Desmoplastic small round cell tumors of the abdomen.

BACKGROUND: Desmoplastic small round cell tumors (DSRCT) have been only recently identified. METHODS: The authors report DSRCT in two pediatric patients (an 8-year-old boy and 12-year-old boy). In both patients, the initial diagnosis was rhabdomyosarcoma. The resistance to standard chemotherapy and radiation therapy prompted the authors to review the initial biopsy specimens and perform complementary immunophenotypic characterization. RESULTS: These analyses revealed that the tumor cells were strongly positive for keratin epithelial marker antigen, desmin, vimentin, neurospecific enolase, and S100 protein, corresponding to pleomorphic differentiation, characteristic of DSRCT: CONCLUSIONS: The authors suggest that extensive immunohistologic characterization be performed in all cases of small round cell tumors of the abdomen so that the diagnosis of DSRCT is not overlooked. These rare tumors are refractory to chemotherapy, and initial aggressive surgery is warranted.

Studies of monoclonal antibody BL2-10D1 as a marker for the detection of the urothelial origin of tumors.

BACKGROUND: In previous studies, the authors demonstrated the value of the monoclonal antibody (MoAb) BL2-10D1 in identifying malignant transitional cells. In this study, the authors evaluate the possible diagnostic value of a murine MoAb, BL2-10D1, raised against human bladder cancer in the determination of the urothelial origin of metastases in a series of 29 patients with metastatic bladder or prostatic carcinoma. METHODS: Using an immunoperoxidase method, BL2-10D1 and anti-prostate-specific antigen (anti-PSA) reactivity were studied, using histologic sections from 18 pelvic lymph nodes and 4 other anatomic sites invaded by transitional cell cancer, and from 7 pelvic lymph nodes containing prostatic cancer. RESULTS: All lymph nodes containing metastases of transitional cell carcinoma were positive with BL2-10D1, whereas all metastases of prostatic cancer were negative; the four instances of distant urothelial metastases were positive with BL2-10D1 MoAb. Conversely, anti-PSA reacted only with prostatic metastases. CONCLUSION: Thus, MoAb BL2-10D1 and anti-PSA complement each other in the separation of cancers of prostatic and urothelial origin, and the BL2-10D1 MoAb has potential usefulness in differentiating between urothelial carcinoma and prostate adenocarcinoma. In patients with bladder tumors of uncertain origin, BL2-10D1 may be helpful in confirming that a tumor is a transitional cell carcinoma.

Successful treatment for a metastatic supratentorial malignant rhabdoid tumor.

The case of a boy with a familial history of Rendu-Osler disease, who successively developed a cerebellar pilocytic astrocytoma (at 3 years of age) and a metastatic supratentorial malignant rhabdoid tumor (at the age of 12 years) is reported. After a complete surgical removal, the CSF was cleared by 4 courses of chemotherapy, and the child received a craniospinal irradiation. He is currently alive and well 19 months after completion of the treatment. The authors discuss the ethiopathogeny of such intracranial tumors and argue for aggressive treatment.

Nevi, other than dysplastic and Spitz nevi.

Cutaneous nevi are common lesions that develop by proliferation of melanocyte-derived cells. The majority develop as junction nevi from melanocytes at the epidermo-dermal junction. Cells from this proliferation pass into the underlying dermis forming compound nevi. Later junctional melanocytic activity ceases, leaving an intradermal nevus. A minority of nevi, mainly blue nevi, arise from intradermal melanocytes. Histological variants of melanocytic nevi exist and can be the source of difficult diagnostic problems. Nevi are important as clinical and histological simulators of cutaneous melanoma, as precursor lesions for melanoma (although the actual chance of malignant transformation of an individual nevus is low) and as cosmetic problems (mainly large congenital nevi). Cutaneous nevi are to be separated clinically and histologically from melanomas that are comprised of nevocyte-like cells (minimal deviation melanoma).

[Giant cell fibroblastoma. Apropos of 2 cases]. / Le fibroblastome à cellules gèantes. A propos de deux observations.

Two cases of giant cell fibroblastoma (GCF) are reported. One presented as cervical tumor in a 11 year old child and the second localized in axillar region of 14 year old boy. Histologically both showed a typical distinctive appearance of this entity when focal fusocellular cells arranged in a storiform pattern was also constated in one. The immunohistochemical and ultrastructural study ruled out a vascular origin. The clinical and pathological findings suggest that CGF represent a juvenile form of dermatofibrosarcoma protuberans.

[Adenosarcoma of the uterus. Review of the literature. A case report]. / L'adénosarcome utérin. Revue de la littérature. A propos d'un cas.

Adenosarcoma is a rare tumour of the uterus which contains normal benign epithelial cells together with sarcomatous over-growth of the stroma. The tumour is an intracavitary one which gives rise to bleeding but has a relatively favourable prognosis because it has a low degree of malignancy.

Visualization and rapid quantification of autoradiographic labeling in scanning electron microscopy applied to localization of receptor sites on the surface of whole cells.

