Despite their rarity in incidence and prevalence, gastrointestinal stromal tumors (GISTs) have emerged as a distinct and noteworthy pathogenetic entity. The clinical management of GISTs has rapidly evolved due to the recent elucidation of their oncogenic signal transduction pathway and the introduction of molecular-targeted therapies. Successful management of GISTs requires a multidisciplinary approach firmly based on an accurate histopathologic diagnosis. In 2007, the Korean GIST study group published the first guideline for optimal diagnosis and treatment of GISTs in Korea. The second version of the guideline was published in 2010. Herein, we provide the results of relevant clinical studies for the purpose of further revision to the guideline. We expect this new guideline will enhance the accuracy of diagnosis, as performed by members of the Korean associate of physicians involved in GIST patient care, thus improving the efficacy of treatment.

Synovial sarcoma arises in the para-articular tissues, and it can also occur in various unexpected sites. We report a rare case of primary monophasic synovial sarcoma (MSS) arising in the mesentery. A 59-year-old man presented with a palpable abdominal mass. On microscopic examination, the entire tumor comprised a dense proliferation of the spindle cells without epithelial components. The tumor cells were positive for transducin-like enhancer of split 1, bcl-2, epithelial membrane antigen and CD99 but negative for CD34, CD117, alpha-smooth muscle actin, cytokeratin, and calretinin on immunohistochemistry. The reverse transcriptase-polymerase chain reaction revealed a single 151-bp fragment representing the SYT-SSX2 fusion transcript. Because mesenteric MSS is extremely rare and many cases display histologic findings that overlap with those of more frequently involved tumors such as hemangiopericytoma and gastrointestinal stromal tumor, there is a chance of making an incorrect diagnosis that can result in an inappropriate treatment.

Precursor B-cell lymphoblastic lymphoma (B-LBL) is an uncommon high-grade neoplasm of immature B cells. It occurs predominantly in childhood with extranodal involvement such as skin and bone. Therefore, primary cutaneous involvement in elderly adults is a very rare manifestation of B-LBL. Here, we report a 78-year-old man with B-LBL presenting as a single cutaneous lesion which was immunohistochemically positive for leukocyte common antigen (LCA), CD79a, paired box 5 (PAX5), B cell lymphoma-2 (bcl-2), and terminal deoxynucleotidyl transferase (TdT) staining, but was without systemic involvement. The patient was treated using cyclophosphamide, adriamycin, vincristine, and prednisolone (CHOP), and achieved complete response (CR) at the first response assessment conducted after 3 CHOP cycles. After an additional cycle of CHOP treatment, radiotherapy was administered at a total dose of 3,600 cGy over 4 weeks. At the 21-month follow-up, he had maintained CR.

Background

Primary intestinal non-Hodgkin lymphoma (NHL) is a heterogeneous disease with regard to anatomic and histologic distribution. Thus, analyses focusing on primary intestinal NHL with large number of patients are warranted.

Methods

We retrospectively analyzed 581 patients from 16 hospitals in Korea for primary intestinal NHL in this retrospective analysis. We compared clinical features and treatment outcomes according to the anatomic site of involvement and histologic subtypes.

Results

B-cell lymphoma (n = 504, 86.7%) was more frequent than T-cell lymphoma (n = 77, 13.3%). Diffuse large B-cell lymphoma (DLBCL) was the most common subtype (n = 386, 66.4%), and extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) was the second most common subtype (n = 61, 10.5%). B-cell lymphoma mainly presented as localized disease (Lugano stage I/II) while T-cell lymphomas involved multiple intestinal sites. Thus, T-cell lymphoma had more unfavourable characteristics such as advanced stage at diagnosis, and the 5-year overall survival (OS) rate was significantly lower than B-cell lymphoma (28% versus 71%, P < 0.001). B symptoms were relatively uncommon (20.7%), and bone marrow invasion was a rare event (7.4%). The ileocecal region was the most commonly involved site (39.8%), followed by the small (27.9%) and large intestines (21.5%). Patients underwent surgery showed better OS than patients did not (5-year OS rate 77% versus 57%, P < 0.001). However, this beneficial effect of surgery was only statistically significant in patients with B-cell lymphomas (P < 0.001) not in T-cell lymphomas (P = 0.460). The comparison of survival based on the anatomic site of involvement showed that ileocecal regions had a better 5-year overall survival rate (72%) than other sites in consistent with that ileocecal region had higher proportion of patients with DLBCL who underwent surgery. Age > 60 years, performance status ≥ 2, elevated serum lactate dehydrogenase, Lugano stage IV, presence of B symptoms, and T-cell phenotype were independent prognostic factors for survival.

