C. Parsons

Radiation-induced brachial plexus injury: follow-up of two different fractionation schedules

All 449 breast cancer patients treated with post-operative radiotherapy to the breast and lymph nodes between 1982 and 1984 have been followed for 3-5.5 years. In this group two different fractionation schedules were used, one five times a fortnight and one daily, both over 6 weeks. The calculated dose to the brachial plexus was 45 Gy in 15 fractions or 54 Gy in 30 fractions. These schedules are equivalent doses using the standard NSD formula. The diagnosis of a brachial plexus injury was made clinically and computed tomography was used to distinguish radiation injury from recurrent disease. The actuarial incidence of a radiation-induced brachial plexus injury for the whole group was 4.9% at 5.5 years. No cases were seen in the first 10 months following radiotherapy. The incidence rises between 1 and 4 years and then starts to plateau. When the large fraction size group is compared with the small fraction size group the incidence at 5.5 years is 5.9% and 1.0%, respectively (p = 0.09). Two different treatment techniques were used in this group but were not found to contribute to the probability of developing a brachial plexus injury. It is suggested that radiation using large doses per fraction are less well tolerated by the brachial plexus than small doses per fraction; a commonly used fractionation schedule such as 45 Gy in 15 fractions may give unacceptably high brachial plexus morbidity; and the use of small doses per fraction or avoiding lymphatic irradiation is advocated.

Accuracy of CT in detecting squamous carcinoma metastases in cervical lymph nodes

The accuracy of computed tomography (CT) in the assessment of nodal metastases was correlated retrospectively with the pathological examination in 28 patients with known head and neck squamous cell carcinoma, who underwent neck dissections. Three patients had bilateral neck dissections resulting in a total of 31 dissections. CT scanning correctly staged 28 of 31 neck dissections providing an accuracy of 90%, a sensitivity of 87.5% and a specificity of 100% in the detection of nodal metastases. Of the 21 true positives, underestimation of the extent of nodal disease occurred in seven cases. Regarding extracapsular nodal spread, CT resulted in an accuracy of 62%, a sensitivity of 62.5% and a specificity of 60%. All three false negatives for nodal metastases occurred in metastatic spread to the submandibular nodes. The existing criteria for assessment of nodal metastases with CT are sensitive and specific, but in the assessment of extranodal spread CT may not detect 37.5% of cases.

Lymphography—current role in oncology

A review of the use of lymphography at this hospital, a major oncology centre, is presented. The advent of computed tomography has brought a dramatic reduction in the number of lymphograms currently performed for diseases such as lymphoma, testicular tumours and gynaecological malignancies. This study analyses the reasons for this decline, and concludes that valuable information can still be obtained from lymphography in certain selected groups of patients.

The accuracy of mammography alone and in combination with clinical examination and cytology in the detection of breast cancer

The accuracy of mammography alone and in combination with clinical examination and aspiration cytology was assessed in 402 patients who attended the Early Diagnostic Unit of the Royal Marsden Hospital, London. The sensitivities of mammography, clinical examination and cytology in identifying breast cancer were 76.9%, 81.7% and 63.5% respectively; the specificities of each test were 90.0%, 87.6% and 99.3%. The calculated sensitivity was increased to 96.2% if one positive test out of the three was regarded as an indication to undertake breast biopsy. If this approach was adopted the number of breast cancers missed would be two out of 104 and the yield of positive biopsies would be approximately one in four (27.6%). The implications of proceeding to breast biopsy on the basis of a single positive test are discussed.

Focal myositis, a benign inflammatory pseudotumour: CT appearances

Focal myositis is a rare benign pseudotumour of skeletal muscle, of unknown cause. Clinically it presents as an enlarging mass within muscle, usually of an extremity, and is often mistaken for a soft tissue neoplasm. The diagnosis is made by biopsy which reveals characteristic histological changes of inflammation, focal degeneration and regeneration, and some evidence of denervation. The CT findings include irregularity and enlargement of the muscles involved, with diffuse, poorly defined fatty infiltration of the muscle planes, but no evidence of an associated mass. We present two cases of focal myositis of the calf, both of which mimicked a soft tissue neoplasm, and in which CT was helpful in determining the nature and extent of the abnormality, for needle biopsy, and follow-up.

