Histologic Predictors of Recurrence in Mucinous Appendiceal Tumors with Peritoneal Dissemination after HIPEC

Background

Mucinous appendiceal tumors (MAT) are rare neoplasms that can metastasize to the peritoneum and often are treated with cytoreductive surgery (CRS) and HIPEC. Pathologic classification and outcomes vary, but standardized histologic definitions are emerging. We sought to evaluate outcomes in this disease after CRS/HIPEC using standardized pathologic criteria.

Method

Outcomes of MAT with peritoneal metastases (PM) after CRS/HIPEC from 2007 to 2015 were reviewed at our institution. Standardized histologic categories per WHO and consensus definitions were used: low-grade appendiceal mucinous neoplasm (LAMN), low-grade adenocarcinoma (LGAC), or high-grade adenocarcinoma (HGAC) primary tumors; and acellular mucin (AM), low-grade mucinous carcinoma peritonei (LGMCP), or high-grade mucinous carcinoma peritonei (HGMCP) peritoneal metastases. Cox proportional hazards model was used identify predictors of progression-free survival (PFS) by univariate and multivariate analyses.

Results

A total of 183 patients undergoing 197 CRS/HIPECs were included. Among 75 patients with primary histology review, there were 33 (44.0%) LAMNs, 28 (37.3%) LGACs, and 14 (18.7%) HGACs. Peritoneal histology was benign in 6 (3.0%), AM in 33 (16.8%), LGMCP in 114 (57.9%), and HGMCP in 44 (22.3%). PFS was not reached for AM, 34.3 months for LGMCP, and 16.8 months for HGMCP (p < 0.001). Peritoneal histology predicted PFS on multivariate analysis (hazard ratio 9.82 and 24.60 for LGMCP and HGMCP, respectively, vs. AM, p < 0.001). Among the LGMCP group, CEA and completeness of cytoreduction (CC score) predicted PFS on multivariate analysis.

Conclusions

Standardized peritoneal histology in patients with PM from MAT predicts PFS and patients with low-grade histology can be further discriminated by CEA and CC score.

     

Stem cell markers (cytokeratin 15, CD34 and nestin) in primary scarring and nonscarring alopecia

Background  Although the pathogenesis of most primary scarring alopecias is poorly understood, recent studies implicate the bulge region as a possible target.
Objectives  To corroborate these results, we ascertained involvement of follicular bulge stem cells using a panel of antibodies that putatively targeted the same.
Methods  Antibodies used included anticytokeratin (CK) 15, CD34 and nestin on vertical and horizontal tissue sections of 50 cases of scarring and 34 cases of nonscarring alopecia.
Results  Comparing expression of these markers in scarring vs. nonscarring alopecia, CK15 was noted in the follicular bulge region in 23 of 43 (53%) vs. 27 of 27 (100%) cases and in the peripheral layer of the outer root sheath (ORS) (upper two-thirds of the follicle) in 50 of 50 (100%) vs. 34 of 34 (100%) cases; CD34 was noted in the peripheral layer of the ORS (below pilar muscle attachment) in 24 of 35 (69%) vs. 18 of 18 (100%) cases; and nestin was noted in the infundibular region in 18 of 46 (39%) vs. seven of 32 (22%) cases and in the inner aspect of the ORS (below pilar muscle attachment) in eight of 31 (26%) vs. 23 of 23 (100%) cases.
Conclusions  Our findings of differential follicular localization of stem cells underscore follicular progenitor cell heterogeneity and suggest the target in scarring alopecia is not merely follicular bulge stem cells but involves stem cells in the inner and outer aspect of the ORS. Enhanced expression of nestin in the infundibular region in scarring alopecia indicates availability of an accessible, in vivo niche of potential utility as an autologous source of stem cells for therapeutic application.     

Human Antigen and Enzyme Markers in Man-Chinese Hamster Somatic Cell Hybrids: Evidence for Synteny Between the HL-A, PGM3, ME1, and IPO-B Loci

In man-Chinese hamster somatic cell hybrids the segregation of the loci for 27 human enzyme markers and the species-specific surface antigens, including the HL-A histocompatibility antigens, was studied. The results show a synteny of the human loci for phosphoglucomutase 3, cytoplasmic malic enzyme, tetrameric indophenol oxidase, and HL-A. Furthermore, evidence is presented that the loci for the human species-specific antigens are distributed over several chromosomes.     

Glioblastoma and malignant melanoma: Serendipitous or anticipated association?

We describe a patient who had primary glioblastoma (GB) and malignant melanoma (MM). A 78‐year‐old man presented with several weeks to months of history of gait disturbance, confusion, memory disturbance, and worsening speech. Imaging studies performed on admission revealed a large frontotemporal lobe mass associated with the surrounding zone of vasogenic edema. Given the patient's medical history of incomplete biopsy of a midback tumor performed three weeks before, the presumptive clinical diagnosis was metastatic MM. Pathological examination of frozen sections of fragmented specimens obtained at stereotactic biopsy performed on admission revealed a high‐grade malignant neoplasm characterized by discohesive cells in a blue myxoid background and abundant foci of tumor necrosis. Given these features, in conjunction with the abovementioned pathological report, the frozen section diagnosis by the neuropathologist was “neoplasm identified, favor melanoma.” Due to the paucity of lesional tissue, a limited immunohistochemistry performed on the permanent sections revealed positive staining of lesional cells for Sox10 alone using a multiplex MART1/Sox10 immunostain and S‐100 protein, an immunohistochemical profile supporting the presumptive frozen section diagnosis. A tumor debulk procedure, performed two weeks later, revealed histopathologic features most compatible with GB, IDH wild‐type. Thus, additional immunohistochemistry on the permanent sections revealed positive staining of glial fibrillary acidic protein (GFAP), Sox10, and S‐100 protein as well as negative staining of gp100, a complex carbohydrate matrix protein in embryonic melanosomes, using a specific antibody HMB45. The concomitant occurrence of MM and GB in our patient underscores the association between these two entities. Our literature review suggests that the sporadic co‐occurrence of these two conditions is likely not serendipitous.     

Reactivation of type 1 herpes simplex virus and varicella zoster virus in an immunosuppressed patient with acute peripheral facial weakness

We describe a 26-year-old man treated with azathioprine for myasthenia gravis who developed acute left-sided peripheral facial weakness. Brain magnetic resonance imaging (MRI) revealed enhancement in the left geniculate ganglion and in the intracanalicular and tympanic segments of the facial nerve. Analysis of cerebrospinal fluid (CSF) and serum revealed intrathecal synthesis of anti-varicella zoster virus (VZV) IgG antibody. Although previous analyses of saliva, blood mononuclear cells, serum antibodies, middle ear fluid, and auricular and geniculate zone skin scrapings have shown that a small but definite proportion of patients with idiopathic peripheral facial palsy ("Bell's palsy") have the Ramsay Hunt syndrome zoster sine herpete (RHS ZSH), this is the first confirmation of RHS ZSH by intrathecal synthesis of anti-VZV IgG antibody. In addition, herpes simplex virus (HSV)-1 DNA was found in saliva of the patient on 3 consecutive days. Simultaneous reactivation of two alphaherpesviruses (HSV-1 and VZV) in our immunosuppressed patient underscores the need to consider opportunistic infection as a cause of facial weakness.