The use of backscattered electron imaging (BEI) as a routine procedure for examining autoradiographic reactions in scanning electron microscopy (SEM) is described. This technique allows the determination of the number of receptor sites occupied by 125I-epidermal growth factor (EGF) on whole cells. The effect of 1.25 dihydroxyvitamin D3 (1,25 (OH)2D3) on the number of epidermal growth factor receptors (EGF-R) in the BT 20 human mammary carcinoma cell line (which is known to possess a very high number of EGF-R) has been evaluated with this method. To compare the silver grain density over the cells (controls and 1,25 (OH)2D3-treated cells) we used an image analysis system Quantimet 900. The results were compared with those of a previous study using transmission electron microscopy (TEM). This study confirmed the results obtained with TEM and showed the even distribution of receptors sites on a single cell and a large difference in the number of receptor sites from one cell to another. The use of BEI to visualize the autoradiographic reaction in SEM allowed the examination of a large surface with good contrast and resolution and eliminated artefacts not corresponding to the silver grains. It gave new information not delivered by quantitative TEM autoradiography and was easier and faster to use. The efficient use of SEM autoradiography combined with BEI could facilitate whole area distribution mapping of radioactive labeling.

[Angiosarcoma of the breast. Apropos of 4 cases with a review of the literature]. / L'angiosarcome du sein. A propos de quatre cas avec revue de la littérature.

Four cases of angiosarcoma of the breast were treated at Centre Léon-Bérard in Lyon. It is a rare malignant vascular tumor, constituting < 1% of all primary breast lesions. Radical local surgery is the treatment of choice; however, local recurrences and metastases are frequently observed. The 3-year disease-free survival rate is < 15%. The role of irradiation and adjuvant chemotherapy remains to be evaluated. Doxorubicin-ifosfamide-GM CSD gave a positive response in one case with metastases.

Expression of integrin receptors on 45 clinical neuroblastoma specimens.

Immunohistological expression of integrins has been analyzed on 45 neuroblastoma specimens representative of the different clinical and histological forms of the tumor. None of the specimens expressed the alpha 5 chain of the integrins. The beta 1 chain was expressed on all specimens, the alpha 1 chain on 44 specimens and the alpha 3 chain on 42; the 4 specimens which lacked alpha 1 or alpha 3 were stage-4 neuroblastomas. The alpha 2 chain was expressed on 18 specimens, and the alpha 6 chain on 17; 15 reacted with both. Their reactivity was related to the maturation of the tumor rather than the stage of the disease: they were expressed on low-grade, well-differentiated specimens; stage 3-4 neuroblastoma specimens analyzed at diagnosis were negative, but usually expressed both chains when analyzed after in vivo differentiation by chemotherapy. alpha v reacted with 18 specimens and beta 3 with 12, without strict relation with the stage of the disease and/or its degree of differentiation; 9 well-differentiated specimens expressed the beta 4 chain; only 4 well-differentiated specimens expressed the alpha 4 chain. The 4 specimens which lacked alpha 1-beta 1 or alpha 3-beta 1 expression had n-myc amplification, whereas those which expressed either alpha 4, beta 4, beta 3 or alpha v had no amplification. Furthermore, the expression of the 3 heterodimers alpha 4-beta 1, alpha v-beta 3 and alpha 6-beta 4 was essentially observed on primary tumors which developed in the mediastinum. The expression of alpha 2-beta 1 and alpha 6-beta 1 was observed on both n-myc-positive and -negative specimens. beta 1 and alpha 3 were diffusely expressed on all counterparts of these tumors, from undifferentiated neuroblasts to ganglion and Schwann cells. The alpha 1 chain reacted with undifferentiated and intermediate neuroblasts as well as with Schwann cells, but ganglion cells were negative. alpha 2 and alpha 6 chains were negative on undifferentiated neuroblasts, variably expressed on intermediate neuroblasts, and restricted to Schwann cells in ganglioneuroma. The expression of alpha 4 and beta 4 was restricted to Schwann cells. alpha v and beta 3 occasionally reacted with undifferentiated and intermediate neuroblasts; alpha v was strongly positive on Schwann cells but negative on ganglion cells, whereas beta 3 was positive on both neuronal and non-neuronal populations.

Expression of leucocyte adhesion molecules on 66 clinical neuroblastoma specimens.

LFA-3, ICAM-1, HLA.ABC and HLA.DR expression was analyzed on 66 neuroblastoma specimens. HLA.ABC was expressed on 26 specimens, HLA.DR on 2, LFA-3 on 20 and ICAM-1 on 10. HLA.ABC and LFA-3 were positive on ganglioneuroblastoma or ganglioneuroma, but they were negative on neuroblastoma, independently of the clinical staging; HLA.ABC and LFA-3 were induced in vivo by chemotherapy in parallel with tumoral cell differentiation, in both the primary and the metastases. The expression of ICAM-1 was restricted to 5 of the 10 low-grade stage-1 or stage-2 specimens, 1 stage-3 specimen, and the primary tumors of 2 patients with stage-4 disease, analyzed hence at diagnosis and after chemotherapy (4 specimens); metastatic cells obtained in 1 of these patients were negative. HLA.ABC and LFA-3 expressed on both mycN-negative and -positive specimens, whereas ICAM-1 was restricted to MYCN-negative specimens. LFA-3 diffusely stained partially differentiated neuroblasts, Schwann cells and ganglion cells. The expression of HLA.ABC on differentiated neuroblasts varied from one sample to another and within the same tumor; Schwann cells were strongly positive, but ganglion cells were negative. In positive samples, ICAM-1 was expressed on differentiated neuroblasts and Schwann cells, but negative on ganglion cells; however, most of the differentiated tumors were ICAM-1-negative, suggesting ICAM-1 induction by unknown local signal. The 4 markers were negative on undifferentiated neuroblasts. The distribution of these 4 markers on clinical specimens was in agreement with their reactivity on fetal tissues, as well as with results obtained on neuroblastoma cell lines before and after in vitro treatment with IFN-gamma.