Postoperative radiation therapy for extramammary Paget's disease.

BACKGROUND: Extramammary Paget's disease (EMPD) is a rare cutaneous malignancy that is usually treated with surgery. Patients with positive surgical margins require adjuvant therapy, but there have been few reports on the use of radiation therapy. OBJECTIVES: To investigate the effectiveness of postoperative radiation therapy in EMPD. MATERIALS AND METHODS: Twenty-one patients with EMPD involving the genitalia underwent radiation therapy as adjuvant therapy after surgery. Ten patients had inguinal lymph node involvement before radiation therapy, but none had distant metastases. A median total dose of 59·4 Gy (range, 45-64·8 Gy) was delivered to the tumour bed in 30 fractions (range, 23-36 fractions). RESULTS: At a median follow-up period of 38 months, all patients had local control. However, six patients had developed distant metastases 6-43 months after radiation therapy. The distant metastasis-free rates were 66% at 3 years and 55% at 5 years. Inguinal lymph node involvement was a significant risk factor for distant metastases. Four patients died 33-58 months after irradiation; the causes of death were tumour progression in three patients and infectious pneumonia in one. The overall and cause-specific survival rates were both 92% at 3 years, and 62% and 71% at 5 years, respectively. No therapy-related toxicities of grade ≥ 3 were observed. CONCLUSIONS: Postoperative radiation therapy is safe and effective in maintaining local control in patients with EMPD.

Radiation therapy for extramammary Paget's disease: treatment outcomes and prognostic factors.

BACKGROUND: Extramammary Paget's disease (EMPD) is a relatively rare malignancy, and there are few reports related to radiation therapy. In the present study, we investigated the outcome of radiation therapy for EMPD. PATIENTS AND METHODS: Forty-one patients with EMPD in the genitalia underwent radiation therapy with curative intent. Fifteen patients had regional lymph node metastases before radiation therapy, but none had distant metastasis. Total doses of 45-80.2 Gy (median, 60 Gy) were delivered to tumor sites in 23-43 fractions (median, 33 fractions). RESULTS: At a median follow-up period of 41 months, 16 patients had developed recurrences, including 5 with local progression within the radiation field and 12 with lymph node or/and distant metastases outside the radiation field. The local progression-free and disease-free rates were 88% and 55% at 3 years, and 82% and 46% at 5 years, respectively. Nine patients died at 6-73 months after irradiation; the causes of death were tumor progression in five patients, infectious pneumonia in two, renal failure in one and old age in one. The overall and cause-specific survival rates were 93% and 96% at 3 years, and 68% and 84% at 5 years, respectively. Tumor invasion into the dermis and regional lymph node metastasis were significant prognostic factors for both distant metastasis and survival. No therapy-related toxicities of grade ≥3 were observed. CONCLUSIONS: Radiation therapy is safe and effective for patients with EMPD. It appeared to contribute to prolonged survival owing to good tumor control, and to be a promising curative treatment option.

Radiation therapy with concurrent retrograde superselective intra-arterial chemotherapy for gingival carcinoma.

PURPOSE: The aim of this study was to review the efficacy and toxicity of radiation therapy with concurrent retrograde superselective intra-arterial chemotherapy in the treatment of gingival carcinoma. METHODS AND MATERIALS: In all, 34 patients (21 men and 13 women) with squamous cell carcinoma of the gingiva underwent radiation therapy with concurrent retrograde superselective intra-arterial chemotherapy. Treatment consisted of daily external irradiation and concurrent retrograde superselective intra-arterial infusion with cisplatin and docetaxel. A median total dose of 60 Gy in 30 fractions was delivered to tumors. RESULTS: Of the 34 patients, 29 (85 %) achieved a complete response (CR) and 5 had residual tumors. Of the 29 patients with a CR, 2 had local recurrences and 1 had distant metastasis 1-15 months after treatment. Twenty-six of the 36 patients had survived at a median follow-up time of 36 months (range 12-79 months); 4 died of cancer and 4 died of non-cancer-related causes. At both 3 and 5 years after treatment, the overall survival rates were 79 % and the cause-specific survival rates were 85 %. Osteoradionecrosis of the mandibular bone only developed in 1 patient after treatment. CONCLUSION: Radiation therapy with concurrent retrograde superselective intra-arterial chemotherapy was effective and safe in the treatment of gingival carcinoma. This treatment may be a promising curative and organ-preserving treatment option for gingival carcinoma.

