Axillary lymph node characteristics in breast cancer patients versus post-COVID-19 vaccination: Overview of current evidence per imaging modality.

BACKGROUND: Axillary lymph node characteristics on axillary ultrasound (US), breast MRI and 18F-FDG PET/CT are relevant at breast cancer diagnosis. Axillary lymphadenopathy after COVID-19 vaccination has been frequently reported. This may cause a diagnostic dilemma, particularly in the ipsilateral axilla in women who have a either a recent diagnosis of breast cancer or a history of breast cancer. This review provides an overview of the current evidence regarding axillary lymph node characteristics at breast cancer diagnosis versus "post-COVID-19 vaccination". METHODS: A non-systematic narrative review was performed. Studies describing axillary lymph node characteristics per imaging modality (axillary US, breast MRI and 18F-FDG PET/CT) in breast cancer patients versus post-COVID-19 vaccination were selected and used for the current study. RESULTS: The morphologic characteristics and distribution of abnormal nodes on US may differ from the appearance of metastatic adenopathy since diffuse cortical thickening of the lymph nodes is the most observed characteristic after vaccination, whereas metastases show as most suspicious characteristics focal cortical thickening and effacement of the fatty hilum. Current evidence on MRI and 18F-FDG on morphologic characteristics of axillary lymphadenopathy is missing, although it was suggested that vaccine related lymphadenopathy is more likely to be present in level 2 and 3 nodes than metastatic nodes. Reported frequencies of lymphadenopathy post-COVID-19 vaccination range from 49% to 85% (US), 29% (breast MRI) and 14.5% to 53.9% (18F-FDG PET/CT). Several factors may impact the presence or extent of lymphadenopathy post-COVID-19 vaccination: injection site, type of vaccine (i.e., mRNA versus vector), time interval (days) between vaccination and imaging, previous history of COVID-19 pneumonia, and first versus second vaccine dose. CONCLUSION: Although lymph node characteristics differ at breast cancer diagnosis versus post-COVID-19 vaccination, clinical information regarding injection site, vaccine type and vaccination date needs to be documented to improve the interpretation and guide treatment towards the next steps of action.

Unusual thoracic radiographic findings in children treated for Hodgkin's disease.

Mantle irradiation is often part of the treatment for Hodgkin's disease. Localized pneumonitis and fibrosis are well-known sequelae of this treatment. We report nine patients with unusual thoracic radiographic findings following treatment for Hodgkin's disease. All nine had mediastinal widening. Seven of these patients received combined modality therapy in which prednisone was given with their MOPP. In these seven patients, an increase in mediastinal width developed at the same time as the radiographic changes of radiation pneumonitis. Two patients developed bilateral infiltrates extending beyond the field of radiation to the lung periphery. In one of these patients, a spontaneous pneumomediastinum developed. One patient underwent mediastinal biopsy that revealed inflammatory changes similar to those seen in radiation pneumonitis. All patients either responded to steroids or had spontaneous regression of radiographic abnormalities supporting the presumed diagnosis of treatment related changes. Recognition of these unusual sequelae of mantle irradiation will aid in differentiating them from infection or tumor and lead to prompt, appropriate treatment.

The m-BACOD combination chemotherapy regimen in large-cell lymphoma: analysis of the completed trial and comparison with the M-BACOD regimen.

One hundred thirty-four assessable patients with stage II-IV large-cell lymphoma (LCL) were treated with the combination chemotherapy regimen methotrexate with leucovorin, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone (m-BACOD) between July 1981 and May 1986. The m-BACOD regimen substituted moderate-dose methotrexate (200 mg/m2 x 2) for the high-dose methotrexate used in the preceding M-BACOD regimen; all other drugs were administered as with m-BACOD. Eighty-two patients (61%) in the completed m-BACOD trial achieved a complete response (CR). With a median follow-up of 3.6 years, 62 patients (76%) continue in CR. Predicted survivals of 1, 3, and 5 years for the entire m-BACOD group are 80%, 63%, and 60%, respectively, with a 5-year disease-free survival (DFS) of 74% for the patients who achieve CR. The results obtained with m-BACOD are comparable with those obtained in the preceding M-BACOD trial, which now has a median follow-up of 8.0 years. The reduction in methotrexate dosage in m-BACOD patients was not associated with an increased incidence of CNS relapse. Long-term follow-up of the 215 M/m-BACOD patients indicates that the regimens are not associated with an increased incidence of secondary malignancy. Prolonged follow-up also indicates that advanced-stage patients have a persistent rate of late relapse of about 7.0% per year for years 2 to 5 of their follow-up and that stage II patients have an approximate 2.1% per year rate of late relapse. Application of the previously described prognostic factor model to the 215 M/m-BACOD patients from the completed trials identifies a high-risk group of patients with a CR rate and predicted 5-year survival (38% and 24%, respectively) that are significantly worse than those of the group as a whole (65% and 57%, respectively).

