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March 2002
A marker for renal cell
carcinoma
An immunohistochemical marker for distinguishing among the different
subtypes of renal cell carcinoma and separating metastatic renal cell
carcinoma from its mimics would be useful in difficult cases. The
authors tested the diagnostic use of the monoclonal antibody renal
cell carcinoma marker (RCC Ma) against a normal proximal tubular brush
border antigen. They performed immunostaining using RCC Ma and the
avidin-biotin-peroxidase complex technique on archival tissues from
primary and metastatic tumors of renal and nonrenal origin. RCC Ma
stained 67 percent (42 of 63) of metastatic renal cell carcinomas
and only two percent (two of 108) of nonrenal metastases, both of
which were metastatic breast carcinomas. RCC Ma also marked 15 of
146 nonrenal primary tumors. Among the 15 positive cases were tumors
from the breast, thyroid, and testis. Notable nonstaining tumors included
adrenal (zero of 13), lung (zero of four), and liver (zero of 21)
primaries. Among primary renal tumors, 79.7 percent (122 of 153) were
positive, including clear cell (84 percent), papillary (96 percent),
chromophobe (45 percent), and sarcomatoid (25 percent). Collecting
duct carcinoma (zero of five) and oncocytoma (zero of 15) were negative.
Interestingly, 72 percent of primary renal cell carcinomas had more
than 50 percent of positive tumor cells, in contrast to only 57 percent
of metastatic renal cell carcinomas. The authors stated that RCC Ma
is an excellent marker for primary renal cell carcinoma. And although
RCC Ma is highly specific for metastatic renal cell carcinoma, a negative
result may not rule out metastatic renal cell carcinoma because of
low sensitivity and a focal staining pattern in some positive cases.
McGregor DK, Khurana KK, Cao C, et al. Diagnosing primary and
metastatic renal cell carcinoma: the use of the monoclonal antibody
“renal cell carcinoma marker”. Am J Surg Pathol. 2001;25:1485-1492.
Reprints: Dr. Luan D. Truong, Dept. of Pathology, MS 205, Methodist
Hospital, 6565 Fannin St., Houston, TX 77030; ltruong@bcm.tmc.edu
Comparison of techniques
to detect cervical neoplasia
The cost-effectiveness of different methods for screening for clinically
significant cervical disease varies. The authors compared several
methods for cervical cancer screening in a study involving 1,997 women
between the ages of 35 and 45 from rural Shanxi Province, China. Each
woman underwent a self-test for intermediate/high-risk human papillomavirus,
a direct test for HPV, fluorescence spectroscopy, liquid-based Pap
(read manually and by computer), visual inspection diagnosis, and
colposcopy with multiple cervical biopsies. The sensitivity and specificity
for the detection of >CIN II were 83 percent and 86 percent,
respectively, for the HPV self-test, 95 percent and 85 percent for
the HPV direct test, 94 percent and 78 percent for the ThinPrep Pap
(>ASCUS), 77 percent and 98 percent for the ThinPrep Pap (>HGSIL),
94 percent and nine percent for fluorescence spectroscopy, 71 percent
and 74 percent for visual inspection, and 81 percent and 77 percent
for colposcopy. The authors concluded that, based on these data and
the existing health care infrastructure in China, further refinement
of primary HPV screening using centralized labs is necessary. Self-testing
may be effective in local villages if the devices and techniques employed
are improved.
Belinson J, Qiao YL, Pretorius R, et al. Shanxi Province cervical
cancer screening study: a cross-sectional comparative trial of multiple
techniques to detect cervical neoplasia. Gynecol Oncol. 2001;83:439-444.
Reprints: Dr. J. Belinson, Cleveland Clinic Foundation, 9500 Euclid
Ave., A-81, Cleveland, OH 44195; belinsj@ccf.org
Predicting behavior of gastric
MALT lymphoma
The natural history of low-grade marginal zone B-cell lymphoma of
mucosa-associated lymphoid tissue (MALT) of the stomach is variable.
Approximately half of patients respond to antibiotic therapy for Helicobacter
pylori. Among those who do not respond to antibiotics are some
patients with stable disease which does not progress beyond the indolent
low-grade stage. A second group, however, progresses to more aggressive
large-cell lymphoma. The ability to predict which patient with persistent
disease is likely to have a tumor that behaves in an aggressive fashion
has obvious clinical implications. The authors employed microsatellite
screening in 24 gastric MALT lymphomas. This was compared with similar
analyses in cases of diffuse large B-cell lymphoma of the stomach.
Of the 10 cases that showed a t(11;18) translocation, only one showed
the presence of other genetic alterations, and none demonstrated transformation
to large-cell lymphoma. In contrast, the t(11;18)-negative lymphomas
showed numerous allelic imbalances—some of them identical with
aberrations seen in high-grade diffuse large B-cell lymphoma (DLBCL)—suggesting
that this group is the source of tumors eventually transforming into
high-grade DLBCL. The most common of these abnormalities was amplification
of 3q26.2-27, which harbors the locus of the BCL6 gene.
Starostik
P, Patzner J, Greiner A, et al. Gastric marginal zone B-cell lymphomas
of MALT type develop along two distinct pathogenetic pathways. Blood.
2002;99:3-9.
Reprints: Petr Starostik, Institute of Pathology, Wurzburg University,
Luitpoldkrankenhaus, Josef-Strasse 2, D-97080 Wurzburg, Germany;
petr.starostik@mail.uni-wuerzburg.de
Ovarian mucinous carcinoid
tumors
One rarely encounters a primary ovarian mucinous (goblet cell) carcinoid
tumor. The clinicopathologic features of a series of these tumors
has not been previously described. In this study, the authors presented
17 examples of primary ovarian mucinous carcinoids from patients aged
14 to 74 years (tumor size, 0.8 to 30 cm), excluding cases with minor
foci seen in other types of primary ovarian tumors. None of these
were associated with the carcinoid syndrome. All tumors were positive,
in varying proportions, for one or more neuroendocrine markers. In
six cases, the tumor was located in the wall of a mature cystic teratoma.
Other associated primary ovarian neoplasms were mucinous cystadenocarcinoma
(three of 17), mucinous cystic borderline tumor (one of 17), borderline
Brenner tumor (one of 17), and epidermoid cyst (one of 17). The authors
subclassified the ovarian mucinous carcinoids into three groups based
on microscopic features: well-differentiated, atypical, and carcinoma
arising in mucinous carcinoid (to avoid confusion with a collision
tumor, such as a mucinous cystadenocarcinoma extrinsic to the ovarian
mucinous carcinoid). The only stage II and III tumors were two carcinomas
arising in mucinous carcinoids, and these were found in the only patients
to die from the disease. The authors also presented features that
help distinguish these tumors from mucinous carcinoids metastatic
to the ovary, Krukenberg tumors (which were evaluated for the expression
of neuroendocrine markers in this study and were positive in seven
of 10 cases), primary ovarian carcinoids, including strumal carcinoids,
mucinous cystic tumors with neuroendocrine cells, and neuroendocrine
carcinomas of the small or nonsmall-cell type.
Baker PM, Olivia E, Young RH, et al. Ovarian mucinous carcinoids
including some with a carcinomatous component. Am J Surg Pathol.
2001;25:557-568.
Reprints: Dr. Esther Olivia, Dept. of Pathology, Massachusetts
General Hospital, 55 Fruit St., Boston, MA 02114
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