the pathology of rectal tumoursi0i the pathology of rectal tumours by basil c. morson, m.a., d.m....

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I0I THE PATHOLOGY OF RECTAL TUMOURS By BASIL C. MORSON, M.A., D.M. Consultant Pathologist and Director of the Research Department, St. Mark's Hospital, London Epithelial Tumours Adenoma This is the commonest variety of rectal tumour. According to Helwig (I947) the incidence of adenomas increases with age. Approximately one person in five reaching the age of sixty has one or more tumours of the large intestine, most of these being found in the sigmoid colon and rectum. They are commoner in males than females in a proportion of about 3: 2. The age incidence is approximately the same as for car- cinoma, most of the tumours being detected in the sixth and seventh decades. They are frequently multiple. Adenomas vary in size from sessile, dome-shaped nodules a few millimetres in diameter up to nearly round, pedunculated tumours about i in. in diameter. They are rarely larger. Initially, all adenomas are sessile, but they become more pedunculated as they grow and as peristalsis attempts to propel them onwards with the intes- tinal contents. They also tend to become dark red as they enlarge, which is partly due to haemor- rhage within the tumour and partly to secondary infection with associated congestion of small blood vessels. The surface of a typical adenoma is lobulated with intercommunicating fissures or crevices between the lobules (Fig. i). In its histological structure the adenoma shows tubular overgrowth of the rectal epithelium. The epithelial cells vary from those seen in normal mucosa by a tendency to loss of mucus-secretion. They also have large vesicular nuclei and an in- creased number of mitoses. All stages of de- differentiation may be seen from an obviously benign appearance to active proliferation and structural irregularity amounting to pre-invasive carcinoma. Once invasion is seen within a polyp it is no longer an adenoma, but a carcinoma; but some reference to its origin from a previously benign tumour can be usefully made. Although it is now widely accepted that the rectal adenoma is a pre-cancerous lesion, it is useful to recall the evidence. In the first place, adenomas and carcinomas are found in the rectum with a similar frequency and have much the same AA A--1 FIG. i. Pedunculated adenoma of rectum about i in. diameter. age and sex inaidence. Moreover, in operation specimens of rectal cancer one or more simple adenomata are commonly found in the neighbour- hood of the primary tumour. Dukes (1926) described cases of rectal carcinoma in which there was histological evidence of an origin from a previously benign adenoma. Also, it is now a common experience for a clinically benign adenoma when examined histologically to show evidence of malignant change. Finally, it is established that patients with familial polyposis (adenomatosis) almost invariably develop car- cinoma if left untreated. copyright. on April 8, 2020 by guest. Protected by http://pmj.bmj.com/ Postgrad Med J: first published as 10.1136/pgmj.35.400.101 on 1 February 1959. Downloaded from

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Page 1: THE PATHOLOGY OF RECTAL TUMOURSI0I THE PATHOLOGY OF RECTAL TUMOURS By BASIL C. MORSON, M.A., D.M. Consultant Pathologist andDirector ofthe Research Department, St. Mark'sHospital,

I0I

THE PATHOLOGY OF RECTAL TUMOURSBy BASIL C. MORSON, M.A., D.M.

Consultant Pathologist and Director of the Research Department, St. Mark's Hospital, London

Epithelial TumoursAdenoma

This is the commonest variety of rectal tumour.According to Helwig (I947) the incidence ofadenomas increases with age. Approximatelyone person in five reaching the age of sixty hasone or more tumours of the large intestine, mostof these being found in the sigmoid colon andrectum. They are commoner in males thanfemales in a proportion of about 3: 2. The ageincidence is approximately the same as for car-cinoma, most of the tumours being detected in thesixth and seventh decades. They are frequentlymultiple.Adenomas vary in size from sessile, dome-shaped

nodules a few millimetres in diameter up to nearlyround, pedunculated tumours about i in. indiameter. They are rarely larger. Initially, alladenomas are sessile, but they become morepedunculated as they grow and as peristalsisattempts to propel them onwards with the intes-tinal contents. They also tend to become darkred as they enlarge, which is partly due to haemor-rhage within the tumour and partly to secondaryinfection with associated congestion of small bloodvessels. The surface of a typical adenoma islobulated with intercommunicating fissures orcrevices between the lobules (Fig. i).

