PubMed · 10469221
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M Sur, K Cooper. 1999. PNETs everywhere.. https://doi.org/10.1046/j.1365-2559.1999.0781a.x
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BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a hypercellular, storiform, CD34-positive low-grade sarcoma with honeycomb entrapment of fat, which typically involves the trunk and extremities. Nuchal-type fibroma (NTF ) is a paucicellular, CD34-positive fibrous tumor with fat entrapment, which may occur in both nuchal and extranuchal locations and in association with Gardner syndrome. METHODS: We report the association of DFSP with NTF in a 43-year-old male with no personal or family history of Gardner syndrome. RESULTS: The patient had a past history of a DFSP removed from his back, which recurred 2 years later and was re-excised. Additionally, the patient had a typical NTF, in the posterior neck, removed at the same time. Histopathologic examination of the recurrent back lesion demonstrated a composite lesion with typical appearances of DFSP, centrally, blending into an NTF-like appearance, peripherally. Both components expressed CD34 and CD99, and lacked elastin. A review of the microscopic slides of the patient's previously excised DFSP revealed an identical lesion with surrounding NTF-like areas. CONCLUSION: While an association between NTF and fibromatosis has recently been reported, this is to our knowledge the first report of an association between NTF and DFSP. The morphologic findings suggest that there may be a continuum between these two CD34-positive lesions that have a tendency to infiltrate adipose tissue and recur.
OBJECTIVE: To compare the clinical and morphological features of impalpable and palpable cryptorchid testes, as there is debate about how much effort is appropriate to bring an impalpable undescended testicle into the scrotum. PATIENTS AND METHODS: We reviewed retrospectively 189 cases of undescended testicles in 168 patients who were explored surgically by one surgeon between August 1997 and September 2000. Operative findings of palpability, testicular size and location were collected. The mean tubular diameter (MTD), tubular fertility index (TFI) and mean number of germ cells per tubule (MGCT) were calculated using immunohistochemistry for CD-99, a Sertoli-cell marker, to classify germ cells more accurately. RESULTS: Sixty-three testes (33%) were impalpable; the median age at the time of surgical exploration was 23 months for both groups. The mean (sd) testicular volume for the impalpable and palpable groups were 0.83 (0.38) and 1.22 (0.54) mL, respectively. Using fitted curves of size vs age, impalpable testes were smaller than palpable testes at all ages, with the difference nearly statistically significant (P < 0.06). The MTD, TFI and MGCT decreased with age in both groups, with no statistically significant differences between the groups. A sub-analysis of abdominal and extra-abdominal testes confirmed no significant differences. CONCLUSION: Impalpable testes are smaller at the time of exploration than palpable cryptorchid testes. However, histological factors predict that impalpable testes have a significant chance of future fertility and therefore orchidopexy is appropriate. CD-99 immunohistochemistry makes objective morphological information easier to obtain.
The CD99 antigen has been implicated in various cellular processes, including apoptosis in T cells. Previously, we reported two monoclonal antibodies that recognize different epitopes of the CD99 molecule, named DN16 and YG32. In this study, we investigated the role of each CD99 epitope in T cell apoptosis. Unlike the DN16 epitope, CD99 ligation via the YG32 epitope failed to induce T cell death. Surprisingly, however, the YG32 signal enhanced Fas-mediated apoptosis in Jurkat T cells. Augmentation of Fas-mediated apoptosis by YG32 ligation was inhibited by treatment with either of the caspase inhibitors z-VAD-fmk or z-IETD-fmk, and YG32 ligation appeared to induce Fas oligomerization. These results suggest that each CD99 epitope plays a distinct role in T cell biology, especially in T cell apoptosis.