Invasive secretory (juvenile) carcinoma arising in ectopic breast tissue of the axilla.

Mammary carcinoma arising in ectopic breast tissue is an uncommon occurrence. Most reported cases have involved ductal carcinoma, but other types, such as medullary, papillary, and lobular carcinomas, have been described. For pathologists, the diagnosis of mammary carcinoma arising in ectopic breast tissue can be difficult, especially in the axilla, where carcinoma of adnexal origin must be excluded. We describe a 46-year-old woman who developed invasive (juvenile) secretory carcinoma in ectopic right axillary breast tissue and micrometastatic carcinoma in an ipsilateral axillary lymph node. The carcinoma arose in a right axillary mass that had been present for 8 years, from which she had secreted fluid during prior breast-feeding. To our knowledge, this is the first report of secretory carcinoma arising in axillary breast tissue to be documented in the current literature.

Diffuse angiomatosis of the extremities presenting as a sarcoma.

Diffuse angiomatosis of the extremities is a rare condition characterized by extensive or multifocal benign mass-forming vascular lesions involving multiple tissue planes; histologically, adipose and fibrous tissue are admixed with vascular elements that vary from capillary proliferations to large vessels that are often structurally abnormal. Although diffuse angiomatosis most likely represents a hamartomatous form of arteriovenous malformation, it behaves clinically as a benign but slowly progressive and unresectable neoplasm. We describe a case of diffuse angiomatosis of the lower extremity that presented clinically as a soft-tissue sarcoma.

Dysplastic cardiac development presenting as cardiomyopathy.

Multiple manifestations of disordered or arrested cardiac muscle development are reported in a 14-year-old boy with clinical evidence of heart disease. These include persistent noncommunicating intramyocardial sinusoids, anomalous right ventricular muscle bands, muscular deficiency of ventricular septum, and papillary muscle underdevelopment. To our knowledge, this complex of findings has not been previously described.

Histiocytic appearance of metastatic lobular breast carcinoma.

Autopsy findings in a case of widely disseminated lobular breast carcinoma showed an unusual histiocytoid appearance in metastases to the uterus and parathyroid gland. This morphology for breast carcinoma has been previously reported in eyelid metastases. Recognition of this pattern in other metastatic sites has important diagnostic and therapeutic implications. Problems might have arisen if the polypoid uterine mass had been the presenting lesion during life. We also review the occurrence of metastatic breast carcinoma in the uterus and parathyroid gland.

Congenital posthemorrhagic hydrocephalus: report of a case.

A newborn infant with hydrocephalus was found to have residua of subependymal-intraventricular hemorrhage and associated obliterative arachnoiditis. This process is well known in the postnatal period but not as an in utero event. The present article documents antenatal intraventricular hemorrhage as a cause of hydrocephalus.

Regulation of cathepsin D metabolism in rabbit heart: evidence for a role for precursor processing in the control of enzyme activity.

Production of active lysosomal enzymes may involve limited proteolysis of inactive high molecular weight precursors. Precursor processing potentially regulates lysosomal enzyme activity. To test whether rabbit cardiac cathepsin D is first synthesized as a precursor and whether prolonged fasting (a condition affecting both cathepsin D and total cardiac protein turnover) influences precursor processing, rates of cathepsin D synthesis and processing were compared in left ventricular slices of control and 3-d-fasted rabbits incubated in vitro with [(35)S]methionine. (35)S-labeled cathepsin D was isolated by butanol-Triton X-100 extraction, immunoprecipitation, and dodecyl sulfate-polyacrylamide gel electrophoresis. Total cardiac protein synthesis was measured by tracer incorporation and normalized for differences in precursor pool size by direct measurement of [(35)S]aminoacyl-tRNA-specific radioactivity. Relative cathepsin D synthetic rates were obtained by comparing (35)S incorporation into cathepsin D with (35)S incorporation into all cardiac proteins. Enzyme processing was assessed in pulse-chase experiments and assayed by autoradiography. The results indicate that (a) rabbit cardiac cathepsin D is synthesized as a precursor (53,000 mol wt) that is processed to a 48,000-mol wt form, (b) rates of both cathepsin D and total cardiac protein synthesis are similar in control and fasted rabbits, suggesting that decreased enzyme degradation rather than increased synthesis is responsible for the elevated levels of cardiac cathepsin D in starvation, and (c) cathepsin D processing in hearts of fasted animals is incomplete, with accumulation of the precursor during pulse-chase experiments of 6 h duration. Based upon these results, a three-stage model for the regulation of cathepsin D activity in rabbit heart is proposed.

Rabbit cardiac immunoreactive cathepsin D content during starvation-induced atrophy.

To determine whether the increased activity of cathepsin D observed during starvation-induced cardiac atrophy results from activation of preexisting enzyme or synthesis of new enzyme, a solid phase double-antibody radioimmunoassay was developed for measurement of immunoreactive cathepsin D in extracts of rabbit myocardium. Cathepsin D activity was significantly increased in the hearts of animals starved for 3, 7, and 14 days (82.6 +/- 0.8, 87.2 +/- 3.8, and 95.3 +/- 3.5 U/g wet wt, respectively) compared to controls (65.5 +/- 1.4 U/g wet wt; P less than 0.001). Immunoreactive cathepsin D was increased to a greater extent (168 +/- 7, 179 +/- 16, 200 +/- 17, and 104 +/- 5 micrograms/g wet wt for 3-, 7-, and 14-day starvation and controls, respectively; P less than 0.001) than that expected on the basis of the observed increase in enzyme activity. Sephadex G100 gel filtration of cardiac lysosomal extracts from starved and control animals revealed no evidence of high or low molecular weight forms of cathepsin D. The results suggest the observed increase in cathepsin D activity during starvation-induced cardiac atrophy is accompanied by an increased synthesis and/or decreased degradation of cathepsin D protein, rather than activation of preexisting enzyme. The lower activity levels observed during starvation possibly result from alterations in the concentrations of endogenous inhibitors or activators of cathepsin D.