In its histological structure the adenoma showstubular overgrowth of the rectal epithelium. Theepithelial cells vary from those seen in normalmucosa by a tendency to loss of mucus-secretion.They also have large vesicular nuclei and an in-creased number of mitoses. All stages of de-differentiation may be seen from an obviouslybenign appearance to active proliferation andstructural irregularity amounting to pre-invasivecarcinoma. Once invasion is seen within a polypit is no longer an adenoma, but a carcinoma; butsome reference to its origin from a previouslybenign tumour can be usefully made.Although it is now widely accepted that the

rectal adenoma is a pre-cancerous lesion, it isuseful to recall the evidence. In the first place,adenomas and carcinomas are found in the rectumwith a similar frequency and have much the same

AA

A--1

FIG. i. Pedunculated adenoma of rectum about i in.diameter.

age and sex inaidence. Moreover, in operationspecimens of rectal cancer one or more simpleadenomata are commonly found in the neighbour-hood of the primary tumour. Dukes (1926)described cases of rectal carcinoma in which therewas histological evidence of an origin from apreviously benign adenoma. Also, it is now acommon experience for a clinically benignadenoma when examined histologically to showevidence of malignant change. Finally, it isestablished that patients with familial polyposis(adenomatosis) almost invariably develop car-cinoma if left untreated.

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Page 2: THE PATHOLOGY OF RECTAL TUMOURSI0I THE PATHOLOGY OF RECTAL TUMOURS By BASIL C. MORSON, M.A., D.M. Consultant Pathologist andDirector ofthe Research Department, St. Mark'sHospital,

to- POSTGRADUATE MEDICAL JOURNAL February I959

FIG. 2.-Villous papilloma of rectum about 2z in.diameter.

Villous PapillomaThis tumour is much less common than the

adenoma. Swinton and Doane (I952) in a reviewof 300 patients with benign epithelial polyps of thelarge intestine found that 20 (6.6 per cent.) werevillous papillomas, most of them being found inthe rectum. They are about equally distributedbetween the sexes, most of the tumours beingdetected in the sixth and seventh decades.The differences between a typical adenoma and a

typical villous papilloma are striking both in theirpathology and behaviour. However, there aretumours which contain features of both types.'rhis mixed group is not a very large one, but itaccounts for difficulties in the differential diagnosisbetween an adenoma and a villous papilloma.The villous papilloma (Fig. 2) iS usually larger

than the adenoma when first seen. Often it is verylarge, reaching 4 or 5 in. in diameter. It is alwayssessile, although the centre of the tumour is raisedabove the surface of the surrounding normalmucosa to a greater extent than at its periphery.The surface of the tumour has a convoluted ap-pearance and is covered by delicate villous pro-cesses which make it soft and velvety to the touch.The villous papilloma is usually solitary. Micro-scopically it is composed of tall mucus-secretingcolumnar cells covering delicate, elongated villi.The amount of mucus secretion, particularly froma large tumour, may be enormous. Mucus is richin potassium and cases have been reported ofvillous papillomas associated with severe potassiumdeficiency (Starr et al., 1956).

The fact that villous papillomas may be verylarge, yet benign, does not mean that they are anyless prone to malignant change than the simple-adenoma. Their size is only a reflection of theirmode of origin. Whereas the adenoma arises froma relatively small circumscribed area of mucosa, thevillous papilloma usually has a wide field of origin.This makes the detection of early malignant changea difficult problem for both the clinician and thepathologist. The softness and mobility of a villous.papilloma may give a false impression on rectalexamination, and even multiple biopsies may notbe representative of the whole tumour. Some-times, complete local excision is necessary beforemalignant change can be excluded.

Reference has been made above to the excessivesecretion of mucus by villous papillomas. Thischaracteristic is passed on when they becomemalignant. In the St. Mark's series of villouspapillomas showing malignant change, about athird of the carcinomas are of the mucus-secretingor colloid variety. This is three times the in-cidence of mucus-secreting carcinomas in thegeneral series of St. Mark's cases.

