Primary cutaneous nevoid melanoma with Homer-wright rosettes: a hitherto unrecognized variant with immunohistochemical and ultrastructural study.

We report a case of cutaneous nevoid melanoma manifesting as a growing and pruritic pigmented lesion of the back in a 43-year-old woman. The lesion measured 1.2 cm in its largest dimension. The salient microscopic features were discrete dermal nests of palisading tumor cells and a central fibrillary tangled core. Other features were microscopically consistent with melanoma: irregular tumor cell nesting associated with upward migration of melanocytes and consumption of the epidermal component, lack of maturation, expansile growth pattern, and a tendency to confluence of the dermal nests. No prominent mitotic activity was recognized. Breslow thickness was 1.3 mm. Tumor cells were positive for HMB45, Melan A, tyrosinase, and S100 protein. The MIB-1/ki-67 proliferative index was 2%. Histologic examination of a biopsy sample from the axillary sentinel lymph node was positive for small foci of melanocytic cells measuring 0.04 mm in their largest dimension.

Plasma cell myeloma presenting with diffuse pleural involvement: a hitherto unreported pattern of a new mesothelioma mimicker.

We described 2 cases of plasmacytoma presenting with a preponderant involvement of the pleural membranes simulating clinically, radiologically, and on gross pathologic inspection a primary mesothelioma. The patients were an 80-year-old man and a 45-year-old woman. In both cases, the clinical presentation was that of a serosal tumor, including effusions and pleural thickening. In the former, the serosal infiltration raised the suspicion of mesothelioma reinforced by history of occupational exposure to asbestos. Patient general condition deteriorated rapidly. Postmortem examination revealed unilateral encasing of the lung within a thick, irregular neoplastic rind. In addition, tumoral involvement was seen in the homolateral third rib and the clavicle. Histologic examination of pleural masses demonstrated diffuse infiltration by highly atypical, pleomorphic plasma cells with kappa chain restriction. In the second case, clinical presentation was also suspicious of mesothelioma. Nonetheless, a pleural biopsy specimen showed irregular sheets of plasma cells showing kappa light chain restriction. A bone marrow aspirate was also positive for abnormal plasma cell infiltrates. Despite chemotherapy, the patient died 4 months after presentation. Although rarely, it seems that plasmacytoma may present with an exclusive or preponderant pleural involvement; and it may therefore be added to the list of pseudomesotheliomatous tumors.

Effects of Delayed Hypothermic Machine Perfusion on Kidney Grafts with a Preliminary Period of Static Cold Storage and a Total Cold Ischemia Time of Over 24 Hours.

BACKGROUND Hypothermic machine perfusion (HMP) appears to exert a reconditioning effect on the ischemic damage of kidney grafts. However, some concerns still remain about its real effectiveness when it is delayed after a preliminary period of static cold storage (SCS) or with prolonged overall cold ischemia time (CIT). MATERIAL AND METHODS The effect of HMP on hemodynamic, metabolic, histological and ultrastructural features of grafts was investigated in 21 single-kidney grafts treated with a delayed HMP after SCS and with a total CIT of over 24 h. RESULTS The mean CIT, SCS, and HMP times were 29 h, 12 h, and 18 h, respectively. Longer SCS was associated with higher vascular resistance and lower arterial flow. In the pre- vs. post-HMP comparison, a significant decrease in arterial resistances and increase of flow were recorded. The hemodynamic improvement was independent of HMP duration. The perfused grafts retained some metabolic activity, with a statistically significant decrease of pH, pO2, and glucose levels, and increase of lactates in the perfusion liquid, by the end of HMP. Longer SCS was associated with higher pH and greater pO2 decrease during HMP. Light microscopy and transmission electronic microscopy revealed no significant variations in nuclear, cytoplasmic, or ultrastructural damage. SCS, HMP, and CIT were not identified as risk factor for delayed graft function or rejection. CONCLUSIONS A delayed and extended HMP can recover the graft hemodynamic function, maintain some metabolic activity, and stabilize the accumulated ischemic damage due to a preliminary SCS.

Eosinophil-rich squamous carcinoma of the oral cavity: a study of 13 cases and delineation of a possible new microscopic entity.

We report 13 cases of squamous cell carcinoma (SCC) of the oral cavity characterized by a prominent eosinophilic infiltration of the stroma. All patients were adults, 10 men and 3 women (aged 54 to 92 years; median, 71 years). They presented with tumors of the gingiva (5 cases), tongue (3 cases), palatine tonsil (2 cases), palate (2 cases), and mucosal aspect of lip (1 case). Metastatic involvement of regional lymph nodes was seen in 5 cases. The metastatic foci were associated with heavy eosinophilia as well. No patient had an abnormal eosinophil count in blood. Microscopically, the clusters of eosinophils were characteristically noticed in intimate admixture with the advancing edge of squamous carcinoma, either as nests or small tumor cords. The pattern of eosinophilic infiltration was comparable, regardless of tumor site or grade. Data from our series indicate that SCC with a reactive inflammatory infiltrate rich in eosinophils is consistently associated with stromal invasion. This observation may be useful in dealing with small tissue fragments where subepithelial stromal invasion cannot be easily assessed by conventional criteria. In addition, our data seem to confirm that eosinophil-rich SCC, although associated with metastatic involvement of cervical lymph node, seems to pursue a less aggressive course if compared with ordinary SCC.