Patterns of relapse in large-cell lymphoma patients with bulk disease: implications for the use of adjuvant radiation therapy.

In patients with large-cell lymphoma (LCL) treated with combination chemotherapy, the presence of bulk disease has consistently been associated with a poorer response rate and a shortened survival. The optimal therapy for patients with bulk disease (greater than or equal to 10 cm) will depend on whether treatment failures result from inadequate tumor eradication in prior bulk sites or from distant dissemination. To address this issue, we have evaluated patterns of relapse in patients with bulk disease who relapsed after achieving a complete remission with methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone (M- or m-BACOD). Eighty-one II, III, or IV patients with disease greater than or equal to 10 cm were identified; 45 of the 81 patients achieved a confirmed complete response (CR) and are included in the analysis. The 45 complete responders included 21 patients with localized (stage II) disease and 24 patients with advanced (stage III/IV) disease. Six of the 21 stage II complete responders and three of the 24 stage II/IV complete responders also received adjuvant radiation therapy following completion of M- or m-BACOD. Only one of the 21 patients with stage II disease relapsed, doing so in the site of prior bulk involvement. In contrast, nine of 24 patients with stage III/IV disease relapsed, although no patient failed solely in the site of prior bulk disease. Stage III/IV patients recurred in either a new site (one patient), a new and old site (five), an old non-bulk site (two), or both old non-bulk and bulk sites (one). These results indicate that advanced-stage bulk-disease patients do not consistently relapse in sites of prior bulk disease; therefore, this group of patients is unlikely to benefit from adjuvant radiation therapy administered following completion of combination chemotherapy. Although the low relapse rate and the addition of adjuvant radiation therapy in a subgroup of the stage II bulk-disease patients precludes a definitive analysis, our results further suggest that these patients may be effectively treated with combination chemotherapy alone.

Gallium-67 imaging: a predictor of residual tumor viability and clinical outcome in patients with diffuse large-cell lymphoma.

Durable complete remissions (CRs) can be achieved in patients with diffuse large-cell lymphoma (DLCL) with multidrug chemotherapy. The length of time to reach CR may be predictive of treatment outcome. However, defining CR by chest radiograph or computed tomography (CT) is often difficult since residual abnormalities do not always indicate residual disease. We have prospectively evaluated the ability of gallium-67 citrate (Ga-67) imaging to define residual disease and predict outcome in 37 consecutive patients with DLCL. Patients received 296 to 370 megabecquerels (MBq) Ga-67 and were imaged prior to, following cycles 4 to 6, and at completion of intensive chemotherapy. Ga-67 scan results were correlated with radiographic studies. Seventeen of 37 patients (46%) showed persistent, abnormal Ga-67 uptake halfway through chemotherapy. Of these, four were in CR, 11 were in partial remission (PR), and two showed no change in tumor size. At follow-up, 10 (59%) have died (three who were scored as CR and seven who were in PR halfway through therapy), two are alive with active tumor, one relapsed and survives following bone marrow transplant, and four (three in PR and one in CR at the therapeutic halfway point) are without disease at a median of 28 months from presentation. Of the 20 patients who were Ga-67-negative halfway through therapy, 11 were in CR and nine were in PR. Five of 20 patients (25%) have died. Three, in radiographic CR died at 11, 26, and 28 months, and two in radiographic PR died at 15 and 17 months. One patient is alive with active tumor, and 14 patients (70%) are alive without disease at a median of 34 months from presentation. Ga-67 imaging proved to be an excellent indicator of residual viable tumor; a positive scan halfway through therapy predicted for a poor outcome and may well justify a change in treatment.

Is mammography painful? A multicenter patient survey.

