four with a positive antiglobulin test). All patients showed evidence of splenic accumulation of labelled cells and in 16 of the cases this was confined to the spleen. Improvement followed splenectomy in 17 of the cases although there was no close correlation between the magnitude of accumulation of radioactivity as measured by excess counts and the degree of response. The reasons for these discrepancies are discussed, The only patient who completely failed to respond to splenectomy had a sideroblastic element to the anaemia. It has been concluded that surface counting is of value in selecting patients for splenectomy but should not be depended upon without reference to other clinical and haematological factors, which are likely to influence the prognosis.

The treatment of mycosis fungoides and related conditions with particular emphasis on electron therapy.

The difficulties created by the lack of generally accepted views on classification, diagnostic criteria and natural history of the cutaneous lymphomata are discussed. Only the lymphomata which remain confined to the skin throughout the major part of their development are considered. It is emphasized that these are extremely radiosensitive and that there must be some factors as yet unknown which play a part in their unique natural history and response to treatment. The cutaneous lymphomata are considered under three headings: (1) lymphocytoma, (2) lymphosarcoma and reticulum cell sarcoma, (3) mycosis fungoides. The characteristics of the first two are discussed briefly and illustrative examples are given. The relatively benign nature of the lymphocytoma is stressed. It is suggested that the solitary lymphosarcoma of the skin should be treated by radical radiotherapy since long-term survival or cure may be achieved. The treatment of mycosis fungoides is considered in greater detail. The physical advantages of electron therapy are described and details given of whole body surface treatment with electrons produced by a 6 MeV linear accelerator and slowed down with carbon decelerators of appropriate thickness. The results in 73 patients treated by electrons are analysed. The early and late side-effects are mentioned and the necessity for investigating other forms of treatment is stressed. It is concluded that at the present time electron therapy is the most satisfactory form of treatment for mycosis fungoides.

Familial polycythaemia caused by a new haemoglobin variant: Hb Heathrow, beta 103 (G5) phenylalanine leads to leucine.

A new variant of haemoglobin A (Hb A) with a high affinity for oxygen has been found in an English family. Five members are affected and all are polycythaemic. This variant (Hb Heathrow) is the first of this class to be found in this country and has the same electrophoretic mobility as Hb A. It was discovered only by measuring the oxygen affinity of the patients' red cells. This emphasizes the need for measuring the oxygen affinity of haemoglobin in patients with polycythaemia if other clinical and haematological features associated with polycythaemia rubra vera are absent.

Quantitative measurement of splenic and hepatic red-cell destruction.

A method has been developed by means of which independent measurement can be made of the amount of red-cell destruction occurring in the spleen and the liver. The technique involves a standard red-cell survival study and surface-counting measurements together with quantitative scanning of the spleen and liver with 113mIn colloid in order to calibrate the surface counter. The rate of destruction in each organ is obtained by fitting the measured uptake curve for the organ to a theoretical uptake curve by computer. In addition, if whole body counting is also performed, the amount of red-cell destruction occurring in the rest of the reticuloendothelial system may be deduced. Results are given for measurements on a series of 11 patients.