Russell body gastritis: expanding the spectrum of Helicobacter pylori - related diseases?

We report a new case of Helicobacter pylori gastritis showing plasma cell infiltrates with extensive formation of Russell bodies (Mott cells) within the lamina propria of the antral mucosa. The patient was a 60-year-old woman with a history of epigastric pain. Endoscopy revealed non-specific congestion of the mucosa. Microscopically, the intracytoplasmic inclusions were homogeneous, mainly round to oval, and pushed the nucleus toward the periphery. They were intensely PAS-positive and reacted to antibodies against polytypic light chains, CD79a, and anti-plasma cell antibody. Because of the accumulation of intracytoplasmic inclusions, Russell body gastritis is a potential source of diagnostic difficulties in endoscopic biopsy specimens that can be confused with immunocytic neoplasms, such as lymphoplasmacytic lymphoma or plasmocytoma, or signet-ring cell carcinoma. In the light of similar cases published previously, it seems as if the association between Russell body gastritis and Helicobacter pylori infection is not merely coincidental.

Second Surgery in Insular Low-Grade Gliomas.

BACKGROUND: Given the technical difficulties, a limited number of works have been published on insular gliomas surgery and risk factors for tumor recurrence (TR) are poorly documented. OBJECTIVE: The aim of the study was to determine TR in adult patients with initial diagnosis of insular Low-Grade Gliomas (LGGs) that subsequently underwent second surgery. METHODS: A consecutive series of 53 patients with insular LGGs was retrospectively reviewed; 23 patients had two operations for TR. RESULTS: At the time of second surgery, almost half of the patients had experienced progression into high-grade gliomas (HGGs). Univariate analysis showed that TR is influenced by the following: extent of resection (EOR) (P < 0.002), ΔVT2T1 value (P < 0.001), histological diagnosis of oligodendroglioma (P = 0.017), and mutation of IDH1 (P = 0.022). The multivariate analysis showed that EOR at first surgery was the independent predictor for TR (P < 0.001). CONCLUSIONS: In patients with insular LGG the EOR at first surgery represents the major predictive factor for TR. At time of TR, more than 50% of cases had progressed in HGG, raising the question of the oncological management after the first surgery.

Intravesical botryoid adenocarcinoma of the prostate: report of an unusual growth pattern of prostatic carcinoma simulating a urinary bladder tumor.

We report on 3 cases of prostatic carcinoma presenting with a predominant intravesical mass as to simulate clinically and macroscopically a primary tumor of the urinary bladder. The patients were 65, 66, and 68 years old and presented with dysuria and micturition. All patients had a medical history of a prostatic adenocarcinoma diagnosed between 5 and 7 years earlier and treated conservatively. Because of instrumental evidence of a large urinary bladder mass, 2 patients underwent radical cystoprostatectomy based on suspicions for a primary urothelial tumor. Either cystoscopic or direct specimen inspection revealed a lobulated, yellow-tan, and polypoid lesion with a broad implant in the trigonal bladder area in 1 case and a mixed, polypoid, and diffuse linitis plastica-like infiltration of the bladder wall in the other 2 cases. Microscopically, sections of tumor mass as well as from the prostate featured a poorly differentiated adenocarcinoma compatible with the prostatic origin. Tumor cells were positive for prostate-specific antigen and prostatic acid phosphatase. Our cases suggest that an extensive polypoid growth pattern may be added to those patterns customarily observed in presenting prostatic carcinomas, raising treatment and diagnostic challenges.

Solitary fibrous tumor of the spinal cord: a clinicopathologic study of two cases.

Two cases of solitary fibrous tumor of the spinal cord are described. The patients were two men, 36 and 47 years old. Clinically, they sought medical care because of progressive paresthesias or urinary incontinence caused by a nodular, fairly circumscribed intraspinal tumor of the cervical and thoracic spinal cord, respectively. Preoperative magnetic resonance images suggested meningioma. In both cases, laminectomy with tumor resection was carried out. Microscopically, the tumors featured short spindle cells haphazardly enmeshed in a collagenized ground substance. No atypia, necrosis, or significant mitotic activity was recognized. Tumor cells were positive for CD34, bcl2, vimentin, and, in one case, CD99. Both patients recovered from symptoms and are alive and well 12 and 18 months, respectively, after surgical resection. The differential diagnosis includes meningioma, schwannoma, and hemangiopericytoma, all of which may occur in the spinal canal. A careful morphologic approach and the judicious use of immunohistochemistry may assist in distinguishing among these conditions, although some irreducible difficulties may be posed by hemangiopericytoma. Although solitary fibrous tumor of the spinal cord presents with fairly comparable clinical, instrumental, and pathologic patterns, we believe that compilation of more cases is needed to segregate it as a distinct clinicopathologic entity.