LWBK1006-19 LWW-Govindan-Review December 7, 2011 21:24
228 DeVita, Hellman, and Rosenberg’s CANCER: Principles and Practice of Oncology Reviewradiotherapy, the relatively low rates of recurrence after radiotherapy
and the high cure rates associated with salvage chemotherapy, systemic
treatment is not recommended for patients with localized disease.Answer 19.17. The answer is B.
A number of hematologic malignancies have been reported in associa-
tion with mediastinal NSGCT, including acute megakaryocytic leukemia,
acute myeloid leukemia, erythroleukemia, malignant histiocytosis, and
myelodysplastic syndromes. These may be diagnosed either before or at
the same time as the NSGCT. Solid tumors may also occur at an increased
frequency in patients with mediastinal germ cell tumors. In addition,
mediastinal NSGCTs have a propensity to develop malignant non-germ
cell components, such as adenocarcinoma, squamous cell carcinoma, and
sarcoma.Answer 19.18. The answer is D.
This man presents with locally advanced mediastinal seminoma that
invades adjacent structures and involves regional lymph nodes. More than
half of patients with mediastinal seminoma will have metastases at diag-
nosis, primarily to the intrathoracic lymph nodes, lung, or bone. Patients
with locally advanced disease are usually treated with cisplatin-based
chemotherapy with or without radiotherapy, whereas those with distant
disease are treated with chemotherapy alone. Cisplatin-based treatment
has been reported to result in an objective response rate that approaches
95% and a complete response rate of up to 85%, with a long-term disease-
free survival rate of 80% to 85%. Carboplatin-based therapy is known
to be inferior to cisplatin-based regimens. For patients with bulky, locally
advanced mediastinal seminoma, the large radiation fields required to
encompass all disease can result in excessive pulmonary or cardiac tox-
icity. In addition, despite high rates of local control, 20% to 40% of
patients with locally advanced disease who are treated with radiotherapy
alone will develop distant metastases, leading to the recommendation for
primary systemic chemotherapy in such patients. Surgery is not indicated
in the primary treatment of mediastinal seminoma.Answer 19.19. The answer is A.
This man has had an excellent response to initial chemotherapy for locally
advanced mediastinal seminoma with normalization of-HCG and a
small residual mediastinal mass. The optimal management of patients
with a residual mass on radiographic follow-up after treatment with ini-
tial chemotherapy or radiotherapy for seminoma remains controversial.
Most studies have demonstrated that viable seminoma is rare in resected
residual masses, and that 85% to 90% of such specimens consist entirely
of scar tissue. Other studies have shown that up to 25% of residual masses
more than 3 cm in size after initial chemotherapy contain viable semi-
noma. Nevertheless, resection of a residual mass is currently not recom-
mended unless the mass enlarges during clinical surveillance. Similarly,
the addition of radiotherapy after chemotherapy has not been shown to