Familial PolyposisThis is an hereditary disease in which the colon

and rectum are covered by large numbers ofadenomata of different sizes and at different stagesof development. Polyposis is transmitted by adominant gene, the affected parent passing it onto approximately half of his or her children. AtSt. Mark's Hospital research into familial poly-posis has been carried on for the past 30 years. Thepathology of the disease in I56 patients from 4Ifamilies has been described by Dukes (1952). Theadenomata of familial polyposis develop in post-natal life, the average age of onset of symptomsbeing about 20 years, but it is rare for the firstsymptoms to occur before the age of ten or afterthe age of forty. Carcinoma of the colon or rectumis almost certain to develop in a patient withfamilial polyposis, the average age of onset beingabout 35 years compared with an average age of6o yearr for patients with non-familial carcinoma.

Congenital PolypsThere are two rare varieties of rectal polyp with

which the simple adenoma may be confused.Firstly, there is the congenital mucous polyp. Thisis not a neoplasm but a hamartoma, and is there-fore not a pre-cancerous lesion. It is composedof rectal tubules lined by well-differentiated mucus-secreting epithelium lying in a stroma of connec-tive tissue which resembles primitive mesenchymein its histological structure. The tubules tend tobecome dilated with excess mucus secretion, and

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Page 3: THE PATHOLOGY OF RECTAL TUMOURSI0I THE PATHOLOGY OF RECTAL TUMOURS By BASIL C. MORSON, M.A., D.M. Consultant Pathologist andDirector ofthe Research Department, St. Mark'sHospital,

February 1959 MORSON: The Pathology of Rectal Tumnors 103

the cut surface of the polyp may be obviouslycystic. Furthermore, the amount of stroma ismuch greater than in a simple adenoma. Thiscongenital polyp may be multiple, and is a rarecause of bleeding in children and young adults.A second rare type of rectal polyp is found in the

Peutz-Jeghers syndrome. This syndrome consistsof muco-cutaneous pigmentation associated. withgastro-intestinal polyposis (Dormandy, 1958), al-though a minority of patients have rectal tumours.In their histological structure the Peutz-Jegherspolyps show normal intestinal epithelium coveringbranching bands of smooth muscle. The relation-ship of the epithelium to the smooth muscle is thesame as that between the epithelium and themuscularis mucosa in normal mucous membrane.There is no abnormal epithelial proliferation andthe appearances are those of a hamartoma and nota true neoplasm. It follows that the Peutz-Jeghers polyp is not a pre-cancerous lesion.

CarcinomaRectal carcinoma is one of the commoner forms

of malignant disease. There are about 5,500deaths per annum in England and Wales, which is6 per cent. of all forms of cancer, the average ageat death being 69 years (Registrar General, 1956).At St. Mark's Hospital the average age of patientswith rectal cancer at the time of diagnosis is about6o years and the sex incidence about 2: i in favourof males.Age is important in the study of the natural

history of rectal cancer. Thus, the incidence oflymphatic metastases in patients under 40 years ofage is over 70 per cent., and falls to only about40 per cent. in the eighth decade. Furthermore,the study of the relationship between age andhistological grade shows that the average age ofpatients with low-grade carcinoma is greater thanthe average age of those with high-grade carcinoma.

Rectal carcinoma presents either as an ulceratingor as a protuberant tumour. It occurs with equalfrequency in the upper, middle and lower thirdsof the rectum. Furthermore, there is no differencein the pathological features, such as grade ofmalignancy and extent of spread, at the three sites.It is not surprising, therefore, that the prognosisat the different levels of the rectum after radicalsurgical treatment is very similar.About 5 per cent. of patients with rectal cancer

develop more than one growth of the large intes-tine. However, the incidence of multiple malig-nancy is much higher in patients with carcinomafollowing familial polyposis and ulcerative colitis.About 87 per cent. of rectal carcinomas are

adenocarcinomas of varying degrees of differentia-tion. A further IO per cent. approximately aremucus-secreting adenocarcinomas, so-called be-