Radiation therapy for lymph node metastasis from extramammary Paget's disease.

BACKGROUND: Inoperable patients with lymph node metastasis from extramammary Paget's disease (EMPD) have limited curative treatment options. OBJECTIVE: The aim of this study was to review the efficacy and toxicity of radiation therapy for lymph node metastasis from EMPD. METHODS: Eight EMPD patients with pelvic and inguinal lymph node metastasis, representing a total of 43 metastatic lymph nodes, underwent radiation therapy. Of these eight patients, two received radiation therapy as an initial treatment for EMPD and six for recurrence only in the lymph nodes after they had undergone surgery. Total doses of 45-61.2 Gy (median, 59.4 Gy) were delivered to metastatic lymph nodes in 25-34 fractions (median, 33 fractions). RESULTS: Of the 43 metastatic lymph nodes in the eight patients, all but one had no progression at the median follow-up time of 22 months. The 2-year local control rates were 86% in all patients and 98% in all metastatic lymph nodes, respectively. No therapy-related toxicities of grade 3 or greater were observed. CONCLUSION: Radiation therapy is effective and safe, and appears to offer a curative treatment option for lymph node metastasis from EMPD.

Efficacy and toxicity of (chemo)radiotherapy for primary subglottic cancer.

BACKGROUND AND PURPOSE: Primary subglottic cancer is a rare malignancy. We investigated the efficacy and toxicity of radiotherapy for subglottic cancer. PATIENTS AND METHODS: Nineteen patients with primary squamous cell carcinoma of the subglottis received radiotherapy, 14 of whom also underwent chemotherapy. Of the 19 patients, 15 received definitive radiotherapy to the gross tumors with total doses of 70-70.2 Gy in 35-39 fractions, and 4 underwent preoperative radiotherapy with total doses of 37.8-55.8 Gy in 21-31 fractions, followed by total laryngectomy. RESULTS: Of the 19 patients, 5 developed local progression and 2 developed distant metastasis at the median follow-up period of 5 years. The 5-year local control and disease-free rates were 74 and 63%, respectively. Three patients died of tumor progression, and the 5-year overall and disease-free survival rates were 80 and 63%, respectively. Regarding acute toxicities, transient mucositis and dermatitis of grade 3 or lower were observed in all patients, but there were no late toxicities of grade 3 or higher. CONCLUSION: Radiotherapy is a safe and effective treatment for patients with primary squamous cell carcinoma of the subglottis. The use of chemotherapy together with radiotherapy may enhance treatment efficacy and contribute to larynx preservation through good local control.

Radiation therapy for primary carcinoma of the eyelid: tumor control and visual function.

BACKGROUND AND PURPOSE: Surgical excision remains the standard and most reliable curative treatment for eyelid carcinoma, but frequently causes functional and cosmetic impairment of the eyelid. We therefore investigated the efficacy and safety of radiation therapy in eyelid carcinoma. PATIENTS AND METHODS: Twenty-three patients with primary carcinoma of the eyelid underwent radiation therapy. Sebaceous carcinoma was histologically confirmed in 16 patients, squamous cell carcinoma in 6, and basal cell carcinoma in 1. A total dose of 50-66.6 Gy (median, 60 Gy) was delivered to tumor sites in 18-37 fractions (median, 30 fractions). RESULTS: All but 3 of the 23 patients had survived at a median follow-up period of 49 months. The overall survival and local progression-free rates were 87% and 93% at 2 years, and 80% and 93% at 5 years, respectively. Although radiation-induced cataracts developed in 3 patients, visual acuity in the other patients was relatively well preserved. There were no other therapy-related toxicities of grade 3 or greater. CONCLUSION: Radiation therapy is safe and effective for patients with primary carcinoma of the eyelid. It appears to contribute to prolonged survival as a result of good tumor control, and it also facilitates functional and cosmetic preservation of the eyelid.