Conclusions

The survival of patients with ileocecal region involvement was better than that of patients with involvement at other sites, which might be related to histologic distribution, the proportion of tumor stage, and need for surgical resection.

Despite the rarity in incidence and prevalence, gastrointestinal stromal tumor (GIST) has emerged as a distinct pathogenetic entity. And the clinical management of GIST has been evolving very rapidly due to the recent recognition of its oncogenic signal transduction pathway and the introduction of new molecular-targeted therapy. Successful management of GIST requires a multidisciplinary approach firmly based on accurate histopathologic diagnosis. However, there was no standardized guideline for the management of Korean GIST patients. In 2007, the Korean GIST study group (KGSG) published the first guideline for optimal diagnosis and treatment of GIST in Korea. As the second version of the guideline, we herein have updated recent clinical recommendations and reflected changes in diagnosis, surgical and medical treatments for more optimal clinical practice for GIST in Korea. We hope the guideline can be of help in enhancing the quality of diagnosis by members of the Korean associate of physicians involving in GIST patients's care and subsequently in achieving optimal efficacy of treatment.

Background

The breast is a rare extranodal site of non-Hodgkin lymphoma, and primary breast lymphoma (PBL) has been arbitrarily defined as disease localized to one or both breasts with or without regional lymph nodes involvement. The aim of this study was to evaluate the clinical outcomes in patients with diffuse large B cell lymphoma (DLBCL) and breast involvement, and to find the criteria of PBL reflecting the outcome and prognosis.

Methods

We retrospectively analyzed data from 68 patients, newly diagnosed with DLBCL and breast involvement at 16 Korean institutions between January 1994 and June 2009.

Results

Median age at diagnosis was 48 years (range, 20-83 years). Forty-three (63.2%) patients were PBL according to previous arbitrary criteria, sixteen (23.5%) patients were high-intermediate to high risk of international prognostic index. The patients with one extranodal disease in the breast (OED) with or without nodal disease were 49 (72.1%), and those with multiple extranodal disease (MED) were 19 (27.9%). During median follow-up of 41.5 months (range, 2.4-186.0 months), estimated 5-year progression-free survival (PFS) was 53.7 ± 7.6%, and overall survival (OS) was 60.3 ± 7.2%. The 5-year PFS and OS was significantly higher for patients with the OED group than those with the MED group (5-year PFS, 64.9 ± 8.9% vs. 27.5 ± 11.4%, p = 0.001; 5-year OS, 74.3 ± 7.6% vs. 24.5 ± 13.0%, p < 0.001). In multivariate analysis, MED (hazard ratio [HR], 3.61; 95% confidence interval [CI], 1.07-12.2) and fewer than four cycles of systemic chemotherapy with or without local treatments (HR, 4.47; 95% CI, 1.54-12.96) were independent prognostic factors for worse OS. Twenty-five (36.8%) patients experienced progression, and the cumulative incidence of progression in multiple extranodal sites or other than breasts and central nervous system was significantly different between the OED group and the MED group (5-year cumulative incidence, 9.7 ± 5.4% vs. 49.0 ± 15.1%, p = 0.001).

Conclusions

Our results show that the patients included in OED group, reflecting different treatment outcome, prognosis and pattern of progression, should be considered as PBL in the future trial. Further studies are warranted to validate our suggested criteria.

Primary gastric choriocarcinoma (PGC) is a rare tumor, and its pathogenesis is still uncertain. Most PGCs have been reported to possess an adenocarcinoma component of variable extent, and pure PGC is especially rare. The diagnosis of PGC is confirmed by exhibition of choriocarcinomatous components on biopsy and exhibition of β-hCG positive cell on immunohistochemical stain and elevation of the serum β-hCG. Moreover it must be confirmed that no other site including gonads displays any tumor masses. The PGC tends to be more invasive and to have early metastasis. The median survival is known to be less than several months. We report two cases. The first case was a 62 year-old man who was diagnosed as advanced gastric cancer (AGC) by endoscopic biopsy with hepatic metasasis and received palliative chemotherapy with modified FOLFOX regimen and Genexol plus cisplatin regimen. He underwent subtotal gastrectomy due to perforation of the stomach during chemotherapy. On post-operative biopsy, He was re-diagnosed as PGC and received another palliative chemotherapy modified FOLFIRI, BEP, EMACO, VIP. However, multiple liver metastases were aggravated, and also serum AFP level increased. Ultimately, the paient died 10 months after initial diagnosis. Another case was a 45 year-old man. On endoscopic biopsy, he was diagnosed as AGC of adenocarcinoma. On Chest and Abdomen CT, multiple pulmonary and hepatic metastasis were also confirmed. On liver biopsy, He was diagnosed as PGC. The immunohistochemical stains were performed and the results were cytokeratin positive, EMA negative and β-hCG weak positive. The serum β-hCG level was highly elevated. BEP, VIP and EMA/CO combination therapy were administered, but he died at 12th months after the initial diagnosis.