cause they contain substantial quantities of mucus.The remaining 3 per cent. includes purely anaplas-tic tumours (carcinoma simplex) and signet-ringcell carcinoma which is really anaplastic mucus-secreting carcinoma. For many years it has beencustomary at St. Mark's Hospital to divide rectalcarcinoma into three histological grades of malig-nancy-low, average and high. About 20 per cent.are a low grade of malignancy, 50 per cent.average and 30 per cent. high grade. That this isa valid means of assessing the approximate rate ofgrowth of rectal carcinoma is shown by comparingthe grade of malignancy with the extent of spreadin operation specimens. Whereas the incidenceof lymphatic metastases is only 25 per cent. in low-grade carcinoma,, it is about 50 per cent. in averagegrade, and nearly 8o per cent. in high-grade car-cinoma. Moreover, Dukes and Bussey (1958) haveshown that the histological grade of malignancyinfluences the survival rate of patients with rectalcarcinoma. The corrected five-year survival ratefor patients with low-grade tumours is nearly 8oper cent., for those of average grade about 6o percent. and for high-grade malignancy only 29per cent. The five-year survival rate for purelyanaplastic carcinoma and for signet-ring celltumours is worse still.The A, B, C, or Dukes Classification of rectal

carcinoma is based on the extent of spread inoperation specimens. It has proved to be a con-venient method of relating pathology and prog-nosis. Dukes and Bussey (1958) have recentlygiven an account of the extent of spread of rectalcancer and its effect on prognosis in a large seriesof cases. The corrected five-year survival rate ofA cases (growth limited to the rectum with noextra-rectal spread or lymphatic metastases) is97.7 per cent. The five-year survival of B cases(spread by direct continuity into extra-rectaltissues without lymphatic metastases is 77.6 percent., and for C cases (lymphatic metastasespresent) is 32 per cent. The importance ofobservations on lymphatic spread can be seen bycomparing the survival of B and C cases.Most patients with rectal cancer die from

secondary deposits, usually in the liver, but also inthe lungs, brain and bones. It is justifiable topresume that these secondary deposits are usuallythe result of metastases via the veins draining theregion of the primary growth. In operationspecimens it is sometimes possible to detect venousspread in the form of a solid cord of growth grow-ing along the lumen of a vein in direct continuitywith the primary tumour. This is known asvisible venous spread, and must be distinguishedfrom microscopic venous spread which cannot bedetected by careful dissection. Visible venousspread has been detected in i i per cent. of I,795

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Page 4: THE PATHOLOGY OF RECTAL TUMOURSI0I THE PATHOLOGY OF RECTAL TUMOURS By BASIL C. MORSON, M.A., D.M. Consultant Pathologist andDirector ofthe Research Department, St. Mark'sHospital,

104 POSTGRADUATE MEDICAL JOURNAL February 1959

consecutive operation specimens at St. Mark'sHospital. The discovery of this form of spread ofrectal cancer in an operation specimen worsens theprognosis only slightly (Dukes and Bussey, I958).Venous spread in rectal cancer may also be

detected in histological sections of the primarytumour and by the cytological demonstration oftumour cells in blood taken from the superiorhaemorrhoidal vein. By these methods it ispossible to detect venous spread in a high propor-tion of cases.An account has already been given of the pre-

cancerous nature of benign epithelial tumours ofthe rectum and familial polyposis. Another diseasewhich is prone to the development of carcinoma ischronic ulcerative colitis. The incidence of cancerfollowing colitis varies with the severity and dura-tion of the disease. Weckesser and Chinn (I953)found the average duration of symptoms of ulcera-tive colitis prior to the development of cancer tobe about io years. At St. Mark's Hospital theincidence of cancer of the colon or rectum inoperatior specimens is about 5 per cent.The pathology of carcinoma arising in a patient

with colitis is characteristic. Firstly, the tumoursare often multiple. Secondly, they are flat andinfiltrating, with an ill-defined edge resemblinglinitis plastica of the stomach. Lastly, most ofthem are mucus-secreting carcinomas of a high-grade malignancy, often showing signet-ring cellformation. Generally the prognosis is poor.

CarcinoidThis is an uncommon type of rectal tumour. It

presents as a small, hard submucosal nodule aboutI cm. diameter and is usually found accidentally.It may be mistaken for an adenoma or a carcinoma.The diagnosis is made by biopsy which shows atumour composed of small cells containing nucleiwhich are very regular in size and shape and con-tain few mitoses. The cells are arranged in solidclumps which resemble those seen in the ileo-caecal type of carcinoid, but there are also areaswith an adenomatous pattern, and others showribbon-like festoons of columnar cells as describedby Stout (I942). Infiltration of the surroundingtissues is always present, but the cytoplasmicgranules characteristic of the ileo-caecal type ofcarcinoid are seldom seen (Morson, 1958).