Production of refractory dissolved organic matter by bacteria.

Most of the oceanic reservoir of dissolved organic matter (DOM) is of marine origin and is resistant to microbial oxidation, but little is known about the mechanisms of its formation. In a laboratory study, natural assemblages of marine bacteria rapidly (in <48 hours) utilized labile compounds (glucose, glutamate) and produced refractory DOM that persisted for more than a year. Only 10 to 15% of the bacterially derived DOM was identified as hydrolyzable amino acids and sugars, a feature consistent with marine DOM. These results suggest that microbial processes alter the molecular structure of DOM, making it resistant to further degradation and thereby preserving fixed carbon in the ocean.

Direct determination of carbon and nitrogen contents of natural bacterial assemblages in marine environments

In order to better estimate bacterial biomass in marine environments, we developed a novel technique for direct measurement of carbon and nitrogen contents of natural bacterial assemblages. Bacterial cells were separated from phytoplankton and detritus with glass fiber and membrane filters (pore size, 0.8 &mgr;m) and then concentrated by tangential flow filtration. The concentrate was used for the determination of amounts of organic carbon and nitrogen by a high-temperature catalytic oxidation method, and after it was stained with 4',6-diamidino-2-phenylindole, cell abundance was determined by epifluorescence microscopy. We found that the average contents of carbon and nitrogen for oceanic bacterial assemblages were 12.4 +/- 6.3 and 2.1 +/- 1.1 fg cell-1 (mean +/- standard deviation; n = 6), respectively. Corresponding values for coastal bacterial assemblages were 30.2 +/- 12.3 fg of C cell-1 and 5.8 +/- 1.5 fg of N cell-1 (n = 5), significantly higher than those for oceanic bacteria (two-tailed Student's t test; P < 0.03). There was no significant difference (P > 0.2) in the bacterial C:N ratio (atom atom-1) between oceanic (6.8 +/- 1.2) and coastal (5.9 +/- 1.1) assemblages. Our estimates support the previous proposition that bacteria contribute substantially to total biomass in marine environments, but they also suggest that the use of a single conversion factor for diverse marine environments can lead to large errors in assessing the role of bacteria in food webs and biogeochemical cycles. The use of a factor, 20 fg of C cell-1, which has been widely adopted in recent studies may result in the overestimation (by as much as 330%) of bacterial biomass in open oceans and in the underestimation (by as much as 40%) of bacterial biomass in coastal environments.

Validity of positron emission tomography using fluoro-2-deoxyglucose for the preoperative evaluation of endometrial cancer.

To clarify the validity of positron emission tomography using fluoro-2-deoxyglucose (FDG-PET) for the preoperative evaluation of endometrial cancer, we analyzed the preoperative FDG-PET images of both primary and metastatic lesions of 30 patients with endometrial cancer, and compared them with computed tomography (CT) and/or magnetic resonance imaging (MRI) images and the results of postoperative pathologic findings. As to the primary lesions, FDG-PET could easily identify the cancer, and the sensitivity was 96.7%, which tended to be higher than that of 83.3% by CT/MRI. As to the evaluation of retroperitoneal lymph node metastasis, FDG-PET could detect none of five cases of lymph node metastatic lesions of up to 0.6 cm in diameter but had higher specificity (100%) compared with CT/MRI (85.7%). The sensitivity of FDG-PET for detection of extrauterine lesions excluding retroperitoneal lymph nodes was 83.3% and was superior to that of CT/MRI (66.7%), although there was no difference in the specificity between the modalities (100%). The diagnostic ability of FDG-PET was limited if used alone, but FDG-PET gave additional information especially with regard to the extrauterine lesions whose significance could not be determined on CT/MRI. However, we also found that FDG-PET could not identify any lymph node metastasis less than 1 cm in diameter; therefore, a negative finding of lymph node metastasis on FDG-PET should not be interpreted as a reason for omitting retroperitoneal lymph node dissection for the precise surgical staging of endometrial cancer.