The anatomy and pathology of the brachial plexus as demonstrated by computed tomography

Computed tomography (CT) scanning can demonstrate a wide range of abnormalities affecting both the brachial plexus and the surrounding structures. Narrow section (4 mm) CT was used with bolus intravenous enhancement to examine the root of the neck and axilla in 62 patients with cancer, many of whom had symptoms of brachial plexus neuropathy. The normal anatomy of the plexus and its relations are described and illustrated. Examples of pathological changes caused by tumour and irradiation are also presented. The narrow scanning width (4 mm) is needed as the details sought are small and will be missed on thicker slice widths, particularly the changes of fibrosis in the upper axilla. Injection of intravenous contrast medium is essential for identifying the vascular structures which are used to locate the brachial plexus, especially when disease processes and post-irradiation fibrosis have destroyed the tissue planes.

The Diagnosis by Computed Tomography of Brachial Plexus Lesions Following Radiotherapy for Carcinoma of the Breast

The region of the brachial plexus in the root of neck and axilla was examined by computed tomography (CT) in 62 patients attending the Royal Marsden Hospital. Forty-two of these patients had been treated by surgery and subsequent radiotherapy for carcinoma of the breast. Computed tomography was able to identify varying grades of abnormality that were ascribed to radiation fibrosis. Twenty-eight patients had neurological symptoms affecting the arm or hand on the treated side and CT changes were seen in 96%. The grading and significance of these CT abnormalities is discussed. The patients had been treated by two different radiotherapy techniques (three-field and four-field) which utilised either a large or small treatment fraction. The higher grades of abnormality on CT were seen in 57% of those treated with the large fraction size and 27% of those treated with the small fraction size. However, the changes on CT did not relate to the different radiotherapy techniques.

Benign mimics of soft tissue sarcomas

We reviewed all new patients referred for treatment to the Sarcoma Unit at the Royal Marsden Hospital with a clinical diagnosis of soft tissue sarcoma (STS) during the course of 1 year (1989-1990). Of 118 patients, 65 (55.1%) had primary STS, 26 (22.0%) had recurrent STS, 19 (16.1%) had benign soft tissue tumours and eight (6.8%) had malignant tumours other than STS involving soft tissues and presenting clinically as soft tissue tumours. All patients underwent CT scanning which was used to assist diagnosis, assess operability or for radiotherapy planning. The CT findings of the benign lesions, all clinically suspicious of sarcoma, are discussed. The role of CT in the identification and management of these cases is emphasized.

Computed tomographic scanning in patients with carcinoma of the tongue.

Computed tomographic (CT) scanning is useful for staging patients with carcinoma of the tongue. In a study of 13 patients scanned prior to treatment, CT gave additional valuable information about the primary tumour in four patients. Computed tomography detetected non-palpable, abnormal cervical lymph nodes in three patients which directly affected the nature of the subsequent operation.

A quantitative analysis of the spatial relationships of grouped microcalcifications demonstrated on xeromammography in benign and malignant breast disease

The mammograms of 444 patients who had a breast biopsy leading to a definitive histological diagnosis were reviewed. In 21 cases (4.7%) grouped microcalcifications were identified as the only mammographic abnormality. These groups of microcalcifications were analysed to determine whether there was any quantitative difference between benign and malignant lesions with respect to a shape parameter of the group, the spatial frequency of the particles and neighbour-to-neighbour relationships of the particles. This analysis did not reveal any significant difference between the spatial relationships of the grouped microcalcifications found in benign and malignant breast disease.