1/8. Complete spontaneous regression of Merkel cell carcinoma: a review of the 10 reported cases.BACKGROUND: Merkel cell (neuroendocrine) carcinoma (MCC) is a very aggressive primary cutaneous neoplasm occurring most often on the head and neck of the elderly. Complete spontaneous regression (CSR) of MCC was first described in 1986. Since then other cases have been reported bringing the total to 10. OBJECTIVE: To review these 10 cases and obtain long-term follow-up data, to compare them for similarities and differences. METHOD: Each original case report was extensively reviewed and authors contacted in most cases for confirmation and updated information. RESULTS: In no case did MCC recur after CSR was noted, although follow-up information in some cases was short. When CSR occurred, it was swift and dramatic with complete regression of skin and lymph node metastasis in 1-3 months. CONCLUSION: While only 10 cases of CSR is a small number, MCC is itself a rare malignancy with just over 600 reported cases. Today most cases of MCC receive aggressive combined therapy effectively precluding diagnosis of CSR. The nature of regression in these 10 cases may point toward future immunologic therapy just as similar cases of CRS in patients with melanoma have led to advances in the immunologic treatment for that malignancy.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/8. Regressing atypical histiocytosis, a regressing cutaneous phase of Ki-1-positive anaplastic large cell lymphoma. Immunocytochemical, nucleic acid, and cytogenetic studies of a new case in view of current opinion.BACKGROUND. Regressing atypical histiocytosis is a rare multifocal cutaneous tumor characterized by large, spontaneously regressing, ulcerating skin nodules. Although initially self-remitting, the condition may progress to systemic lymphoma. methods. Using material from one patient, an attempt was made to clarify the nature of this condition with immunophenotyping, genotyping, and chromosome studies. RESULTS. immunophenotyping studies indicated the condition was of T-cell lineage, although T-cell receptor gene studies showed polyclonal rearrangement. This case progressed to systemic lymphoma. CONCLUSIONS. The authors believe regressing atypical histiocytosis is a regressing phase of Ki-1-positive anaplastic large cell lymphoma of the skin.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/8. Spontaneous regression of subcutaneous metastasis of cutaneous melanoma.A case is presented of a 44-year-old Caucasian man who was operated on in October of 1988 for a cutaneous melanoma in his trunk and who in the space of 1 year manifested a single subcutaneous nodule compatible with a metastasis of melanoma by fine-needle aspiration biopsy. No other abnormal findings were revealed by physical and instrumental examinations. During the subsequent hospitalization, we witnessed (in conjunction with the occurrence of painful symptoms in the hands of an inflammatory nature) the total, progressive, spontaneous regression of the metastasis, which was confirmed by the clinic and the tests. After 15 months of follow-up, the patient has not shown any further signs of illness.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
4/8. Transient spontaneous regression of mass effect with glioma.A spontaneous regression of the lesion seen in sequential computertomographic scans does not necessarily indicate a non-neoplastic nature of the pathological process. Two patients with pathologically verified glioma of the brain which showed a temporary regression of the mass effect are reported, and the mechanism of the regression of computertomographic mass signs is discussed.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
5/8. lymphomatoid papulosis in an 11-month-old infant.lymphomatoid papulosis was seen in an 11-month-old child. The condition resolved spontaneously after a course of only 8 weeks and the patient has now been disease free for 9 months. Electron microscopy showed infiltrating lymphocytes with cleaved nuclei suggestive of T cells. Monoclonal antibody studies confirmed the T cell nature of the infiltrate. In this case, suppressor (OKT8) T cells were more prominent than helper (OKT4) T cells, in contrast to previous reports.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
6/8. Spontaneous regression of malignant melanoma: a review of the literature on incidence, clinical features, and possible mechanisms.A review of the clinical features of spontaneous regression of malignant melanoma was undertaken. Thirty-three patients with total regression of primary melanoma ("primary regressors") and 40 (13 of whom were somewhat doubtful) with regression of metastatic disease were reviewed in detail. These patients appeared to represent a typical age incidence of melanoma but the primary regressors showed an unexpected predominance of male over female patients. A variety of unique clinical features of the histories of the patients were noted, but none appeared to explain the regression with any degree of predictability. Cutaneous metastases constituted the most common site of regression, followed, in order, by lymphatic, pulmonary, and hepatic metastases. About 40% of patients with spontaneous regressions appeared to have "spontaneous cure," which implies that the disease had not relapsed either during a long period of follow-up or until death from some other cause. Mechanisms that possibly relate to spontaneous regression of melanoma fall into the following general categories: immunologic, endocrine, pigment metabolic, intracellular, nutritional, and carcinogenic. Further quantitative studies of patients acutally undergoing spontaneous regression or the development of a model of spontaneous regression may be a key to our understanding of this interesting "experiment of nature."- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
7/8. Infantile myofibromatosis: report of two cases.Two cases of solitary type infantile myofibromatosis (IM) were presented. Case 1 was a 6-month-old male infant with a firm, dark red, fixed tumor on his right knee. A computerized tomographic scan revealed that the tumor was attached to the underlying muscle. Case 2 was a 1-month-old male infant with a tumor on his right knee, similar to that in case 1. In neither case was there any clinical evidence of visceral involvement. Histological and immunohistochemical findings were similar. The lesions appeared histologically as non-encapsulated nodules composed of whorled fascicles of spindle-shaped cells and a vascular element with a hemangiopericytoma-like appearance. The tumor cells were positively stained with PTAH. They were positive for alpha-smooth muscle actin and vimentin, but negative for desmin. These findings support the myofibroblastic nature of IM. In case 2, the tumor regressed spontaneously at the age of 12 months. Unlike the multicentric form, spontaneous regression of the solitary form of IM has not previously been reported.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
8/8. Pulmonary metastasis of benign giant cell tumor of bone. Six histologically confirmed cases, including one of spontaneous regression.Benign giant cell tumor of bone, despite being classified as benign, has the unusual ability to metastasize. Metastasis of such a tumor has been thought to be rare, with only approximately 50 such cases having been reported. However, as awareness of the metastatic potential of these tumors has increased, and methods of detection have improved, metastasis of benign giant cell tumor has been increasingly recognized. Six patients with pulmonary metastasis of giant cell tumor have been treated at a los angeles hospital since 1980. This represents 9.1% of all patients treated for benign giant cell tumor of bone over the same period at this institution, a higher rate than that encountered in previously published series. The early detection and treatment of this tumor is important, because those with complete resection of tumor have the best prognosis. The nature of these pulmonary metastases remains unpredictable, however, as evidenced by two of the cases in this series: one of spontaneous regression, and another of death caused by pulmonary failure.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |