Type I

PPB/DICER1 Registry Treatment Recommendations

PPB therapy choices are the decision of each institution. The PPB/DICER1 Registry presents surgery and chemotherapy guidelines.

The International PPB/DICER1 Registry is not a part of, nor funded by, any cooperative oncology group, although Children’s Oncology Group Rare Tumor Sub-Committee recognizes the Registry as a major collection of PPB cases.

The PPB/DICER1 Registry offers the following treatment recommendations for Type I PPB based on anecdotal Registry and literature information discussed below.

Surgery - Type I PPB

In many Type I cases, the indication for surgery is cystic lung disease and there is little pre-operative concern about a malignancy. The clues to a malignant process would be bilateral cystic lung disease*, an extensive multilocular cyst*, or any family history of lung cysts, cystic nephroma, or childhood cancer. See Constitutional Disease: Lung Cysts and More and Familial Disease and Dysplastic and Neoplastic Conditions in PPB Patients and their Families. (*Bilaterality rarely occurs also in benign cystic lung malformations.)

This study recommends thoracotomy for predominantly cystic lesions. However, because pre-operative evaluation of predominantly cystic lesions is unlikely to suggest malignancy, thorascopic resections may be undertaken.

Type I disease is entirely cystic and may be unilocular or multilocular, unifocal or multifocal, and unilateral or bilateral. Every attempt should be made to remove completely all cystic remnants, but the Registry has seen cases in which not all cysts in a Type I patient show the changes of Type I PPB. Therefore, the Registry understands that in children with widespread cystic lung changes, not all the cysts can or should be removed. Type I recurrences frequently progress to more serious Type II or III disease (see Prognosis for PPB).

The secured PPB/DICER1 RegistryInformation Portal provides physicians further details for treating Types I, II, and III PPB, including a copy of the Registry’s treatment protocol (offered at request) and consent forms.