Anecdotal reports of pain experienced during mammography have been a source of anxiety and concern for some women considering screening. To determine what asymptomatic women actually experience during mammography, a survey of 1847 women was performed at seven breast-imaging centers. Women recorded their experience on a six-point scale ranging from no discomfort to severe pain. Eighty-eight percent of the women experienced no discomfort (49%) or mild discomfort (39%). Only 9% experienced moderate discomfort; 1%, severe discomfort; and 1%, moderate pain. No woman had pain so severe that it would make her reconsider having a mammogram again. The degree of discomfort was slightly greater in women who complained of breast tenderness within three days prior to the mammogram but was not strongly related to age, menstrual status, or week of the menstrual cycle. We conclude that in a vast majority of women mammography causes no or mild physical discomfort and that actual pain is an uncommon occurrence.

The m-BACOD combination chemotherapy regimen in the treatment of diffuse large cell lymphoma.

The m-BACOD regimen attempted to lower the dose of methotrexate in the M-BACOD (methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, dexamethasone) program. Between July 1981 and January 1985, 87 previously untreated or minimally treated patients with diffuse large cell lymphoma were treated with the m-BACOD regimen (methotrexate 200 mg/m2 on days 8 and 15, bleomycin 4.0 mg/m2 on day 1, doxorubicin 45 mg/m2 on day 1, cyclophosphamide 600 mg/m2 on day 1, vincristine 1.0 mg/m2 on day 1, and dexamethasone 6 mg/m2 on days 1 to 5; leucovorin was given 24 hours after methotrexate at 10 mg/m2 every six hours for eight doses orally). Of 86 evaluable patients, 59 (68.5%) had a complete remission (CR). Partial response was seen in 21 patients with six still surviving (5 to over 15 months). Of the seven patients who had no change, all have died. The median duration of follow-up for the entire series was 30 months (range, 2 to 61). Relapse from CR occurred in 15 of 59 (25%). Currently, 56 of 87 patients (64%) survive; all but 12 are in their first remission. Overall survival was 84% for those achieving an apparent CR. The major toxic effect of the m-BACOD regimen was myelosuppression with severe leukopenia and fever, which required hospitalization for about 33% of patients. Mucositis occurred in 39 patients; 19 had severe mucositis. No significant difference in overall survival was seen between the high-dose methotrexate M-BACOD and the low-dose m-BACOD regimens.

A phase I-II trial of cisplatin, hyperthermia and radiation in patients with locally advanced malignancies.

A Phase I-II trial testing the addition of systemic cisplatin (CDDP) to local hyperthermia and radiation was conducted to determine the dose of cisplatin that is tolerable once weekly for 6 weeks and to estimate the therapeutic potential of this trimodality combination in patients with locally advanced malignancies. Cisplatin at 20 mg/m2 (4 patients), 30 mg/m2 (8 patients), and 40 mg/m2 (12 patients) was given rapidly (over 5-10 min) i.v. after prehydration with 1 liter of normal saline. After approximately two-thirds of the cisplatin dose had been delivered, microwave hyperthermia was begun and continued for 60 min; the target minimum tumor temperature was 43 degrees C. Following hyperthermia, a 400 cGy fraction of radiation was delivered to the tumor. On other days during the treatment weeks, additional 200 cGy fractions were given to total doses of 6,000-6600 cGy in patients with full radiation tolerance or 2400-3600 cGy in patients with limited radiation tolerance. The 24 patients in this trial had a median age of 57 years and the predominant sites/tumor types were head and neck/squamous cell carcinoma (9) and chest wall/breast adenocarcinoma (9). Seventeen of the 24 treated tumors (70%) had previously been irradiated. Eighteen patients (75%) had received prior chemotherapy and nine patients (38%) had previously been treated with cisplatin. Bone marrow suppression was dose limiting in patients heavily pretreated with chemotherapy and chest wall radiation. No significant toxicities were observed at the 20 and 30 mg/m2 dose levels, but 5 of the 12 patients (42%) treated at 40 mg/m2 required modification of the cisplatin dose because of blood count suppression in four patients and mild renal dysfunction in one patient. Each of the patients with bone marrow suppression, however, had been heavily pretreated except for one patient with thrombocytopenia due to hypersplenism. Nausea and vomiting were mild with use of a standard, multiagent antiemetic regimen. Twelve patients (50%) attained a complete regression (CR) and 12 patients (50%) a partial regression (PR). Complete regression appeared to correlate with small tumor volumes (115 cc for CR versus 199 cc for PR patients) and higher tumor temperatures (4.6 average minimum equivalent minutes at 43 degrees C in CR versus 2.0 min in PR patients). Local toxicities included second degree burns in 12 patients (50%) and third degree burns in 6 (25%), but all burns healed in 4-12 weeks without surgical intervention.(ABSTRACT TRUNCATED AT 400 WORDS)

