Adjuvant VHF therapy in locally recurrent and primary unresectable rectal cancer.

In a prospective randomized study, 434 mHz microwave therapy combined with external beam radiotherapy (VHF + RT) was compared with standard external beam radiotherapy (RT) in controlling locally recurrent or unresectable primary adenocarcinoma of the rectum. Independent assessors documented quality of life scores, performance status, toxicities, local response to treatment, and systemic disease progression before treatment and after treatment and every 8 weeks thereafter. Of 75 patients randomized, 73 were eligible for inclusion in the study. Forty-three of these patients had local pelvic tumour recurrence only and 21 also had distant metastases. In addition, nine patients had primary inoperable carcinomas, two of whom also had metastases. Thirty-seven patients were randomized to RT and 36 to VHF + RT. The median dose of radiation in the VHF+RT arm was 4275 cGy with a median fraction size of 150 cGy and median duration of therapy of 48.5 days versus 4500 cGy in the RT-only arm with a median fraction size of 180 cGy and median duration of therapy of 38 days. These doses are unlikely to be significantly different in biological effect. No significant difference between the two groups was observed in extent and duration of local control, measures of toxicity or quality of life scores. Additionally, survival and cumulative incidence of pelvic site of first progression did not differ significantly between the groups. We conclude that VHF microwave therapy in conjunction with radiotherapy produces no therapeutic advantage over conventional radiation therapy alone in the treatment of locally recurrent rectal carcinoma.

Mesenchymal chondrosarcoma arising in fibrous dysplasia of the femur.

The occurrence of mesenchymal chondrosarcoma in an area of fibrous dysplasia in the upper femur of a 28 year old man is reported. It is believed that this is the first documented example of such an association. A further unusual feature is the presence of benign giant cells in the mesenchymal chondrosarcomatous component.

Operation for non-union of stress fracture of the tarsal navicular.

Stress fractures of the tarsal navicular do not heal predictably with conservative treatment, so we recommend operation if the fracture remains symptomatic, and radiographs show wide separation of a complete fracture, extension of an incomplete fracture, delayed healing, or a medullary cyst. An autologous bone graft is inserted after en-bloc resection of the fracture surfaces. It is important that the fracture is fully exposed to its distal limits before the graft is inserted. We have grafted 19 fractures in 18 patients. Six fractures were complete, 12 incomplete and one had a residual medullary cyst. Of the 15 patients with adequate follow-up, 12 had been able to return to a pre-injury level of activity by five to 12 months.

Osteofibrous dysplasia of the tibia and fibula.

Osteofibrous dysplasia (ossifying fibroma of long bone) is an uncommon disorder of bone affecting the tibia and, rarely, the fibula of children and adolescents. It has been delineated from monostotic fibrous dysplasia, from which it can be distinguished by its radiological and histological characteristics and by its clinical course. We report 11 patients with osteofibrous dysplasia whose ages ranged from 10 months to 22 years. Four presented with a pathological fracture and in 2 a pseudarthrosis developed. A circumscribed area of intracortical lucency and expansion in the diaphysis is the characteristic radiological finding. Histologically there is a similarity to fibrous dysplasia but the trabeculae are lamellar or have a lamellar surface and most show osteoblastic rimming. Treatment may be difficult but more recent experience strongly favours a conservative approach wherever possible.

Melanoma in Western Australia in 1980-81: incidence and characteristics of histological types.

All cutaneous malignant melanomas diagnosed in Western Australia in 1980-81 were reviewed and classified according to histological type (i.e., superficial spreading melanoma, Hutchinson's melanotic freckle melanoma (lentigo maligna melanoma), nodular melanoma and melanoma of unclassifiable type). The most common invasive melanoma was superficial spreading melanoma with an incidence rate of 14.3 per 100,000 person-years in females and 9.0 in males. It most commonly affected the trunk in males and the lower limbs in females and showed a peak incidence in middle life. Invasive Hutchinson's melanotic freckle melanoma was much less common than invasive superficial spreading melanoma (1.8 per 100,000 person-years in both sexes), occurred most commonly on the head and neck and increased progressively in incidence with age. Nodular melanomas were more frequent in men (4.5 per 100,000 person-years) than women (2.0). They were thicker than other types of invasive melanomas, showed more mitotic activity and had less evidence of regression. Their site distribution was similar to that of superficial spreading melanoma. In women the pattern of incidence with age was also similar to that of superficial spreading melanoma. In men it was more like that of Hutchinson's melanotic freckle melanoma. Melanomas of unclassifiable type did not have distinctive epidemiological features common to both sexes, although the trunk was the site most commonly affected in both men and women. With some exceptions the patterns of occurrence of in-situ lesions were similar to those of the corresponding invasive lesions. Benign melanocytic naevi were found less often in association with Hutchinson's melanotic freckle (melanoma) (6%) and nodular melanoma (9%) than with superficial spreading melanoma (22%) or melanoma of unclassifiable type (34%).

