A total of 7251 histologically confirmed new cases of cancer (4117 males and 3134 females) were seen in the 6-year period 1979 to 1984 at the King Faisal Specialist Hospital and Research Centre in Riyadh, Saudi Arabia. The crude relative frequencies of cancer at various primary sites have been determined with reference to sex, age, geographic origin, and year of diagnosis. The most common cancer sites among males were non-Hodgkin's lymphomas, esophagus, lung, liver, stomach, and nasopharynx. Breast cancer was the most common tumor among the females, followed by non-Hodgkin's lymphomas and cancers of the thyroid, esophagus, cervix, and ovary. The most marked deviations were found in the Southern Region for cancers of the oral cavity (2.4 times higher), bladder (1.8 times higher), and lung (4.3 times lower). Known etiologic factors, such as local chewing, smoking habits, and schistosomiasis are likely to be responsible for these differences. Upward trends in cancers of lung, breast, colon and rectum, and the downward trend in esophageal cancer may reflect the rapid pace of modernization.

A series of fine‐needle aspiration biopsies (FNAB) from 76 children with round cell malignant tumors was studied by both light and electron microscopy. In 14 cases the material submitted for electron microscopy was inadequate, whereas in the remaining 62 biopsies a definitive diagnosis could be made. These included 29 malignant lymphomas, 8 neuroblastomas, 12 Ewing's sarcomas, 3 metastatic retinoblastomas, 3 Wilms' tumors, 3 rhabdomyosarcomas, and 4 unclassified tumors. The results from this study indicate that FNAB studied by light and electron microscopy can be effective in diagnosing small cell tumors in children.

A case study of desmoplastic small round cell tumor with divergent differentiation in a 13-yr-old boy is presented. Clinical, cytologic, histologic, immunohistochemical, and ultrastructural findings are reported. There was a close correlation between the various histologic and cytologic patterns. Immunohistochemical studies revealed strong positivity of many of the tumor cells for cytokeratin, vimentin, and desmin. Ultrastructurally, some of the tumor cells contained aggregates of cytoplasmic intermediate filaments. Fine-needle aspiration biopsy may suggest the diagnosis of desmoplastic small round cell tumor. Confirmation of the diagnosis may be provided by immunohistochemistry and electromicroscopy.

A series of 14 fine-needle aspiration biopsies (FNAB) from histologically proven cases of histiocytosis-x (Hx) were reviewed. The smears revealed a variable mixture of Langerhans cells, eosinophils, macrophages, polymorphonuclear cells, and giant cells. Based on the predominant cells present, the cases were further categorized as Langerhans cell predominant (nine cases), eosinophil predominant (two cases), and macrophage predominant (three cases). Langerhans cells were usually polygonal without significant evidence of phagocytosis and frequently contained indented nuclei. In three cases, several Langerhans cells showed prominent dendritic processes. Electron microscopy in 10 cases revealed Langerhans cells with varying degrees of morphologic differentiation. All cases studied revealed Birbeck granules. These findings indicate that FNAB may be an effective technique for diagnosing Hx.

We studied 12 children who presented with a recently recognized syndrome. The salient features of this new syndrome were recurrent fever; hepatosplenomegaly; pancytopenia: blond, golden to silvery gray hair; hypopigmented skin, progressive white maller demyelination; and early death. Seven patients died, four with severe central nervous system (CNS) involvement, and three with bone marrow failure and sepsis. Cutaneous anergy to recall antigens was present in all patients. Other immunological abnormalities were poor antibody Allergy Proc. istic distribution of melanin with melanocytes present in normal numbers but with fewer short dendritic processes. Langerhans' cells were present in normal numbers in some patients and sparse in others. This syndrome seems to cluster into two tribes from two d(fferent geographical areas in the ArabianPeninsula. In the eight families studied, 12 other siblings and close relatives were found to be affected. The mode of inheritance in this syndrome is that of an autosomal recessive pattern. We propose the term "PAID syndrome" to identify patients with the above features. (Allergy Proc 13, 6: 321-328, 1992)

Fine-needle aspiration biopsy specimens from 15 histologically proven cases of Ewing's sarcoma of the bone were studied by both light and electron microscopy. Large glycogen deposits in the Ewing's sarcoma cells could be easily recognized in smears stained routinely with Diff-Quik (American Scientific Product, McGraw Park, IL). These deposits appeared as punched-out clear spaces in the cytoplasm. Ultrastructurally the tumor cells could be divided into chief cells and dark cells. The chief cells were further categorized based on their nuclear morphologic features into cleaved, noncleaved, and intermediate cells. The dominant cell was noncleaved in eight, cleaved in three, and intermediate in four cases. All five tumors with abundant glycogen were composed predominantly of noncleaved cells. The tumor cells in aspiration material appeared to be irregular in shape, and some had cytoplasmic processes. In one tumor these processes were quite prominent; this caused some difficulty in differentiation from neuroblastoma.

In developed nations, Hodgkin lymphoma (HL) is rare in <5-year olds and represent a minority in developing countries. Little is reported about the biology and behavior of these very young patients compared with older children. 18.75% of our pediatric HL patients (0 - 14 years) were <5 years at diagnosis. This group had more boys, similar incidence of B-symptoms and stage distribution, less mediastinal involvement and bulky disease, and more mixed cellularity subtype than older children. Treatment included chemotherapy (CT; n = 55), combined modality therapy (CMT; n = 12) and XRT only (n = 2). Ten-year EFS and OS was 81.5% and 90.4%, respectively, versus 75.5% and 90.5% for older children (p > 0.5). A trend toward better survival was seen with CMT, using very LD-XRT, than with CT (OS 100% vs. 86.4%[p = 0.3]; EFS 90.9% vs. 81.0%[p = 0.4]). Although CT could be effective in a subset of LR patients, LD-XRT may be needed to effectively treat most of these patients. This dose reduction may reduce XRT-related toxicity, which can be significant in very young children.

Fine-needle aspiration biopsy (FNAB) smears from 16 cases of neuroblastoma are reviewed, and various cytomorphologic features helpful in diagnosing this tumor are described. Cytoplasmic processes were present in ten cases, and pseudorosettes in three cases. Electron microscopic study of FNAB samples revealed that all diagnostically important features, such as cell processes, neurosecretory granules, and synaptic cell junctions, could be recognized. These findings indicate that FNAB studied by light and electron microscopy is an effective method for diagnosing neuroblastoma.