This small submucosal variety of rectal car-cinoid is a very slowly growing malignant tumour,which is most unlikely to develop metastases.Experience at St. Mark's Hospital suggests thatlocal excision is adequate treatment. However, ifa carcinoid is greater than i cm. diameter andshows ulceration, metastases may have occurredand a radical operation is necessary. Such a casehas been reported by Gabriel and Morson (1956).

Histologically, this showed a degree of anaplasianot seen in the small submucosal variety of car-cinoid. The patient had liver deposits at the timeof operation and died three years later.No case has yet been reported of a carcinoid of

the rectum with the clinical syndrome of cu-taneous flushing, diarrhoea and pulmonary stenosisdue to excessive secretion of 5-hydroxytryptamine(5-H.T.). Moreover, urine tests performed oncases of rectal carcinoid at St. Mark's Hospitalhave never shown any excess of urinary 5-hydroxy-indole acetic acid, the excretion product of 5-H.T.This is probably explained by the lack of cyto-plasmic granularity in rectal carcinoids, for it isbelieved that these granules are the morphologicalbasis of 5-H.T. production.

Tumours ofLymphoid TissueLymphoma

In the rectum the term lymphoma is used todescribe a relatively small submucous tumourwhich is quite benign in its behaviour. It appearsto have no relationship to lymphosarcoma. It isan uncommon tumour, and only 87 cases havebeen seen at St. Mark's Hospital in the last 28years. It is commoner in men than women andthe average age of patients at the time of diagnosisis 36 years. Over 6o per cent. of all lymphomasare found in the third and fourth decades of life.

Rectal lymphoma presents as a round, smoothnodule, which is entirely submucous in position.It is firm in consistency, and is rarely more thani in. diameter. Most of the tumours are found inthe lower third of the rectum and just above themuco-cutaneous junction of the anal canal. Theymay be multiple. An analysis of the St. Mark'scases shows that 8o per cent. of the tumours werefound incidentally during rectal examination forother conditions, mainly of an inflammatorynature. This observation, taken in conjunctionwith the low average age of patients with rectallymphoma, suggests that it is an inflammatoryrather than a neoplastic condition. Furthermore,a' follow-up ' of the St. Mark's cases has revealedno evidence of recurrence and no subsequenthistory of lymphosarcoma.Lymphoma arises as a result of hyperplasia of

the rectal lymphoid follicles. The tumours arecomposed of well-differentiated lymphoid tissueshowing follicle formation and covered by at-tenuated mucous membrane. The appearanceresembles a lymph node, but without any lymphsinuses or capsule. There is no evidence of activeinflammation, no increase in the number ofmitotic figures or other evidence of neoplasia.

LymphosarcomaThis is a very rare form of rectal malignancy

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Page 5: THE PATHOLOGY OF RECTAL TUMOURSI0I THE PATHOLOGY OF RECTAL TUMOURS By BASIL C. MORSON, M.A., D.M. Consultant Pathologist andDirector ofthe Research Department, St. Mark'sHospital,

February 1959 MORSON: The Pathology of Rectal Tumours 105

which presents either as a solitary rectal ulcer or asgeneralized disease of the lymphoid follicles of therectum and colon.The lymphosarcomatous ulcer of the rectum

does not differ from carcinoma in its gross ap-pearance, and the diagnosis of a tumour of lym-phoid tissue is made by biopsy. The histologicalappearances have to be distinguished from benignlymphoma in particular and this may be extremelydifficult, especially if the lymphosarcoma is well-differentiated. However, the presence of a tumourgreater than i in. diameter which is also ulceratingthrough the rectal mucosa supports the diagnosisof malignancy. Further, a search should be madefor enlarged lymph glands elsewhere in the bodyand one removed for confirmation of the diagnosis.

Generalized lymphosarcomatous disease of thelymphoid follicles of the rectum and colon presentsas a diffuse intestinal polyposis which must bedistinguished clinically from familial adenomatosis.The polyps in this diffuse form of lymphosarcomaare composed of proliferating lymphoid tissuecovered by attenuated mucosa. They are roundedtumours which become pedunculated as they growlarger. There may be an associated lymphaticleukaemia.