Gallium imaging in metastatic and recurrent soft-tissue sarcoma.

Fifty-six patients with metastatic or recurrent soft-tissue sarcoma were evaluated by 67Ga-citrate imaging. Prior to entry on the therapy protocol, 52/56 (93%) patients had true-positive 67Ga studies. Two of four patients with liposarcoma, one of twelve with leiomyosarcoma and one with an epithelioid sarcoma had false-negative studies; 89/105 disease sites (85%) were 67Ga positive, including 100% of pleural lesions, 94% in bone, 88% in the abdomen, 85% in soft tissue, 78% in lung parenchyma and 56% of liver metastases. There was significant association between 67Ga avidity and tumor grade with the exception of mesothelioma. No relationship was seen between 67Ga avidity and tumor cell type, disease site or lesion size. Following therapy, 67Ga correctly identified 11/12 sites of active disease in 8/9 patients. Mean pre- and post-therapy 67Ga avidity scores did not differ significantly. Gallium-67 appears to have an important role in the evaluation of patients presenting with either primary or metastatic soft-tissue sarcoma.

Association between number and sites of new bone scan abnormalities and presence of skeletal metastases in patients with breast cancer.

Review of 1,441 bone scans performed on 242 breast cancer patients without known skeletal metastases identified 239 scans with new abnormalities. Findings on 54 of these 239 scans (23%) represented bone metastases. The proportion of scans reflecting metastases, grouped by the number of new abnormalities, was: (1) 20/182 (11%); (2) 9/26 (35%); (3) 4/9 (45%); (4) 1/2 (50%); greater than or equal to 5-20/20 (100%). When metastatic disease presented as a bone scan with 1-4 new abnormalities, the spine was the most common site of involvement (18 of 34 (53%)), followed by the skull (5/34; 15%), extremities and sternum (each 4/34; 12%). Rib lesions were the most common new findings on scans with less than 5 new abnormalities (seen on 76 of 219 scans (35%)) but only infrequently represented metastases (n = 2). Considering as indicative of malignancy only, those bone scans which demonstrated either (a) greater than or equal to 5 new abnormalities, (b) initial radiographic correlation suggestive of metastases, or (c) thoracic spine lesions with normal correlative radiographs, the presence of skeletal metastatic disease could be predicted with a sensitivity of 0.80 and a specificity of 0.94.

The treated thorax.

Significant progress has been made in the treatment of Hodgkin's disease and non-Hodgkin's lymphoma. Responses to treatment may vary. Complications often occur. This article reviews the radiographic and clinical aspects of how the thorax responds to treatment.

Post breast conservation therapy imaging and local recurrence.

Breast conservation therapy, which includes lumpectomy usually followed by breast irradiation, is an effective and commonly used therapy for women with resectable breast cancers. Although the rate of local recurrence has decreased over the years, these women continue to be at risk with an overall incidence of local recurrence of 1-2% per year for 10 years. The incidence of local recurrence varies according to age and receptor status. Studies have shown that early detection of in breast recurrence or second primaries reduces mortality. Mammography and clinical breast examination can be effective in the detection of recurrence. The efficacy of mammography, recommended intervals for screening and the various mammographic appearances of recurrence are addressed in this paper. Other breast imaging modalities including breast ultrasound and breast magnetic resonance imaging have less of a defined role. There is little data on ultrasound in this setting and the available data on magnetic resonance imaging after breast conservation therapy is evolving and will be presented. Finally, benign disease mimicking tumor recurrence and commonly missed appearance of tumor recurrence are discussed.

The efficacy of routine whole lung tomography in germ cell tumors.