Melanoma in Western Australia 1975-76 to 1980-81: trends in demographic and pathological characteristics.

Trends in incidence rates of cutaneous malignant melanoma in Western Australia from 1975-76 to 1980-1981 have been examined with reference to age, sex, body site, presence or absence of dermal invasion, tumour thickness, histological type, socioeconomic status and occupation. The incidence rates of all melanomas increased from 22.1 to 31.5 per 100,000 person-years in males and from 23.6 to 28.6 in females. In males, the relative annual increase in the incidence of invasive melanoma was 2.2%, and in females it was 5.6%. In-situ melanomas had larger relative increases in incidence (28% per annum in males and 10% in females) and the thickness of invasive lesions decreased between 1975-76 and 1980-81. The relative increase in incidence of invasive melanomas was greatest on the body sites with the highest rates initially--the trunk in males and the lower limbs in females. There was an increase in the proportion of invasive lesions classified as superficial spreading melanoma. The increase in incidence of in situ melanomas was largely restricted to the head and neck in older men of high socioeconomic status resident in Perth. This trend in in-situ melanoma was mainly due to an increase in the recorded incidence of Hutchinson's melanotic freckle. It may have been, in part, an artefact due to increased recognition of Hutchinson's melanotic freckle in this sub-group of the population.

Inter-observer variation between pathologists in the classification of cutaneous malignant melanoma in western Australia.

Inter-observer variation between six pathologists in their application of histological classifications during a survey of cutaneous malignant melanoma was analysed using kappa statistics. The highest levels of adjusted agreement were attained for tumour thickness and the presence of ulceration; intermediate levels were achieved on cross-sectional profile, level of invasion, histogenetic type, solar elastosis and the presence of an associated benign melanocytic lesion; agreement on other histological features of melanoma tended to be relatively poor. The problems experienced in the interpretation of these classifications are discussed and suggestions for their improvement are offered.

Inter-observer variation in the histopathological reporting of Hodgkin's disease: an analysis of diagnostic subcomponents using kappa statistics.

Levels of agreement between nine pathologists on the Rye classification of Hodgkin's disease and on diagnostic subcomponents used in applying the classification, were analysed by kappa statistics. Pathologists experienced comparatively little difficulty in agreeing on the presence of nodules and lacunar cells and hence best agreement was achieved on the nodular sclerosis category. Poorer agreement levels on the lymphocytic predominance, mixed cellularity and lymphocytic depletion categories were explained mainly by problems in the assessment of numbers of lymphocytes and abnormal reticulum cells other than Reed-Sternberg cells. Identification of the Reed-Sternberg cell, although of paramount importance to a diagnosis of Hodgkin's disease, appeared to have no great practical relevance to use of the Rye classification in this series of cases.

An improved method of analysis of observer variation between pathologists.

An improved method of analysing interobserver variation in histopathological studies is described and illustrated, by use of data from a congruence survey of malignant melanoma. The method provides, between any number of pathologists, an assessment of overall agreement and of agreement on each individual category of a classification system. Adjustment for differences in chance agreement due to varying numbers of categories or an altered composition of cases is included in the analysis. A generalization of the procedure designed to measure the strength of associations between different categories is formulated and explained with the use of an example.

The Rye classification of a population based series of Hodgkin's disease patients in Western Australia.

Data are presented on the incidence in Western Australia of subtypes of Hodgkin's disease which were obtained by review of all cases of the disease notified between 1960 and 1974. Observations were also made on within- and between-observer agreement on the use of the Rye classification by a group of 9 surgical pathologists, all in the day-to-day practice of pathology. Although many consensus diagnoses were made only after spirited discussion by the Group, the results suggested that general surgical pathologists can perform nearly as well as lymphoma experts. A comparison of the incidence of Hodgkin's disease and distribution of Rye subtypes in Western Australia with 4 other populations showed a similar overall incidence but appreciable variation in the relative frequency of the subtypes--mainly in the proportions of nodular sclerosing and mixed cellularity.

Trophoblastic pseudotumor of the uterus: case report and ultrastructure.

A trophoblastic pseudotumor occurring in a young woman 6 months after a normal pregnancy is reported. Ultrastructural investigation demonstrated a close structural relationship between the infiltrating cells and those of the trophoblastic components of the normal human placenta, especially those seen in the primary villi of the developing placenta.