Reticulum Cell SarcomaOnly three cases have been studied at St. Mark's

Hospital in the last 30 years. They were verylarge tumours involving most of the rectum andspreading widely into the peri-rectal tissues andlymph glands. The prognosis is very poor.

Tumours of Smooth MuscleLeiomyoma

Only three examples of this benign tumour havebeen recorded at St. Mark's Hospital. They weresmall, hard submucous nodules. Microscopicallythey contained well-differentiated smooth musclefibres and appeared to be arising from the mus-cularis mucosae. Leiomyoma arising within themuscularis externa has also been described.

LeiomyosarcomaThis is another rare form of rectal malignancy

which arises from the smooth muscle in the rectalwall. Typically, it presents as a nodular, pro-tuberant swelling which is partly covered by intactmucosa, but shows central ulceration. It can bedistinguished from carcinoma because it obviouslyarises from the deep tissues of the rectal wall.Microscopically, the tumours are composed ofinterlacing bands of smooth muscle fibres whichare mostly well-differentiated and of a low gradeof malignancy. They spread principally by directextension into the peri-rectal fat and by the veins,giving rise to metastases in the liver aid lungs.

Lymphatic spread is only found in the veryanaplastic forms of leiomyosarcoma. A study ofthe St. Mark's cases suggests that the ultimateprognosis is poor, the patients dying from localrecurrence and secondary deposits in the liver andlungs. However, most cases of rectal leiomyosar-coma are of a relatively low grade of malignancyand more than half the patients have survivedfive years.

Miscellaneous Rare TumoursHaemangioma

Cavernous haemangioma may be either cir-cumscribed or diffuse (Gabriel, 1945). It involvesprincipally the sub-mucosa of the rectum, appear-ing as a collection of dark red lobular swellingscovered by attenuated mucous membrane. Thelesion may involve the whole of the rectum, extend-ing into the anal canal and up the sigmoid colon.In these diffuse cases the blood vessels in theperirectal fat and sigmoid mesentery may alsoshow angiomatous changes. The condition isreally a congenital abnormality and there is noneoplastic proliferation. However, because ofsecondary haemorrhage and technical difficultiesin the surgical treatment, the prognosis of thediffuse cases of rectal angioma is poor.

LipomaSubmucous lipoma of the rectum has been

described, but is extremely rare. It presents as apedunculated tumour, prolapsing out of the anus.It is covered by intact mucosa and the cut surfaceshows yellow fatty tissue.

EndometriomaThis tumour is, of course, not a neoplasm, but

its inclusion in any classification of rectal tumoursis justified because it presents as a hard mass in therectum and may be confused with carcinoma. Thehistological appearances in the rectal biopsy of anendometrioma may also be difficult to interpret.The tumour is submucous in position and coveredby intact mucous membrane. Its cut surfaceshows localized smooth muscle hypertrophyaround small, blood-filled cysts.

Secondary Tumours of the RectumAny growth which spreads into the pouch of

Douglas or recto-vesical pouch may ulcerate intothe rectum. This is not uncommon in carcinomaof the pelvic colon which may prolapse into therecto-vesical pouch with secondary ulcerationthrough the rectal wall. Secondary involvementof the rectum may also occur in this way withcarcinoma of the bladder and ovary. Cervicalcancer may spread through the rectal wall, butthis happens only at an advanced stage of thedisease.

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xo6 POSTGRADUATE MEDICAL JOURNAL February I959

Despite the close anatomical relationship be-tween the rectum and the prostate it is uncommonfor prostatic cancer to invade the rectal wall,except in advanced disease. It is probable that thefascia of Denonvilliers provides an effective barrierto the backward spread of prostatic cancer. Onrectal examination it presents either as an anteriorsubmucous mass, a tubular stricture or, rarely, asa rectal ulcer. The diagnosis may be suspectedclinically, and is confirmed by rectal biopsy andpossibly a raised level of serum acid phosphatase.In view of the differences in treatment it is ob-viously important to distinguish between primaryrectal cancer and secondary invasion of the rectalwall by prostatic carcinoma.Squamous cell carcinoma, arising from the

upper part of the anal canal, may spread upwardsinto the rectum and present as a primary rectaltumour. The examination of biopsy material willdistinguish it from adenocarcinoma. Another typeof anal malignancy which shows preferential localspread upwards into the rectum is the rare malig-nant melanoma which always arises from the

upper part of the squamous-lined portion of theanal canal. It usually presents more as a rectalthan an anal tumour, but its onrgin from thesquamous epithelium of the anal canal cannot bedisputed, and it is, therefore, classified withtumours of the anus.