A prospective analysis was undertaken to evaluate the efficacy of performing routine whole lung tomography in addition to conventional chest radiography in the initial staging and subsequent management of 120 patients with seminomatous and nonseminomatous germ cell tumors. Two hundred fifty whole lung tomographs were performed on these patients. At presentation, only one patient (0.8%) had positive tomography with simultaneously normal posteroanterior and lateral chest films. On follow-up tomographic examinations, three patients had metastases when chest roentgenographs were normal. In only one patient was therapy altered by tomographic findings. The results indicate that routine whole lung tomography is not useful or cost-effective in the initial staging and subsequent management of patients with germ cell tumors.

Residual abdominal masses after chemotherapy for nonseminomatous testicular cancer: correlation of CT and histology.

Computed tomographic (CT) characteristics of 45 residual masses in 30 patients with disseminated nonseminomatous testicular cancer treated with chemotherapy were correlated with histologic findings at surgery. Thirty-one masses were studied serially on pre- and postchemotherapy scans. At the time of tumor-reductive surgery, all patients had normal serum tumor markers (alpha-fetoprotein and human chorionic gonadotropin). Residual malignancy was found in 27% of patients, teratoma in 33%, and fibrosis or necrosis in 40%. The CT appearance of the masses--size, qualitative density, and change noted during the course of treatment--was insufficient to exclude the presence of residual malignancy or teratoma. An enlarging mass of psoas density occurred only once in this series; it contained malignancy. Other CT characteristics of residual masses had no greater than 50% correlation with the presence of malignancy. Histologic evaluation of residual masses remains necessary to guide further patient management.

Peri- and paracardial involvement in lymphoma: a radiographic study of 11 cases.

Eleven patients with pericardiac and paracardiac lymphomatous involvement were studied. Computed tomography (CT) of the chest was compared to plain chest films for its ability to define the sites and extent of involvement in the paracardiac area. Nine of the 11 patients had abnormalities on chest radiography, which included abnormal contours in the fat pad areas and along the heart border, or an enlarged cardiac silhouette. Two patients had normal cardiac silhouettes; however, CT showed definite abnormalities. CT differentiated adenopathy from fat pads in two patients and pericardial effusion from cardiomegaly or paracardiac adenopathy in two patients. The exact location and extent of the paracardiac adenopathy initially seen on chest film was defined by CT. Careful analysis of the peri- and paracardiac areas by plain films and CT is essential to the diagnosis and the proper management of patients with Hodgkin and non-Hodgkin lymphoma.

Mammographic detection of recurrent cancer in the irradiated breast.

Recurrence of cancer in the irradiated breast is an uncommon but potentially curable problem. Posttreatment mammograms were studied in 45 patients who had biopsies of an irradiated breast for suspected local recurrence to evaluate the usefulness of mammography in detecting such recurrences. Of 23 biopsy-proven recurrences, eight (35%) were detected by mammography only, nine (39%) were detected by physical examination only, and six (26%) were detected by both. Mammographic findings in recurrent malignancy included microcalcifications in six, microcalcifications associated with a mass in four, soft-tissue masses in three, and inflammatory changes in one. The results show that mammographic follow-up is complementary to physical examination in the detection of local recurrence in women who have undergone radiation therapy for early breast cancer.

CT evaluation of advanced seminoma treated with chemotherapy.

The serial CT characteristics of nodal metastases from pure seminoma treated with chemotherapy were evaluated in 18 patients. Fifty percent of masses at presentation contained areas of low attenuation; none had calcification. After chemotherapy, masses completely resolved in four patients, partially resolved in 12 patients, and remained unchanged in one patient. The remaining patient developed progressive liver metastases during therapy and died. Pathologic evaluation of residual masses in four patients demonstrated only fibrosis. Residual masses in nine other patients demonstrated further partial resolution or remained stable over the following year; two developed calcification. These patients exhibited no clinical evidence of disease for a median follow-up of 22 or more months. Persistent but stable or resolving masses are common after chemotherapy for advanced seminoma. Unlike their nonseminomatous counterparts, they most often represent fibrosis in patients with no other clinical evidence of disease and do not warrant surgical excision.

Planning mantle radiation therapy in patients with Hodgkin disease: role of gallium-67 scintigraphy.