We report a gastrointestinal stromal tumor (GIST) patient with male gynecomastia and testicular hydrocele after treatment with imatinib mesylate. A 42 yr-old male patient presented for management of hepatic masses. Two years earlier, he had undergone a small bowel resection to remove an intraabdominal mass later shown to be a GIST, followed by adjuvant radiation therapy. At presentation, CT scan revealed multiple hepatic masses, which were compatible with metastatic GIST, and he was prescribed imatinib 400 mg/day. During treatment, he experienced painful enlargement of the left breast and scrotal swelling. Three months after cessation of imatinib treatment, the tumors recurred, and, upon recommencing imatinib, he experienced painful enlargement of the right breast and scrotal swelling. He was diagnosed with male gynecomastia caused by decreased testosterone and non-communicative testicular hydrocele. He was given androgen support and a hydrocelectomy, which improved his gynecomastia. The mechanism by which imatinib induces gynecomastia and hydrocele is thought to be associated with an inhibition of c-KIT and platelet-derive growth factor. This is the first report, to our knowledge, describing concurrent male gynecomastia and testicular hydrocele after imatinib treatment of a patient with GIST.

Purpose

The benefit of high-dose chemotherapy (HDC) for metastatic breast cancer (MBC) is controversial. We evaluated the efficacy and safety of HDC with cyclophosphamide, thiotepa, and carboplatin (CTCb) followed by autologous stem-cell transplantation (ASCT) for MBC patients.

Materials and Methods

From September 1994 to December 1999, 23 MBC patients were enrolled. All the patients received 2 to 10 cycles of induction chemotherapy. Before transplantation, 12 patients were in complete response (CR), nine were in partial response (PR), and two had progressive disease (PD). The HDC regimen consisted of cyclophosphamide 1,500 mg/m2/day, thiotepa 125 mg/m2/day and carboplatin 200 mg/m2/day intravenously for 4 consecutive days.

Results

After ASCT, 13 patients (56%) had a CR, five (22%) had a PR, three (13%) had no change, while two (9%) showed a PD. Seventeen patients relapsed or progressed during the median follow-up of 78 months. The median progression-free survival (PFS) time was 11 months and the median overall survival (OS) time was 23 months. The 5-year PFS and OS rates were 22% and 25%, respectively. On the multivariate analyses, less than 4 involved lymph nodes was predictive of a better PFS and OS.

Conclusion

HDC with CTCb for MBC has acceptable toxicity; however, this treatment does not show a survival benefit.

Background

This study evaluates the effectiveness of immunochemotherapy and radiation therapy in the treatment of patients with primary bone lymphoma (PBL).

Methods

We retrospectively reviewed the medical records of 33 patients with PBL who were treated at 6 medical centers in Korea from 1992 to 2010. Clinicopathological features and treatment outcomes were analyzed.

Results

The median age of the patients participating in our study was 40 years. The most common sites of involvement were the pelvis (12.36%) and femur (11.33%). CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) or CHOP-like regimens were administered to 20 patients (61%), and R-CHOP (rituximab plus CHOP) was administered to the remaining 13 patients (39%). The overall response rate was 89% (complete response, 76%; partial response, 12%). The overall survival (OS) of patients with solitary bone lesions was longer than that of patients with multiple bone lesions (median OS: not reached vs. 166 months, respectively; P=0.089). Addition of rituximab to CHOP did not significantly affect either OS or progression-free survival (P=0.53 and P=0.23, respectively). Combining radiation therapy with chemotherapy also did not improve the OS or progression-free survival of patients with solitary bone lesions.

Conclusion

Conventional cytotoxic chemotherapy remains an effective treatment option for patients with PBL. Additional benefits of supplementing chemotherapy with either rituximab or radiation therapy were not observed in this study. Further investigation is needed to characterize the role of immunochemotherapy in treating patients with PBL.