BIBLIOGRAPHYDUKES, C. E. (I926), Brit. J. Surg., 13, 720.DUKES, C. E. (I952), Ann. Eugen. (Camb.), 17, I.DUKES, C. E., and BUSSEY, H. J. R. (I958), BEt. Y. Cancer. In

Press.DORMANDY, T. L. (I958), 'Modem Trends in Gastro-

enterology,' Second Series. Edited by F. Avery Jones.GABRIEL, W. B. (I945), 'The Principles and Practice of Rectal

Surgery,' Third Edition.GABRIEL, W. B., and MORSON, B. C. (1956), Proc. roy. Soc.

Med., 49, 472.HELWIG, E. B. (I947), Surg. Gynec. Obstet., 84, 36.MORSON, B. C. (I958), 'Modem Trends in Gastro-enterology,'

Second Series. Edited by F. Avery Jones.REGISTRAR-GENERAL (1956), 'Statistical Review of England

and Wales.'STARR, A., MUELLER, S., and McKITTRICK, J. R. (I956),

Arch. Surg. (Chicago), 73, 995.STOUT, A. P. (1942), Amer. J. Path., 18, 993.SWINTON, N. W., and DOANE, W. A. (1952), Surg. Clin. N.

Amer., 32, 923.WECKESSER, E. C., and CHIN, A. B. (I9S3), J. Amer. med. Ass.'

152, 905.

0

vleW44

CLINICAL BIOCHEMICAL METHODSBy A. L. TARNOKY. PP. 239, figs. ii. London:

Hilger & Watts Ltd. 50s.This well-produced volume is a bench book

intended primarily for the biochemical technician.Instructions are clearly given, with a mininum ofexplanation and no interpretation. There are threepages of references and both an author and asubject index. The methods are those used in theauthor's laboratory in the Royal Berkshire Hos-pital; this means that they are well tried and thatthe author can vouch for their reliability, but itsomewhat restricts his range. None is included forthe estimation of iron, for instance. The use ofthe manometric Van Slyke apparatus is describedfor estimation of the alkali reserve (sic); it is sur-prising to find this included with a method forplasma pH which employs the Lovibond com-parator. The book also presupposes that a Hilgerabsorptiometer will be used; surely it would bemore in keeping with such an instrument to recom-mend the construction of standard curves ? Thisomission is surprising in view of the inclusion of ashort but useful chapter on analytical error.A chapter on the choice and care of laboratory

glassware would be useful. The book is veryclearly printed and set out, with a large page andample margins; it might have been helpful to haveblank pages at intervals for notes.

EMERGENCY SURGERYBy HAMILTON BAILEY, F.R.C.S., F.R.S.E. Seventh

Edition. Pp. I 21 3, with 1576 illustrations. Bristol:John Wright and Sons Ltd. 1958. g9 9S. od.The appearance of the first completely revised

edition since the last war of this surgeon's vade-mecum is indeed a great event. The publishers areto be congratulated on the very high standard ofthe production, and Mr. Bailey's long hours of toilare amply rewarded.Many chapters have been completely rewritten

and numerous excellent illustrations (monochromeand colour) have been added. In this book we canobtain all the practical advice culled from writingsand sayings of surgeons the world over, and thereferences are there at the end of the chapter foreasy access.

In the appendix at the end one will find most ofthe useful tips and tricks which have been publishedsince 1955.The volume sets out to be a reliable reference for

the surgeon who is called upon to do emergencysurgery.. It achieves much more than this, forbetween its covers can be found the lore of thepractical surgeon in any of the branches of surgery.

Certainly the young surgeon requires this text-book on his desk-not on his shelf. The oldersurgeon can spend many profitable hours browsingthrough its pages. G.F.C.

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