Detection of all sites of lymphoma is imperative for accurate planning of radiation therapy. In patients with Hodgkin disease, mantle radiation is used to treat the thoracic lymph nodes; in those with early-stage or nonbulky disease, mantle and paraaortic radiation may be the only treatment given. CT scanning of the chest adds important information to that obtained from chest radiographs. Gallium-67 scintigraphy has also been used to provide additional information on sites of active tumor. To determine the usefulness of 67Ga-citrate scintigraphy in planning the portals for radiation therapy, we analyzed the radiation treatment plans in 26 consecutive patients with Hodgkin disease; in all 26 patients, the disease had been staged by chest radiographs, chest CT scans, and gallium-67 images. Gallium-67 imaging alone provided unique information that affected the treatment plans in three patients (12%). The combined results of gallium-67 imaging and CT scans influenced the planning of radiation therapy in eight patients (31%). Gallium-67 imaging was found to be an important adjunctive study for optimal planning of radiation therapy in patients with Hodgkin disease.

Detection of retroperitoneal metastases in early-stage nonseminomatous testicular cancer: analysis of different CT criteria.

To determine the predictive values of using different sizes on CT as criteria for the detection of retroperitoneal lymph-node metastases in patients with early-stage (nodes 5 cm or less in diameter) primary nonseminomatous testicular cancer, we performed a retrospective analysis of 51 patients. Measurements of lymph-node transaxial diameters on CT were correlated with histologic findings at lymph-node dissection or with response to initial chemotherapy. All patients had normal serum markers (alpha-fetoprotein, human chorionic gonadotropin) after orchiectomy. The frequency of lymph-node metastases in this population was 51%. When a CT criterion of 5 mm was used, the negative predictive value was 79%; the positive predictive value, 62%; the specificity, 44%; and the sensitivity, 88%. With a criterion of 15 mm, the negative predictive value was 63%; the positive predictive value, 71%; the specificity, 76%; and the sensitivity, 58%. Metastases in retroperitoneal lymph nodes that appeared within normal limits (i.e., had normal transaxial diameters) on CT were the limiting factor in the ability of CT to exclude the presence of metastases. We conclude that using smaller sizes on CT scans as the criteria for detection of lymph-node metastases cannot replace dissection of nodes in patients who have normal-sized nodes but may be helpful in identifying a subgroup of patients who are at lower risk of harboring metastases when treatment by orchiectomy alone is considered.

Drug-related pulmonary toxicity in non-Hodgkin's lymphoma. Comparative results with three different treatment regimens.

Pulmonary toxicity may complicate the treatment of non-Hodgkin's lymphoma (NHL). The possible drug-related cause of pulmonary toxicity was investigated retrospectively in 207 NHL patients treated between 1981 and 1988 with three regimens containing cyclophosphamide with and without methotrexate or bleomycin: methotrexate, calcium, leucovorin, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone (m-BACOD) (n = 134); methotrexate, calcium, leucovorin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone (m-ACOD) (n = 43); or cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) (n = 30) chemotherapy. These regimens contained the same drugs and were administered in the same schedule; the regimens differed primarily in the addition of bleomycin or methotrexate. Pulmonary toxicity occurred in 24 of 134 (18%) m-BACOD-treated and in six of 43 (14%) m-ACOD-treated patients (P = 0.65). Chest radiography revealed diffuse pulmonary infiltrates in 16 (67%) and six (100%) of the m-BACOD-treated and m-ACOD-treated patients with pulmonary toxicity, respectively. None of the CHOP-treated patients had pulmonary toxicity. The clinical features of pulmonary toxicity and the amount of chemotherapy administered before it occurred did not differ in patients treated with m-BACOD or m-ACOD, although the toxicity tended to be more severe in the m-BACOD group. Open lung or transbronchial biopsies done in six (38%) of the m-BACOD-treated and three (50%) of the m-ACOD-treated patients with pulmonary infiltrates revealed nonspecific pneumonitis compatible with drug-related toxicity. In summary, these results showed that pulmonary toxicity during m-BACOD and m-ACOD therapy occurred with similar frequency and clinicopathologic features. This suggested that bleomycin was not responsible uniquely for the pulmonary toxicity in m-BACOD-treated patients. That pulmonary toxicity was not observed in patients treated with CHOP suggested that methotrexate may play an important role in the pathogenesis of the pulmonary toxicity.